text:
Talk:Chimpanzee

Wiki Education Foundation-supported course assignment
This article was the subject of a Wiki Education Foundation-supported course assignment, between 18 January 2021 and 8 May 2021. Further details are available on the course page. Student editor(s): Yisaginath.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 17:28, 16 January 2022 (UTC)

"In culture" section?
"Gio masks are crude and blockly and the people wear when teaching young people how not to behave." Uh, is "blockly" even a word? I assume the sentence should read "people wear them when teaching..." Muzilon (talk) 10:55, 8 October 2019 (UTC)
 * Maybe replace "blockly" with broccoli. Broccoli certainly teaches young people how to behave! Randy Kryn (talk) 13:17, 8 October 2019 (UTC)

More relevant than that, I'd like sources for "Chimpanzees are rarely represented in African culture, as people regard them as too close to humans for comfort." Somewhat related to the subject of cultural knowledge, "Who Knows What About Gorillas? Indigenous Knowledge, Global Justice, and Human-Gorilla Relations", from the abstract, "Indigenous knowledge of gorillas is almost entirely absent from the global canon. The absence of African accounts reflects a history of colonial exclusion, inadequate opportunity, and epistemic injustice." Already provides a more satisfying "explanation." Extremophile (talk) 20:08, 10 February 2022 (UTC)

Protection for the Chimpanzee page
Lately, there has been a lot of vandals/trolls who have vandalized the page. So maybe this page needs to be protected so that only auto-confirmed users could edit the page, reducing the chance of vandalism. DinosaursRoar (talk) 19:32, 15 September 2020 (UTC)
 * I agree. I think requiring auto-confirmed users is a good idea in light of the persistent vandalism to the article. --MadScientistX11 (talk) 01:49, 17 September 2020 (UTC)
 * DinosaursRoar Some mobile user keeps making changes. As far as I can tell they are just deleting large sections of text and then putting them back. I haven't reverted them because I'm not completely sure, perhaps they are making some minor formatting improvements that I'm not seeing but I have a feeling they are either just playing around or trying to up their edit count. What do you think? --MadScientistX11 (talk) 17:09, 17 September 2020 (UTC)
 * there’s been a lot of vandalism lately, so it should be protected. 2603:9000:E706:8872:4D81:BE1F:D327:8D31 (talk) 22:27, 6 June 2022 (UTC)

Space chimp
Should the "Use in research" subsection of this article include images of both Ham and Eos, the chimps who have been sent into space? Or would one image of one of them suffice? LittleJerry (talk) 00:55, 10 June 2021 (UTC)

You should have "checked the other recent edits" because I added information on both Ham and Enos in the section so I could remove the Enos image due to sandwiching. LittleJerry (talk) 12:59, 9 June 2021 (UTC)
 * Hi (moved from my talk page). Then let's work around that, maybe move the image higher on the page near the lead, although the sandwiching is quite minimal and doesn't seem a problem. Enos is easily and arguably the most important chimpanzee regarding human-chimp interaction. He is the only chimp, and third great ape, to orbit the Earth (should have been given a ticker-tape and banana parade), a historic feat. Most readers will not read every word of text, one reason why images are so important for those who don't, a "picture book" reader. That type of reader should be taken into account on every Wikipedia page, which is why captions contain links even if the text has the same link. Glad you expanded Enos and Ham on the page text for text readers, nice work. Randy Kryn (talk) 13:25, 9 June 2021 (UTC)
 * we can't have two space chimp images, especially since the subject is only a tiny part of the subsection. I prefer the Ham image since it is better quality, shows him in a capsule and surrounded by fellow astronauts. The images tells us a lot more than a b+w closeup of a chimp in a suit. LittleJerry (talk) 18:16, 9 June 2021 (UTC)
 * Why not? These two chimpanzees are likely the two most historically important chimpanzees in human history. Ham did a suborbit as the first great ape to reach space, and then Enos (the close-up of a chimp in a suit, but not just any chimp...) topped-that-tall-tree by becoming the third great ape, after Russian cosmonauts Yuri Gagarin and Gherman Titov, to orbit the Earth. Including both photos seems fine and encyclopedic appropriate, considering these feats. Randy Kryn (talk) 21:48, 9 June 2021 (UTC)
 * Their are several famous chimps including Nim Chimpsky, Bubbles and Oliver and not all of them deserve an image on the page. The image of Enos is also of poor quality and tells us nothing. LittleJerry (talk) 21:57, 9 June 2021 (UTC)
 * Ham and Enos are in a class by themselves historically, and are remembered together. Maybe other editors will drop in, but consensus may need a full RfC. Please stop reverts, the images have been on the page for awhile. I really don't see the problem. You asked for a reference for Enos flight, and I've added that. Randy Kryn (talk) 00:39, 10 June 2021 (UTC)
 * People are more familiar with Bubbles than Enos. The problem is that the image sandwiches the text, is redundant and tells the readers nothing. The subsection itself has only three sentences on space chimps and we have two images given to them. LittleJerry (talk) 00:54, 10 June 2021 (UTC)
 * Yes, Ham and Enos' importance to human culture, to chimpanzee-human collaboration, and to human use of chimpanzees for research and experimentation, which is what the section is about, should contain two or three more sentences. Images of these two space pioneers (the first Great Ape to enter space and the third to orbit the Earth following two Soviet flights) represents the literal height of that forced partnership. That such historical chimpanzees existed seems reason enough to allow one action and one portrait image (maybe they can be combined into one block-image, that would solve the sandwiching). As for the portrait of Enos, no context except in the caption, no space equipment readily visible, just a dignified close-to-heroic photograph of a caged historical figure within the section dedicated to describing his species and its relationship with other Great Apes who built, from the sand up, the means and methods. But yeah, maybe a double image with a single-caption would be a good collab solution and unsandwich the text. Randy Kryn (talk) 03:11, 10 June 2021 (UTC)
 * I previewed the double image (and shifted it right) and it pushes the Goodall station into "attacks". I really don't see that as necessary and not worth doing for a redundant and poor quality image. If the Rfc closes with no other users commenting, I think we should remove the Enos image. LittleJerry (talk) 20:15, 11 June 2021 (UTC)
 * Just saw that you did post this as an RfC, so gave a simple note to the primate and spaceflght WikiProjects. Everybody putting their heads and edits together should benefit this already interesting article. Randy Kryn (talk) 03:32, 10 June 2021 (UTC)
 * I vote for just Ham and linking Monkeys_and_apes_in_space somehow. --Neopeius (talk) 16:32, 10 June 2021 (UTC)
 * Link done. LittleJerry (talk) 20:17, 11 June 2021 (UTC)

 * Requesting comments from, , , and  who were very active in the January 2019 discussion on moving Common chimpanzee to Chimpanzee. LittleJerry (talk) 20:23, 11 June 2021 (UTC)
 * Perhaps create a collage image of chimps important to science? BD2412  T 21:15, 11 June 2021 (UTC)

 * The Enos image is low quality so could be reduced and put to the right of the Ham image so they get displayed as a single double image. The multiple image template that allows two images to be displayed with automatic resizing to the same height (see right). The total_width parameter can be adjusted to match the map above it in the article. The captions can be set for each image or a combined one added with footer, which seems best here. —  Jts1882 | talk 08:59, 12 June 2021 (UTC)
 * As suggested above, I would also use the image of Ham at the summary of chimps in space with links to the associated articles in the prose and caption. It's not rocket science! ha-ha-ha :| ~ cygnis insignis 12:05, 12 June 2021 (UTC)
 * pinging, , and . More users who were also involved in the January 2019 discussion. LittleJerry (talk) 13:21, 16 June 2021 (UTC)
 * When pinging participants of past discussions, especially when you did it in two batches, please ping all of them. Thanks. Adding, , , , , , , , , , , and . Randy Kryn (talk) 20:32, 23 June 2021 (UTC)
 * I was pinged. I had argued that “chimpanzee” includes the bonobo.
 * Today the question goes to providing images of the two space chimps. The images do not add to the understanding of the topic, so these images are unimportant, they serve only as illustration.  The two images do not complement each other, do not work well together.
 * I suggest that neither should be included. They do not add information, and do not improve the presentation of an article that already has many images.  Two images is definitely over balance to the single sentence that covers the space chimps   SmokeyJoe (talk) 13:32, 16 June 2021 (UTC)
 * (outdenting) I agree that only one or no images of the space chimpanzees need to be in the article. The subsection is not that big and the two images don't add much of value. --SilverTiger12
 * The first primate in space (worth repeating, first primate in space) and the third (after two humans) to orbit the Earth, are historically significant individuals. They are in the section relating to research, so fit the topic perfectly. In any case, will use the double photo to play with a caption a bit later. Randy Kryn (talk) 19:41, 23 June 2021 (UTC)
 * That’s amazing information about the chimp, and is best covered at the chimp’s article. Both chimps have articles. But this research, what did it tell us about chimpanzees? SmokeyJoe (talk) 07:52, 26 June 2021 (UTC)
 * A correction: the monkey Albert II became the first primate in space in 1949 (he doesn't yet have a Wikipedia page) while Ham was the first great ape in space. What did Ham tell us? That human's closest relatives could survive a brief time in space without any unforeseen circumstances, so it seemed okay to send Alan Shepard, America's second great ape in space. As a side benefit, Ham and Enos entered the human history books and record books when writing about their species as research subjects, which is the section of this article being discussed. Randy Kryn (talk) 12:37, 26 June 2021 (UTC)
 * Are we missing the article on Monkeys in space? https://www.space.com/19505-space-monkeys-chimps-history.html SmokeyJoe (talk) 12:53, 26 June 2021 (UTC)
 * It is there. Not cheering reading. SmokeyJoe (talk) 12:55, 26 June 2021 (UTC)
 * Yes, what's more fun than multiple crashing steel barrels of monkeys. Maybe time for the Wikipedia page for Albert II, thanks, a good source. Randy Kryn (talk) 13:10, 26 June 2021 (UTC)
 * ✅ as a stub, Albert II (monkey). Thanks for inspiration, and please dive in (but not too close to the ground) to monkey around with it. Randy Kryn (talk) 14:04, 26 June 2021 (UTC)

Wrote up a caption which seems to get everything in while keeping it brief. Since the section being discussed is the 'chimpanzees as research subjects' section the caption accents this status while giving the individual apes their due historical respect. Personally I'd place the portrait image of Enos near the top of the page. Should have been given a ticker-tape parade. Randy Kryn (talk) 03:21, 26 June 2021 (UTC)
 * p.s. put together a second option using a close-up cropped from Ham's photo. Will support this one for the page, the two portrait images of these historical figures go well together. Randy Kryn (talk) 03:42, 26 June 2021 (UTC)
 * I still would prefer the single image of Ham. I really don't understand Randy's insistence on keeping the Enos image. Enos may be important but that does not mean we need a poor quality picture of the head and shoulders of a chimp in a suit doing nothing remarkable. At least Ham's image has him in a capsule surrounded by NASA people. LittleJerry (talk) 20:04, 26 June 2021 (UTC)

 * One image, Ham. Two images is undue weight to represent such a tiny bit of article text, given that the article is already so large and heavily illustrated. In fact the article is so heavily illustrated that the images are getting pushed away from the relevant text, making it difficult to connect images with their related text. The Ham image has much more informative context of the two (sitting in the special capsule-seat), and I don't see the Enos image adding much unique value. Alsee (talk) 17:03, 27 June 2021 (UTC)
 * One image, Ham, not zoomed in. One is enough, the other is crap quality, one is appropriate given the importance of the "space chimps" in the human context, and not zoomed in because this is not an article on Ham, but about chimps, with a section on use in research, and the humans in the picture, along with the equipment, illustrate the context better.  — SMcCandlish ☏ ¢ 😼  06:21, 29 June 2021 (UTC)

 * 20 days and we have 3 in favor of keeping Enos and 7 against. LittleJerry (talk) 13:37, 29 June 2021 (UTC)
 * Aye, alas poor Enos, we knew you well. Randy Kryn (talk) 13:51, 29 June 2021 (UTC)

Chimpanzee for 'Chimp'
After changing the slang word 'chimp' to the proper name 'chimpanzee' Little Jerry reverted dozens of instances on this page in good faith. The proper name for chimpanzee is chimpanzee, not Chimp. Although chimp is listed as an alternate name in the lead, many pages have slang terms listed as alternate names but they aren't used as descriptors in the text of articles. The species name is chimpanzee, the title is Chimpanzee, and aside from those obvious points for using the full species name, "chimpanzee" gives the animals the proper respect as a cousin animal. Randy Kryn (talk) 22:43, 27 September 2021 (UTC)
 * Chimp is not merely a slang term, it is also used by scientists in reliable books as well because it is a short hand. The rhinoceros and hippopotamus articles alternative between those names and "rhino" and "hippo" respectively. Likewise, other animal article use alternative names like killer whale/orca. LittleJerry (talk) 00:12, 28 September 2021 (UTC)
 * Prefer "chimpanzee" over "chimp" unless quoting or paraphrasing a source. Chimp is a mild colloquialism, and "chimpanzee" is better suited to the tone of Wikipedia.  The Latin scientific name would going too technical.  Any argument to change to prefer "chimp" should be based on prevailing source usage in quality sources, starting with the current best sources for the article. SmokeyJoe (talk) 04:13, 28 September 2021 (UTC)
 * Requesting comments from, , , . , , . LittleJerry (talk) 00:37, 28 September 2021 (UTC)
 * Will add one,, who has edited the page regarding this discussion topic. Randy Kryn (talk) 01:41, 28 September 2021 (UTC)
 * I feel that I would generally prefer the use of "Chimpanzee" in an encyclopedia article. BD2412  T 00:53, 28 September 2021 (UTC)
 * Correct, per the Pan (genus) page which states that "the colloquialism 'chimp' was most likely coined some time in the late 1870s." Our article on this topic opens "Colloquialism is the linguistic style used for casual communication. It is the most common functional style of speech, the idiom normally employed in conversation and other informal contexts." and states that "Colloquialism or general parlance is distinct from formal speech or formal writing." An encyclopedia builds itself with formal writing. Film titles have often used the word "Chimp", for example, but that use reflects casual use, not the formal writing style used on Wikipedia. Randy Kryn (talk) 01:31, 28 September 2021 (UTC)
 * If you want it all be be formal, then why not go further and use the scientific name instead? Wikipedia uses causal names all the time, like "rhino", "hippo" and "seal" (pinniped). Wikipedia is not suppose to be a super technical website but appeals to general readers. "Chimp" is just as commonly used for the species as "chimpanzee". It is not just a slang term. LittleJerry (talk) 01:45, 28 September 2021 (UTC)
 * Because most scientific terms confuse or lose readers, and are not understandable to the vast majority of English readers. Please read Colloquialism, which defines formal and informal language. Didn't think of rhino or hippo, which could be discussed on their talk pages. Randy Kryn (talk) 01:48, 28 September 2021 (UTC)
 * And even as this discussion is going on, LittleJerry is reverting edits on other chimpanzee pages and not waiting until this discussion is completed., I hope you will revert your edits if this discussion agrees on formal language. Thanks. Randy Kryn (talk) 01:51, 28 September 2021 (UTC)
 * Rhinoceros, hippopotamus and chimpanzee are all long complicated words that get tiresome when repeated over and over again, hence why the short-hands exist. LittleJerry (talk) 01:54, 28 September 2021 (UTC)
 * And FWI YOU'RE the one making the bold changes to the different articles so YOU'RE the one who has to wait for consensus. LittleJerry (talk) 01:57, 28 September 2021 (UTC)
 * Indoor voice please (or not). All I asked was that you consider reverting your reverts if this discussion, which with all the pings could either end quickly or go on for awhile, ends. A good point for the rhino and hippo, but chimpanzee seems uncomplicated and familiar as a species name. Rhino and hippo could be addressed at their talk pages, although the more I read your reply the more familiar and uncomplicated the words rhinoceros and hippopotamus as formal species names become. Randy Kryn (talk) 02:01, 28 September 2021 (UTC)
 * I agree with that chimpanzee is more appropriate for an encyclopaedia article. Similarly for rhinoceros and hippopotamus (although not seal). To me, chimp seems even more informal than rhino or hippo, perhaps because its sometimes used a pejorative for people. I'll add that I reply because I was pinged rather than because I feel strongly about it. Looking at the article, chimpanzee and chimp are perhaps used excessively, often several times in a sentence. Changes to use pronouns or alternative words might improve the style. —  Jts1882 | talk 08:31, 28 September 2021 (UTC)
 * "Chimp" is an informal term, and has no place in a professional encyclopedia per WP:Encyclopedic tone. I have reverted, as LittleJerry seems to be in a minority of 1 in thinking it's appropriate. — Amakuru (talk) 08:38, 28 September 2021 (UTC)

 * My vote is for chimpanzee over chimp. Much better suited for the article, I don't hear chimp being used all that much in the UK. Cheers, Jack (talk) 16:51, 28 September 2021 (UTC)
 * Yes, use chimpanzee not the informal abbreviation chimp. MOS:ABBR, MOS:TONE.  PS: Same goes for rhino and hippo.  Two other articles with the same problem doesn't make a norm, but a bigger problem to clean up.  — SMcCandlish ☏ ¢ 😼  00:19, 29 September 2021 (UTC)
 * , hi. Okay to say this seems decided, for at least 'chimp'? Thanks. We've had some good tussles (the space chimp discussion above this one) and during both of them I've taken a peep at some of your extensive work on animal pages. Regarding animals you are a Wikipedia natural treasure, and as an animal guy since childhood, thank you. Your work makes me once again wonder why there are relatively so few past and active professional editors for a major topic area (primatologists, zoo and wildlife sanctuary personnel, animal rights activists, professional researchers, writers, and editors on the topic, etc.). Almost like another mid-2000s Wikipedia Renaissance is waiting to happen when thousands of older or newly-minted professionals in all fields awaken to the growing-by-the-second importance and potential of this encyclopedia. Randy Kryn (talk) 14:17, 30 September 2021 (UTC)
 * Thanks buddy. I appreciate it. LittleJerry (talk) 21:09, 30 September 2021 (UTC)
 * Apologies, invited but forgot to vote. I have received mail and fine notices on similar issues before, but wish to issue a claim of diminished responsibility and assure pinger that no offence was intended by that unintentional oversight. ~ cygnis insignis 18:12, 18 January 2022 (UTC)

Chimpanzee page neeeds Protection
There has been so much vandalism lately on this article, so this is why the Chimpanzee page needs protection (possibly indefinite) against vandals. Therizinosaurus2 (talk) 05:36, 15 January 2022 (UTC)
 * Personally I don't think that three incidents of vandalism in the last week, all from the same IP, warrants page protection, but if you want to request this, you should post the request at WP:RFPP. CodeTalker (talk) 06:01, 15 January 2022 (UTC)
 * The proper place to make that request is Requests for page protection. Peaceray (talk) 06:02, 15 January 2022 (UTC)
 * I submitted a request for protection. There has been so much vandalism, it gets hard to find the last good page. Also, at least one vandalism included a racist slur which IMO increased the justification for protection. There was an Admin backlog tag on the protection page so it may be a while before an admin has time. In the meantime thanks to everyone who keeps restoring the pages. I’ve been so busy lately I only have time to check once in a while. One last point, IMO it is always a good idea to add a vandalism tag to any user’s talk page after reverting. --MadScientistX11 (talk) 14:36, 9 February 2022 (UTC)

About the Image
It's just that how come this image is used for speciesbox anyway? Esagurton (talk) 14:57, 18 January 2022 (UTC)
 * Someone thought it a good idea? I favour weighting inclusion of an image, when it is not directly supported in the adjacent prose, by means that are determined externally (verifiably notable). ~ cygnis insignis 18:01, 18 January 2022 (UTC)
 * Perhaps we could come to a consensus on a lead image? I could round up some candidates. I personally prefer the current one, it does have vegetation covering parts of it but it shows the chimp in its natural habitat, in a tree among its favorite food. The individual is also youngish looking which is probably what people picture when they think "chimp" as opposed to an older alpha male or lactating female. ? LittleJerry (talk) 20:09, 19 January 2022 (UTC)
 * Missed your ping, sorry. Yes, seems a good lead image. "In a tree among its favorite food", has a nice feel. Randy Kryn (talk) 04:26, 11 February 2022 (UTC)
 * With some hesitancy, that is a clear shot although partly obscured. File:Pan troglodytes (male).jpg shows it walking, there are a couple with infants being cradled, I feel thses are the more informative of the species. ~ cygnis insignis 05:07, 11 February 2022 (UTC)
 * Good walking image, should be used somewhere (unused so far). Randy Kryn (talk) 10:44, 11 February 2022 (UTC)
 * Even a crop to the image at right to frame the subject, but I picked that one because it is not an arboreal species. ~ cygnis insignis 14:35, 11 February 2022 (UTC)

Chimpanzee
I notice a CN tag was reverted at this section, because it is stated in the ref at the end "Werness, H. B. (2007). The Continuum Encyclopedia of Animal Symbolism in World Art." I get a snippet view that suggests something like that, but it is a quirky statement in tertiary source. The section could be improved, if some agreement on what "in culture" is possible. ~ cygnis insignis 01:41, 11 February 2022 (UTC)
 * See here Allen Roberts writes that Africans living in the same environment as chimpanzees rarely represent them, perhaps because, as the Tabwa say, they are best ignored and avoided, "as too close for comfort". I originally add the quotations around "to close for comfort" but they were removed. LittleJerry (talk) 18:11, 12 February 2022 (UTC)
 * I saw that it was supported by the ref, and searched the snippet view on this name to get a feel for the work. I suppose it requires finding other refs to refine the section if I find it odd, perhaps change the name, so will come back to it when some turn up. ~ cygnis insignis 18:38, 12 February 2022 (UTC)

Edit reversion?
I made the spelling of "behavior" and "behaviour" consistent, and my edits were reverted. Is consistent spelling not more professional? Cassie Schebel (talk) 16:16, 9 March 2022 (UTC)

Apologies, the issue has now been resolved. Cassie Schebel (talk) 16:22, 9 March 2022 (UTC)

Semi-protected edit request on 6 January 2023
The references to the phrase "Eidetic Memory" under the Cognition section should be removed as there is no reference to it in the source provided, and it would indicate an unproven phenomenon 95.44.126.98 (talk) 21:45, 6 January 2023 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. UtherSRG (talk) 01:59, 7 January 2023 (UTC)
 * I think he meant to use fv. SmokeyJoe (talk) 02:26, 7 January 2023 (UTC)
 * I haven’t checked the source (Ref 115, https://www.sciencedirect.com/science/article/abs/pii/S0959438809000269?via%3Dihub), but the same information about chimpanzee photographic (like humans have) memory is in https://doi.org/10.1016/j.cub.2007.10.027 SmokeyJoe (talk) 02:25, 7 January 2023 (UTC)

Longest lifespan
This article says "The oldest known male captive chimpanzee to have been documented lived to 66 years, and the oldest female, Little Mama, was over 70 years old." But apparently J. Fred Muggs is 71 years old. Either that chimp is actually dead or the record lifespan needs to be changed. 2607:FB91:188:9A00:AE:A558:31B7:9023 (talk) 00:00, 24 July 2023 (UTC)

 * If you have a reliable and independent source that says Muggs is alive or not, we can use that to update. The current reference was from 2018, when he was 65. - UtherSRG (talk) 15:36, 24 July 2023 (UTC)

Moved
A vandal once moved this page (and its talk) to an inappropriate title. Per WP:DENY, the moved main page is hidden in the move log, but it’s still there in the talk page move log. Could someone please fix it? 174.211.175.132 (talk) 14:13, 12 December 2023 (UTC)
 * ✅. Thanks. — Amakuru (talk) 16:24, 12 December 2023 (UTC)

Semi-protected edit request on 27 December 2023
in section Characteristics, third paragraph is currently: "Chimpanzee skin that is covered with body hair is white, while exposed areas vary with it being white passing with age into a dark muddy colour in eastern chimpanzees, freckled on white which with age becomes muddy in colour and heavily mottled central chimpanzees; and black forming butterfly-shaped white mask that with age darkenings in western chimpanzees."

extremely strange phrasing on this sentence, i would change it to:

"Chimpanzee skin that is covered with body hair is white, while exposed areas vary: white which ages into a dark muddy colour in eastern chimpanzees, freckled on white which ages to a heavily mottled muddy colour in central chimpanzees, and black with a butterfly-shaped white mask that darkens with age in western chimpanzees." Spatulatrix (talk) 22:32, 27 December 2023 (UTC)

✅ Rehsarb (talk) 22:41, 27 December 2023 (UTC)

Semi-protected edit request on 4 January 2024
Please change the confusing and misleading "physical strength 1.5 times greater than humans" to "muscles 50% stronger per weight than those of humans" ("mass-specific"), which is what the linked reference actually supports; particularly clear in its discussion appendix. WJBC-NG (talk) 23:26, 4 January 2024 (UTC)
 * ✅ UtherSRG (talk) 00:42, 5 January 2024 (UTC)
 * What? It also states "available data suggests that chimpanzee mass-specific muscular performance is a more modest 1.5 times greater than humans on average". LittleJerry (talk) 03:31, 9 January 2024 (UTC)

GA to FA
I'm planning on nominating this article for FA by mid-April to early-May. I'll be working on it next week Tuesday; who else wants to join? I'm also working on the narwhal and bonobo articles, so a little help would be really helpful. I feel like it's time this article gets Featured. I already recruited. Wolverine XI ( den • 🐾) 18:07, 9 March 2024 (UTC)

 * I wouldn't mind helping out. I'll look though the stuff I added to the article. I would advise that you try to get a hold of as many sources as possible. Maybe order some books to act as the backbone of your research. There's also Chimpanzee – Wisconsin National Primate Research Center – UW–Madison. You probably shouldn't think too far ahead and work on getting narwhal passed first. LittleJerry (talk) 20:50, 9 March 2024 (UTC)
 * Yes, found 8 books I'd like to utilize for chimpanzees and their lesser known cousins, bonobos. Wolverine XI  ( den • 🐾) 22:39, 9 March 2024 (UTC)
 * , I would also use Gandall's book (certainly cited) since she is a top expert and pioneer. LittleJerry (talk) 19:01, 15 March 2024 (UTC)
 * Who's Gandall? I only know of Jane Goodall. She's one of the reasons why I became highly invested in animals. I began studying animals around 2018, but it was mostly on carnivorous mammals. I'm pretty much new to primate research. Wolverine XI   ( talk to me ) 19:42, 15 March 2024 (UTC)

Use of "Robust"
In the interest of not edit warring with @Wolverine XI, I'm starting a discussion about whether the word robust should be linked to Robustness (morphology). I believe it should, since there are multiple meanings of the word in different fields, and the use of the word robust did confuse me when I first read this article. With Love from Cassie Schebel (talk) 18:52, 16 May 2024 (UTC)

 * Source? Wolverine XI   ( talk to me ) 19:55, 16 May 2024 (UTC)
 * on "there are multiple meanings of the word in different fields" Robustness (disambiguation)
 * "of the word robust did confuse me when I first read this article" is anectodal. With Love from Cassie Schebel (talk) 21:58, 16 May 2024 (UTC)
 * That is not a reliable source. Wolverine XI   ( talk to me ) 04:09, 17 May 2024 (UTC)
 * Not every change needs a reliable source. You did not provide a source when removing the link. This is a matter of Linking, not Quotations. Please use edit summaries more regularly to avoid these issues in the future. With Love from Cassie Schebel (talk) 16:50, 17 May 2024 (UTC)
 * Oh, so I guess this stat is lying then. Wolverine XI   ( talk to me ) 18:32, 17 May 2024 (UTC)
 * Are you serious? I'm trying to solve an issue here. I want to make this article better. I'd appreciate your cooperation. It's certainly good that you leave edit summaries so often -- but you didn't leave one when you removed the link. That's what I was talking about. With Love from Cassie Schebel (talk) 19:25, 17 May 2024 (UTC)

Well, I don't need the wikilink (but then I studied zoology at university albeit many years ago), but what is the harm in the wikilink if someone does think it's useful? I favour restoring it. Peter coxhead (talk) 16:39, 20 May 2024 (UTC)

title: Talk:Chimpanzee


text:
Crystallographic defect

A crystallographic defect is an interruption of the regular patterns of arrangement of atoms or molecules in crystalline solids. The positions and orientations of particles, which are repeating at fixed distances determined by the unit cell parameters in crystals, exhibit a periodic crystal structure, but this is usually imperfect. Several types of defects are often characterized: point defects, line defects, planar defects, bulk defects. Topological homotopy establishes a mathematical method of characterization.

Point defects
Point defects are defects that occur only at or around a single lattice point. They are not extended in space in any dimension. Strict limits for how small a point defect is are generally not defined explicitly. However, these defects typically involve at most a few extra or missing atoms. Larger defects in an ordered structure are usually considered dislocation loops. For historical reasons, many point defects, especially in ionic crystals, are called centers: for example a vacancy in many ionic solids is called a luminescence center, a color center, or F-center. These dislocations permit ionic transport through crystals leading to electrochemical reactions. These are frequently specified using Kröger–Vink notation.

 * Vacancy defects are lattice sites which would be occupied in a perfect crystal, but are vacant. If a neighboring atom moves to occupy the vacant site, the vacancy moves in the opposite direction to the site which used to be occupied by the moving atom. The stability of the surrounding crystal structure guarantees that the neighboring atoms will not simply collapse around the vacancy. In some materials, neighboring atoms actually move away from a vacancy, because they experience attraction from atoms in the surroundings. A vacancy (or pair of vacancies in an ionic solid) is sometimes called a Schottky defect.
 * Interstitial defects are atoms that occupy a site in the crystal structure at which there is usually not an atom. They are generally high energy configurations. Small atoms (mostly impurities) in some crystals can occupy interstices without high energy, such as hydrogen in palladium.

 * A nearby pair of a vacancy and an interstitial is often called a Frenkel defect or Frenkel pair. This is caused when an ion moves into an interstitial site and creates a vacancy.

 * Due to fundamental limitations of material purification methods, materials are never 100% pure, which by definition induces defects in crystal structure. In the case of an impurity, the atom is often incorporated at a regular atomic site in the crystal structure. This is neither a vacant site nor is the atom on an interstitial site and it is called a substitutional defect. The atom is not supposed to be anywhere in the crystal, and is thus an impurity. In some cases where the radius of the substitutional atom (ion) is substantially smaller than that of the atom (ion) it is replacing, its equilibrium position can be shifted away from the lattice site. These types of substitutional defects are often referred to as off-center ions. There are two different types of substitutional defects: Isovalent substitution and aliovalent substitution. Isovalent substitution is where the ion that is substituting the original ion is of the same oxidation state as the ion it is replacing. Aliovalent substitution is where the ion that is substituting the original ion is of a different oxidation state than the ion it is replacing. Aliovalent substitutions change the overall charge within the ionic compound, but the ionic compound must be neutral. Therefore, a charge compensation mechanism is required. Hence either one of the metals is partially or fully oxidised or reduced, or ion vacancies are created.
 * Antisite defects occur in an ordered alloy or compound when atoms of different type exchange positions. For example, some alloys have a regular structure in which every other atom is a different species; for illustration assume that type A atoms sit on the corners of a cubic lattice, and type B atoms sit in the center of the cubes. If one cube has an A atom at its center, the atom is on a site usually occupied by a B atom, and is thus an antisite defect. This is neither a vacancy nor an interstitial, nor an impurity.
 * Topological defects are regions in a crystal where the normal chemical bonding environment is topologically different from the surroundings. For instance, in a perfect sheet of graphite (graphene) all atoms are in rings containing six atoms. If the sheet contains regions where the number of atoms in a ring is different from six, while the total number of atoms remains the same, a topological defect has formed. An example is the Stone Wales defect in nanotubes, which consists of two adjacent 5-membered and two 7-membered atom rings.

 * Amorphous solids may contain defects. These are naturally somewhat hard to define, but sometimes their nature can be quite easily understood. For instance, in ideally bonded amorphous silica all Si atoms have 4 bonds to O atoms and all O atoms have 2 bonds to Si atom. Thus e.g. an O atom with only one Si bond (a dangling bond) can be considered a defect in silica. Moreover, defects can also be defined in amorphous solids based on empty or densely packed local atomic neighbourhoods, and the properties of such 'defects' can be shown to be similar to normal vacancies and interstitials in crystals.
 * Complexes can form between different kinds of point defects. For example, if a vacancy encounters an impurity, the two may bind together if the impurity is too large for the lattice. Interstitials can form 'split interstitial' or 'dumbbell' structures where two atoms effectively share an atomic site, resulting in neither atom actually occupying the site.

Line defects
Line defects can be described by gauge theories.

Dislocations are linear defects, around which the atoms of the crystal lattice are misaligned. There are two basic types of dislocations, the edge dislocation and the screw dislocation. "Mixed" dislocations, combining aspects of both types, are also common.

Edge dislocations are caused by the termination of a plane of atoms in the middle of a crystal. In such a case, the adjacent planes are not straight, but instead bend around the edge of the terminating plane so that the crystal structure is perfectly ordered on either side. The analogy with a stack of paper is apt: if a half a piece of paper is inserted in a stack of paper, the defect in the stack is only noticeable at the edge of the half sheet.

The screw dislocation is more difficult to visualise, but basically comprises a structure in which a helical path is traced around the linear defect (dislocation line) by the atomic planes of atoms in the crystal lattice.

The presence of dislocation results in lattice strain (distortion). The direction and magnitude of such distortion is expressed in terms of a Burgers vector (b). For an edge type, b is perpendicular to the dislocation line, whereas in the cases of the screw type it is parallel. In metallic materials, b is aligned with close-packed crystallographic directions and its magnitude is equivalent to one interatomic spacing.

Dislocations can move if the atoms from one of the surrounding planes break their bonds and rebond with the atoms at the terminating edge.

It is the presence of dislocations and their ability to readily move (and interact) under the influence of stresses induced by external loads that leads to the characteristic malleability of metallic materials.

Dislocations can be observed using transmission electron microscopy, field ion microscopy and atom probe techniques. Deep-level transient spectroscopy has been used for studying the electrical activity of dislocations in semiconductors, mainly silicon.

Disclinations are line defects corresponding to "adding" or "subtracting" an angle around a line. Basically, this means that if you track the crystal orientation around the line defect, you get a rotation. Usually, they were thought to play a role only in liquid crystals, but recent developments suggest that they might have a role also in solid materials, e.g. leading to the self-healing of cracks.

Planar defects

 * Grain boundaries occur where the crystallographic direction of the lattice abruptly changes. This usually occurs when two crystals begin growing separately and then meet.
 * Antiphase boundaries occur in ordered alloys: in this case, the crystallographic direction remains the same, but each side of the boundary has an opposite phase: For example, if the ordering is usually ABABABAB (hexagonal close-packed crystal), an antiphase boundary takes the form of ABABBABA.
 * Stacking faults occur in a number of crystal structures, but the common example is in close-packed structures. They are formed by a local deviation of the stacking sequence of layers in a crystal. An example would be the ABABCABAB stacking sequence.
 * A twin boundary is a defect that introduces a plane of mirror symmetry in the ordering of a crystal. For example, in cubic close-packed crystals, the stacking sequence of a twin boundary would be ABCABCBACBA.
 * On planes of single crystals, steps between atomically flat terraces can also be regarded as planar defects. It has been shown that such defects and their geometry have significant influence on the adsorption of organic molecules

Bulk defects

 * Three-dimensional macroscopic or bulk defects, such as pores, cracks, or inclusions
 * Voids — small regions where there are no atoms, and which can be thought of as clusters of vacancies
 * Impurities can cluster together to form small regions of a different phase. These are often called precipitates.

Mathematical classification methods
A successful mathematical classification method for physical lattice defects, which works not only with the theory of dislocations and other defects in crystals but also, e.g., for disclinations in liquid crystals and for excitations in superfluid 3He, is the topological homotopy theory.

Computer simulation methods
Density functional theory, classical molecular dynamics and kinetic Monte Carlo simulations are widely used to study the properties of defects in solids with computer simulations. Simulating jamming of hard spheres of different sizes and/or in containers with non-commeasurable sizes using the Lubachevsky–Stillinger algorithm can be an effective technique for demonstrating some types of crystallographic defects.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Crystallographic defect


text:
Chomsky normal form

In formal language theory, a context-free grammar, G, is said to be in Chomsky normal form (first described by Noam Chomsky) if all of its production rules are of the form:
 * A → BC,  or
 * A → a,  or
 * S → ε,

where A, B, and C are nonterminal symbols, the letter a is a terminal symbol (a symbol that represents a constant value), S is the start symbol, and ε denotes the empty string. Also, neither B nor C may be the start symbol, and the third production rule can only appear if ε is in L(G), the language produced by the context-free grammar G.

Every grammar in Chomsky normal form is context-free, and conversely, every context-free grammar can be transformed into an equivalent one which is in Chomsky normal form and has a size no larger than the square of the original grammar's size.

Converting a grammar to Chomsky normal form
To convert a grammar to Chomsky normal form, a sequence of simple transformations is applied in a certain order; this is described in most textbooks on automata theory. The presentation here follows Hopcroft, Ullman (1979), but is adapted to use the transformation names from Lange, Leiß (2009). Each of the following transformations establishes one of the properties required for Chomsky normal form.

START: Eliminate the start symbol from right-hand sides
Introduce a new start symbol S0, and a new rule
 * S0 → S,

where S is the previous start symbol. This does not change the grammar's produced language, and S0 will not occur on any rule's right-hand side.

TERM: Eliminate rules with nonsolitary terminals
To eliminate each rule
 * A → X1 ... a ... Xn

with a terminal symbol a being not the only symbol on the right-hand side, introduce, for every such terminal, a new nonterminal symbol Na, and a new rule
 * Na → a.

Change every rule
 * A → X1 ... a ... Xn

to
 * A → X1 ... Na ... Xn.

If several terminal symbols occur on the right-hand side, simultaneously replace each of them by its associated nonterminal symbol. This does not change the grammar's produced language.

BIN: Eliminate right-hand sides with more than 2 nonterminals
Replace each rule
 * A → X1 X2 ... Xn

with more than 2 nonterminals X1,...,Xn by rules
 * A → X1 A1,
 * A1 → X2 A2,
 * An-2 → Xn-1 Xn,
 * An-2 → Xn-1 Xn,

where Ai are new nonterminal symbols. Again, this does not change the grammar's produced language.

DEL: Eliminate ε-rules
An ε-rule is a rule of the form
 * A → ε,

where A is not S0, the grammar's start symbol.

To eliminate all rules of this form, first determine the set of all nonterminals that derive ε. Hopcroft and Ullman (1979) call such nonterminals nullable, and compute them as follows:
 * If a rule A → ε exists, then A is nullable.
 * If a rule A → X1 ... Xn exists, and every single Xi is nullable, then A is nullable, too.

Obtain an intermediate grammar by replacing each rule
 * A → X1 ... Xn

by all versions with some nullable Xi omitted. By deleting in this grammar each ε-rule, unless its left-hand side is the start symbol, the transformed grammar is obtained.

For example, in the following grammar, with start symbol S0,
 * S0 → AbB | C
 * B → AA | AC
 * C → b | c
 * A → a | ε

the nonterminal A, and hence also B, is nullable, while neither C nor S0 is. Hence the following intermediate grammar is obtained:
 * S0 → AbB | AbB | AbB | AbB  |   C
 * B → AA | AA | AA | AεA  |   AC | AC
 * C → b | c
 * A → a | ε

In this grammar, all ε-rules have been "inlined at the call site". In the next step, they can hence be deleted, yielding the grammar:
 * S0 → AbB | Ab | bB | b  |   C
 * B → AA | A  |   AC | C
 * C → b | c
 * A → a

This grammar produces the same language as the original example grammar, viz. {ab,aba,abaa,abab,abac,abb,abc,b,bab,bac,bb,bc,c}, but has no ε-rules.

UNIT: Eliminate unit rules
A unit rule is a rule of the form
 * A → B,

where A, B are nonterminal symbols. To remove it, for each rule
 * B → X1 ... Xn,

where X1 ... Xn is a string of nonterminals and terminals, add rule
 * A → X1 ... Xn

unless this is a unit rule which has already been (or is being) removed. The skipping of nonterminal symbol B in the resulting grammar is possible due to B being a member of the unit closure of nonterminal symbol A.

Order of transformations
When choosing the order in which the above transformations are to be applied, it has to be considered that some transformations may destroy the result achieved by other ones. For example, START will re-introduce a unit rule if it is applied after UNIT. The table shows which orderings are admitted.

Moreover, the worst-case bloat in grammar size depends on the transformation order. Using |G| to denote the size of the original grammar G, the size blow-up in the worst case may range from |G|2 to 22, depending on the transformation algorithm used. The blow-up in grammar size depends on the order between DEL and BIN. It may be exponential when DEL is done first, but is linear otherwise. UNIT can incur a quadratic blow-up in the size of the grammar. The orderings START,TERM,BIN,DEL,UNIT and START,BIN,DEL,UNIT,TERM lead to the least (i.e. quadratic) blow-up.

Example
The following grammar, with start symbol Expr, describes a simplified version of the set of all syntactical valid arithmetic expressions in programming languages like C or Algol60. Both number and variable are considered terminal symbols here for simplicity, since in a compiler front end their internal structure is usually not considered by the parser. The terminal symbol "^" denoted exponentiation in Algol60.

 * Expr
 * → Term
 * | | Expr AddOp Term
 * | | AddOp Term
 * Term
 * → Factor
 * | | Term MulOp Factor
 * Factor
 * → Primary
 * | | Factor ^ Primary
 * Primary
 * → number
 * | | variable
 * | | ( Expr )
 * AddOp
 * | | −
 * MulOp
 * }
 * AddOp
 * | | −
 * MulOp
 * }
 * MulOp
 * }
 * }
 * }
 * }

In step "START" of the above conversion algorithm, just a rule S0→Expr is added to the grammar. After step "TERM", the grammar looks like this:

 * S0
 * → Expr
 * Expr
 * → Term
 * | | Expr AddOp Term
 * | | AddOp Term
 * Term
 * → Factor
 * | | Term MulOp Factor
 * Factor
 * → Primary
 * | | Factor PowOp Primary
 * Primary
 * → number
 * | | variable
 * | | Open Expr Close
 * AddOp
 * | | −
 * MulOp
 * PowOp
 * Open
 * Close
 * }
 * | | −
 * MulOp
 * PowOp
 * Open
 * Close
 * }
 * PowOp
 * Open
 * Close
 * }
 * Open
 * Close
 * }
 * Close
 * }
 * }

After step "BIN", the following grammar is obtained:

 * S0
 * → Expr
 * Expr
 * → Term
 * | | Expr AddOp_Term
 * | | AddOp Term
 * Term
 * → Factor
 * | | Term MulOp_Factor
 * Factor
 * → Primary
 * | | Factor PowOp_Primary
 * Primary
 * → number
 * | | variable
 * | | Open Expr_Close
 * AddOp
 * | | −
 * MulOp
 * PowOp
 * Open
 * Close
 * AddOp_Term
 * colspan=3 | → AddOp Term
 * MulOp_Factor
 * colspan=3 | → MulOp Factor
 * PowOp_Primary
 * colspan=3 | → PowOp Primary
 * Expr_Close
 * colspan=3 | → Expr Close
 * }
 * Open
 * Close
 * AddOp_Term
 * colspan=3 | → AddOp Term
 * MulOp_Factor
 * colspan=3 | → MulOp Factor
 * PowOp_Primary
 * colspan=3 | → PowOp Primary
 * Expr_Close
 * colspan=3 | → Expr Close
 * }
 * MulOp_Factor
 * colspan=3 | → MulOp Factor
 * PowOp_Primary
 * colspan=3 | → PowOp Primary
 * Expr_Close
 * colspan=3 | → Expr Close
 * }
 * colspan=3 | → Expr Close
 * }

Since there are no ε-rules, step "DEL" does not change the grammar. After step "UNIT", the following grammar is obtained, which is in Chomsky normal form:

 * S0
 * → number
 * | | variable
 * | | Open Expr_Close
 * | | Factor PowOp_Primary
 * | | Term MulOp_Factor
 * | | Expr AddOp_Term
 * | | AddOp Term
 * Expr
 * → number
 * | | variable
 * | | Open Expr_Close
 * | | Factor PowOp_Primary
 * | | Term MulOp_Factor
 * | | Expr AddOp_Term
 * | | AddOp Term
 * Term
 * → number
 * | | variable
 * | | Open Expr_Close
 * | | Factor PowOp_Primary
 * | | Term MulOp_Factor
 * Factor
 * → number
 * | | variable
 * | | Open Expr_Close
 * | | Factor PowOp_Primary
 * Primary
 * → number
 * | | variable
 * | | Open Expr_Close
 * AddOp
 * | | −
 * MulOp
 * PowOp
 * Open
 * Close
 * AddOp_Term
 * colspan=3 | → AddOp Term
 * MulOp_Factor
 * colspan=3 | → MulOp Factor
 * PowOp_Primary
 * colspan=3 | → PowOp Primary
 * Expr_Close
 * colspan=3 | → Expr Close
 * }
 * Open
 * Close
 * AddOp_Term
 * colspan=3 | → AddOp Term
 * MulOp_Factor
 * colspan=3 | → MulOp Factor
 * PowOp_Primary
 * colspan=3 | → PowOp Primary
 * Expr_Close
 * colspan=3 | → Expr Close
 * }
 * MulOp_Factor
 * colspan=3 | → MulOp Factor
 * PowOp_Primary
 * colspan=3 | → PowOp Primary
 * Expr_Close
 * colspan=3 | → Expr Close
 * }
 * colspan=3 | → Expr Close
 * }

The Na introduced in step "TERM" are PowOp, Open, and Close. The Ai introduced in step "BIN" are AddOp_Term, MulOp_Factor, PowOp_Primary, and Expr_Close.

Chomsky reduced form
Another way to define the Chomsky normal form is:

A formal grammar is in Chomsky reduced form if all of its production rules are of the form:
 * $$A \rightarrow\, BC$$ or
 * $$A \rightarrow\, a$$,

where $$A$$, $$B$$ and $$C$$ are nonterminal symbols, and $$a$$ is a terminal symbol. When using this definition, $$B$$ or $$C$$ may be the start symbol. Only those context-free grammars which do not generate the empty string can be transformed into Chomsky reduced form.

Floyd normal form
In a letter where he proposed a term Backus–Naur form (BNF), Donald E. Knuth implied a BNF "syntax in which all definitions have such a form may be said to be in 'Floyd Normal Form'",
 * $$\langle A \rangle ::= \, \langle B \rangle \mid \langle C \rangle$$ or
 * $$\langle A \rangle ::= \, \langle B \rangle \langle C \rangle$$ or
 * $$\langle A \rangle ::=\, a$$,

where $$\langle A \rangle$$, $$\langle B \rangle$$ and $$\langle C \rangle$$ are nonterminal symbols, and $$a$$ is a terminal symbol, because Robert W. Floyd found any BNF syntax can be converted to the above one in 1961. But he withdrew this term, "since doubtless many people have independently used this simple fact in their own work, and the point is only incidental to the main considerations of Floyd's note." While Floyd's note cites Chomsky's original 1959 article, Knuth's letter does not.

Application
Besides its theoretical significance, CNF conversion is used in some algorithms as a preprocessing step, e.g., the CYK algorithm, a bottom-up parsing for context-free grammars, and its variant probabilistic CKY.

title: Chomsky normal form


text:
Comprehensive Nuclear-Test-Ban Treaty

The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is a multilateral treaty to ban nuclear weapons test explosions and any other nuclear explosions, for both civilian and military purposes, in all environments. It was adopted by the United Nations General Assembly on 10 September 1996, but has not entered into force, as eight specific nations have not ratified the treaty.

History
The movement for international control of nuclear weapons began in 1945, with a call from Canada and the United Kingdom for a conference on the subject. In June 1946, Bernard Baruch, an emissary of President Harry S. Truman, proposed the Baruch Plan before the United Nations Atomic Energy Commission, which called for an international system of controls on the production of atomic energy. The plan, which would serve as the basis for U.S. nuclear policy into the 1950s, was rejected by the Soviet Union as a US ploy to cement its nuclear dominance.

Between the Trinity nuclear test of 16 July 1945 and the signing of the Partial Test Ban Treaty (PTBT) on 5 August 1963, 499 nuclear tests were conducted. Much of the impetus for the PTBT, the precursor to the CTBT, was rising public concern surrounding the size and resulting nuclear fallout from underwater and atmospheric nuclear tests, particularly tests of powerful thermonuclear weapons (hydrogen bombs). The Castle Bravo test of 1 March 1954, in particular, attracted significant attention as the detonation resulted in fallout that spread over inhabited areas and sickened a group of Japanese fishermen. Between 1945 and 1963, the US conducted 215 atmospheric tests, the Soviet Union conducted 219, the UK conducted 21, and France conducted 4.

In 1954, following the Castle Bravo test, Prime Minister Jawaharlal Nehru of India issued the first appeal for a "standstill agreement" on testing, which was soon echoed by the British Labour Party. Negotiations on a comprehensive test ban, primarily involving the US, UK, and the Soviet Union, began in 1955 following a proposal by Soviet leader Nikita Khrushchev. Of primary concern throughout the negotiations, which would stretch—with some interruptions—to July 1963, was the system of verifying compliance with the test ban and detecting illicit tests. On the Western side, there were concerns that the Soviet Union would be able to circumvent any test ban and secretly leap ahead in the nuclear arms race. These fears were amplified following the US Rainier shot of 19 September 1957, which was the first contained underground test of a nuclear weapon. Though the US held a significant advantage in underground testing capabilities, there was worry that the Soviet Union would be able to covertly conduct underground tests during a test ban, as underground detonations were more challenging to detect than above-ground tests. On the Soviet side, conversely, the on-site compliance inspections demanded by the US and UK were seen as amounting to espionage. Disagreement over verification would lead to the Anglo-American and Soviet negotiators abandoning a comprehensive test ban (i.e., a ban on all tests, including those underground) in favor of a partial ban, which would be finalized on 25 July 1963. The PTBT, joined by 123 states following the original three parties, banned detonations for military and civilian purposes underwater, in the atmosphere, and outer space.

The PTBT had mixed results. On the one hand, enactment of the treaty was followed by a substantial drop in the atmospheric concentration of radioactive particles. On the other hand, nuclear proliferation was not halted entirely (though it may have been slowed) and nuclear testing continued at a rapid clip. Compared to the 499 tests from 1945 to the signing of the PTBT, 436 tests were conducted over the ten years following the PTBT. Furthermore, US and Soviet underground testing continued "venting" radioactive gas into the atmosphere. Additionally, though underground testing was generally safer than above-ground testing, underground tests continued to risk the leaking of radionuclides, including plutonium, into the ground. From 1964 through 1996, the year of the CTBT's adoption, an estimated 1,377 underground nuclear tests were conducted. The final non-underground (atmospheric or underwater) test was conducted by China in 1980.

The PTBT has been seen as a step towards the Nuclear Non-proliferation Treaty (NPT) of 1968, which directly referenced the PTBT. Under the NPT, non-nuclear weapon states were prohibited from possessing, manufacturing, and acquiring nuclear weapons or other nuclear explosive devices. All signatories, including nuclear weapon states, were committed to the goal of total nuclear disarmament. However, India, Pakistan, and Israel have declined to sign the NPT on the grounds that such a treaty is fundamentally discriminatory as it places limitations on states that do not have nuclear weapons while making no efforts to curb weapons development by declared nuclear weapons states.

In 1974, a step towards a comprehensive test ban was made with the Threshold Test Ban Treaty (TTBT), ratified by the US and Soviet Union, which banned underground tests with yields above 150 kilotons. In April 1976, the two states reached agreement on the Peaceful Nuclear Explosions Treaty (PNET), which concerns nuclear detonations outside the weapons sites discussed in the TTBT. As in the TTBT, the US and Soviet Union agreed to bar peaceful nuclear explosions (PNEs) at these other locations with yields above 150 kilotons, as well as group explosions with total yields over 1,500 kilotons. To verify compliance, the PNET requires that states rely on national technical means of verification, share information on explosions, and grant on-site access to counterparties. The TTBT and PNET entered into force on 11 December 1990.

In October 1977, the US, UK, and Soviet Union returned to negotiations over a test ban. These three nuclear powers made notable progress in the late 1970s, agreeing to terms on a ban on all testing, including a temporary prohibition on PNEs, but continued disagreements over the compliance mechanisms led to an end to negotiations ahead of Ronald Reagan's inauguration as president in 1981. In 1985, Soviet leader Mikhail Gorbachev announced a unilateral testing moratorium, and in December 1986, Reagan reaffirmed US commitment to pursue the long-term goal of a comprehensive test ban. In November 1987, negotiations on a test ban restarted, followed by a joint US-Soviet program to research underground-test detection in December 1987.

In October 2023, Russian president Vladimir Putin stated that since the United States had not ratified the CTBT, consideration could be given to withdrawing Russia's ratification of the treaty. Later in the month, a law revoking ratification of the CTBT was passed by the Russian parliament. On 2 November, Putin officially signed into law the withdrawal of ratification of the treaty.

Negotiations
Given the political situation prevailing in the subsequent decades, little progress was made in nuclear disarmament until the end of the Cold War in 1991. Parties to the PTBT held an amendment conference that year to discuss a proposal to convert the Treaty into an instrument banning all nuclear-weapon tests. With strong support from the UN General Assembly, negotiations for a comprehensive test-ban treaty began in 1993.

Adoption
Extensive efforts were made over the next three years to draft the Treaty text and its two annexes. However, the Conference on Disarmament, in which negotiations were being held, did not succeed in reaching consensus on the adoption of the text. Under the direction of Prime Minister John Howard and Foreign Minister Alexander Downer, Australia then sent the text to the United Nations General Assembly in New York, where it was submitted as a draft resolution. On 10 September 1996, the Comprehensive Test-Ban Treaty (CTBT) was adopted by a large majority, exceeding two-thirds of the General Assembly's Membership.

Obligations
(Article I):
 * 1) Each State Party undertakes not to carry out any nuclear weapon test explosion or any other nuclear explosion, and to prohibit and prevent any such nuclear explosion at any place under its jurisdiction or control.
 * 2) Each State Party undertakes, furthermore, to refrain from causing, encouraging, or in any way participating in the carrying out of any nuclear weapon test explosion or any other nuclear explosion.

Status
The Treaty was adopted by the United Nations General Assembly on 10 September 1996. It opened for signature in New York on 24 September 1996, when it was signed by 71 states, including five of the eight then nuclear-capable states. , 178 states have ratified the CTBT and another nine states have signed but not ratified it.

The treaty will enter into force 180 days after the 44 states listed in Annex 2 of the treaty have ratified it. These "Annex 2 states" are states that participated in the CTBT's negotiations between 1994 and 1996 and possessed nuclear power reactors or research reactors at that time. , nine Annex 2 states have not ratified the treaty: China, Egypt, Iran, Israel and the United States have signed but not ratified the Treaty; India, North Korea and Pakistan have not signed it; while Russia signed and ratified the treaty but subsequently withdrew its ratification prior to its entry into force.

Monitoring
Geophysical and other technologies are used to monitor for compliance with the Treaty: forensic seismology, hydroacoustics, infrasound, and radionuclide monitoring. The first three forms of monitoring are known as wave-form measurements. Seismic monitoring is performed with a system of 50 primary stations located throughout the world, with 120 auxiliary stations in signatory states. Hydroacoustic monitoring is performed with a system of 11 stations that consist of hydrophone triads to monitor for underwater explosions. Hydroacoustic stations can use seismometers to measure T-waves from possible underwater explosions instead of hydrophones. The best measurement of hydroacoustic waves has been found to be at a depth of 1000 m. Infrasound monitoring relies on changes in atmospheric pressure caused by a possible nuclear explosion, with 41 stations certified as of August 2019. One of the biggest concerns with infrasound measurements is noise due to exposure from wind, which can affect the sensor's ability to measure if an event occurred. Together, these technologies are used to monitor the ground, water, and atmosphere for any sign of a nuclear explosion.

Radionuclide monitoring takes the form of either monitoring for radioactive particulates or noble gases as a product of a nuclear explosion. Radioactive particles emit radiation that can be measured by any of the 80 stations located throughout the world. They are created from nuclear explosions that can collect onto the dust that is moved from the explosion. If a nuclear explosion took place underground, noble gas monitoring can be used to verify whether or not a possible nuclear explosion took place. Noble gas monitoring relies on measuring increases in radioactive xenon gas. Different isotopes of xenon include 131mXe, 133Xe, 133mXe, and 135Xe. All four monitoring methods make up the International Monitoring System (IMS). Statistical theories and methods are integral to CTBT monitoring providing confidence in verification analysis. Once the Treaty enters into force, on-site inspections will be conducted where concerns about compliance arise.

The Preparatory Commission for the Comprehensive Test Ban Treaty Organization (CTBTO), an international organization headquartered in Vienna, Austria, was created to build the verification framework, including establishment and provisional operation of the network of monitoring stations, the creation of an international data centre (IDC), and development of the on-site Inspection capability. The CTBTO is responsible for collecting information from the IMS and distribute the analyzed and raw data to member states to judge whether or not a nuclear explosion occurred through the IDC. Parameters such as determining the location where a nuclear explosion or test took place is one of the things that the IDC can accomplish. If a member state chooses to assert that another state had violated the CTBT, they can request an on-site inspection to take place to verify.

The monitoring network consists of 337 facilities located all over the globe. As of May 2012, more than 260 facilities have been certified. The monitoring stations register data that is transmitted to the international data centre in Vienna for processing and analysis. The data are sent to states that have signed the Treaty.

Subsequent nuclear testing
Three countries have tested nuclear weapons since the CTBT opened for signature in 1996. India and Pakistan both carried out two sets of tests in 1998. North Korea carried out six announced tests, one each in 2006, 2009, 2013, two in 2016 and one in 2017. All six North Korean tests were picked up by the International Monitoring System set up by the Comprehensive Nuclear-Test-Ban Treaty Organization Preparatory Commission. A North Korean test is believed to have taken place in January 2016, evidenced by an "artificial earthquake" measured as a magnitude 5.1 by the U.S. Geological Survey. The first successful North Korean hydrogen bomb test supposedly took place in September 2017. It was estimated to have an explosive yield of 120 kilotons.

title: Comprehensive Nuclear-Test-Ban Treaty


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Dance

Dance is an art form, often classified as a sport, consisting of sequences of body movements with aesthetic and often symbolic value, either improvised or purposefully selected. Dance can be categorized and described by its choreography, by its repertoire of movements or by its historical period or place of origin. Dance is typically performed with musical accompaniment, and sometimes with the dancer simultaneously using a musical instrument themselves.

An important distinction is to be drawn between theatrical and participatory dance, although these two categories are not always completely separate; both may have special functions, whether social, ceremonial, competitive, erotic, martial, sacred or liturgical. Other forms of human movement are sometimes said to have a dance-like quality, including martial arts, gymnastics, cheerleading, figure skating, synchronized swimming, marching bands, and many other forms of athletics. Dance is not solely restricted to performance, as dance is used as a form of exercise and occasionally training for other sports and activities. Dance has become a sport for some, with dancing competitions found across the world exhibiting various different styles and standards. Dance has an aesthetic appeal to many people.

Theatrical and participatory dance
Theatrical dance, also called performance or concert dance, is intended primarily as a spectacle, usually a performance upon a stage by virtuoso dancers. It often tells a story, perhaps using mime, costume and scenery, or it may interpret the musical accompaniment, which is often specially composed and performed in a theatre setting but it is not a requirement. Examples are Western ballet and modern dance, Classical Indian dance such as Bharatanatyam, and Chinese and Japanese song and dance dramas, such as the dragon dance. Most classical forms are centred upon dance alone, but performance dance may also appear in opera and other forms of musical theatre.

Participatory dance, whether it be a folk dance, a social dance, a group dance such as a line, circle, chain or square dance, or a partner dance, such as in Western ballroom dancing, is undertaken primarily for a common purpose, such as social interaction or exercise, or building flexibility of participants rather than to serve any benefit to onlookers. Such dance seldom has any narrative. A group dance and a corps de ballet, a social partner dance and a pas de deux, differ profoundly. Even a solo dance or interpretive dance may be undertaken solely for the satisfaction of the dancer. Participatory dancers often all employ the same movements and steps but, for example, in the rave culture of electronic dance music, vast crowds may engage in free dance, uncoordinated with those around them. On the other hand, some cultures lay down strict rules as to the particular dances people may or must participate.

History
Archaeological evidence for early dance includes 10,000-years-old paintings in Madhya Pradesh, India at the Rock Shelters of Bhimbetka, and Egyptian tomb paintings depicting dancing figures, dated c. 3300 BC. It has been proposed that before the invention of written languages, dance was an important part of the oral and performance methods of passing stories down from one generation to the next. The use of dance in ecstatic trance states and healing rituals (as observed today in many contemporary indigenous cultures) is thought to have been another early factor in the social development of dance. References to dance can be found in very early recorded history; Greek dance (choros) is referred to by Plato, Aristotle, Plutarch and Lucian. The Bible and Talmud refer to many events related to dance, and contain over 30 different dance terms. In Chinese pottery as early as the Neolithic period, groups of people are depicted dancing in a line holding hands, and the earliest Chinese word for "dance" is found written in the oracle bones. Dance is described in the Lüshi Chunqiu. Primitive dance in ancient China was associated with sorcery and shamanic rituals. During the first millennium BCE in India, many texts were composed which attempted to codify aspects of daily life. Bharata Muni's Natya Shastra (literally "the text of dramaturgy") is one early text. It mainly deals with drama, in which dance plays an important part in Indian culture. A strong continuous tradition of dance has since continued in India, through to modern times, where it continues to play a role in culture, ritual, and the Bollywood entertainment industry. Many other contemporary dance forms can likewise be traced back to historical, traditional, ceremonial, and ethnic dance.

Music
Dance is generally, but not exclusively, performed with the accompaniment of music and may or may not be performed in time to such music. Some dance (such as tap dance or gumboot dance) may provide its own audible accompaniment in place of (or in addition to) music. Many early forms of music and dance were created for each other and are frequently performed together. Notable examples of traditional dance-music couplings include the jig, waltz, tango, disco, and salsa. Some musical genres have a parallel dance form such as baroque music and baroque dance; other varieties of dance and music may share nomenclature but developed separately, such as classical music and classical ballet. The choreography and music are meant to complement each other, to express a story told by the choreographer and dancers.

Rhythm
Rhythm and dance are deeply linked in history and practice. The American dancer Ted Shawn wrote; "The conception of rhythm which underlies all studies of the dance is something about which we could talk forever, and still not finish." A musical rhythm requires two main elements; first, a regularly-repeating pulse (also called the "beat" or "tactus") that establishes the tempo and, second, a pattern of accents and rests that establishes the character of the metre or basic rhythmic pattern. The basic pulse is roughly equal in duration to a simple step or gesture. Dances generally have a characteristic tempo and rhythmic pattern. The tango, for example, is usually danced in time at approximately 66 beats per minute. The basic slow step, called a "slow", lasts for one beat, so that a full "right–left" step is equal to one measure. The basic forward and backward walk of the dance is so counted – "slow-slow" – while many additional figures are counted "slow – quick-quick".

Repetitive body movements often depend on alternating "strong" and "weak" muscular movements. Given this alternation of left-right, of forward-backward and rise-fall, along with the bilateral symmetry of the human body, many dances and much music are in duple and quadruple meter. Since some such movements require more time in one phase than the other – such as the longer time required to lift a hammer than to strike – some dance rhythms fall into triple metre. Occasionally, as in the folk dances of the Balkans, dance traditions depend heavily on more complex rhythms. Further, complex dances composed of a fixed sequence of steps always require phrases and melodies of a certain fixed length to accompany that sequence.

Musical accompaniment arose in the earliest dance, so that ancient Egyptians attributed the origin of the dance to the divine Athotus, who was said to have observed that music accompanying religious rituals caused participants to move rhythmically and to have brought these movements into proportional measure. The same idea, that dance arises from musical rhythm, was found in renaissance Europe, in the works of the dancer Guglielmo Ebreo da Pesaro, who speaks of dance as a physical movement that arises from and expresses inward, spiritual motion agreeing with the "measures and perfect concords of harmony" that fall upon the human ear, while, earlier, Mechthild of Magdeburg, seizing upon dance as a symbol of the holy life foreshadowed in Jesus' saying "I have piped and ye have not danced", writes;

"I can not dance unless thou leadest. If thou wouldst have me spring aloft, sing thou and I will spring, into love and from love to knowledge and from knowledge to ecstasy above all human sense"

Thoinot Arbeau's celebrated 16th-century dance-treatise Orchésographie, indeed, begins with definitions of over eighty distinct drum-rhythms.

As has been shown above, dance has been represented through the ages as having emerged as a response to music yet, as Lincoln Kirstein implied, it is at least as likely that primitive music arose from dance. Shawn concurs, stating that dance "was the first art of the human race, and the matrix out of which all other arts grew" and that even the "metre in our poetry today is a result of the accents necessitated by body movement, as the dancing and reciting was performed simultaneously" – an assertion somewhat supported by the common use of the term "foot" to describe the fundamental rhythmic units of poetry.

Scholes, not a dancer but a musician, offers support for this view, stating that the steady measures of music, of two, three or four beats to the bar, its equal and balanced phrases, regular cadences, contrasts and repetitions, may all be attributed to the "incalculable" influence of dance upon music.

Émile Jaques-Dalcroze, primarily a musician and teacher, relates how a study of the physical movements of pianists led him "to the discovery that musical sensations of a rhythmic nature call for the muscular and nervous response of the whole organism", to develop "a special training designed to regulate nervous reactions and effect a co-ordination of muscles and nerves" and ultimately to seek the connections between "the art of music and the art of dance", which he formulated into his system of eurhythmics. He concluded that "musical rhythm is only the transposition into sound of movements and dynamisms spontaneously and involuntarily expressing emotion".

Hence, though doubtless, as Shawn asserts, "it is quite possible to develop the dance without music and... music is perfectly capable of standing on its own feet without any assistance from the dance", nevertheless the "two arts will always be related and the relationship can be profitable both to the dance and to music", the precedence of one art over the other being a moot point. The common ballad measures of hymns and folk-songs takes their name from dance, as does the carol, originally a circle dance. Many purely musical pieces have been named "waltz" or "minuet", for example, while many concert dances have been produced that are based upon abstract musical pieces, such as 2 and 3 Part Inventions, Adams Violin Concerto and Andantino. Similarly, poems are often structured and named after dances or musical works, while dance and music have both drawn their conception of "measure" or "metre" from poetry.

Shawn quotes with approval the statement of Dalcroze that, while the art of musical rhythm consists in differentiating and combining time durations, pauses and accents "according to physiological law", that of "plastic rhythm" (i.e. dance) "is to designate movement in space, to interpret long time-values by slow movements and short ones by quick movements, regulate pauses by their divers successions and express sound accentuations in their multiple nuances by additions of bodily weight, by means of muscular innervations".

Shawn nevertheless points out that the system of musical time is a "man-made, artificial thing.... a manufactured tool, whereas rhythm is something that has always existed and depends on man not at all", being "the continuous flowing time which our human minds cut up into convenient units", suggesting that music might be revivified by a return to the values and the time-perception of dancing.

The early-20th-century American dancer Helen Moller stated that "it is rhythm and form more than harmony and color which, from the beginning, has bound music, poetry and dancing together in a union that is indissoluble."

Theatrical
Concert dance, like opera, generally depends for its large-scale form upon a narrative dramatic structure. The movements and gestures of the choreography are primarily intended to mime the personality and aims of the characters and their part in the plot. Such theatrical requirements tend towards longer, freer movements than those usual in non-narrative dance styles. On the other hand, the ballet blanc, developed in the 19th century, allows interludes of rhythmic dance that developed into entirely "plotless" ballets in the 20th century and that allowed fast, rhythmic dance-steps such as those of the petit allegro. A well-known example is The Cygnets' Dance in act two of Swan Lake.

The ballet developed out of courtly dramatic productions of 16th- and 17th-century France and Italy and for some time dancers performed dances developed from those familiar from the musical suite, all of which were defined by definite rhythms closely identified with each dance. These appeared as character dances in the era of romantic nationalism.

Ballet reached widespread vogue in the romantic era, accompanied by a larger orchestra and grander musical conceptions that did not lend themselves easily to rhythmic clarity and by dance that emphasised dramatic mime. A broader concept of rhythm was needed, that which Rudolf Laban terms the "rhythm and shape" of movement that communicates character, emotion and intention, while only certain scenes required the exact synchronisation of step and music essential to other dance styles, so that, to Laban, modern Europeans seemed totally unable to grasp the meaning of "primitive rhythmic movements", a situation that began to change in the 20th century with such productions as Igor Stravinsky's The Rite of Spring with its new rhythmic language evoking primal feelings of a primitive past.

Indian classical dance styles, like ballet, are often in dramatic form, so that there is a similar complementarity between narrative expression and "pure" dance. In this case, the two are separately defined, though not always separately performed. The rhythmic elements, which are abstract and technical, are known as nritta. Both this and expressive dance (nritya), though, are closely tied to the rhythmic system (tala). Teachers have adapted the spoken rhythmic mnemonic system called bol to the needs of dancers.

Japanese classical dance-theatre styles such as Kabuki and Noh, like Indian dance-drama, distinguish between narrative and abstract dance productions. The three main categories of kabuki are jidaimono (historical), sewamono (domestic) and shosagoto (dance pieces). Somewhat similarly, Noh distinguishes between Geki Noh, based around the advancement of plot and the narration of action, and Furyū Noh, dance pieces involving acrobatics, stage properties, multiple characters and elaborate stage action.

Participatory and social
Social dances, those intended for participation rather than for an audience, may include various forms of mime and narrative, but are typically set much more closely to the rhythmic pattern of music, so that terms like waltz and polka refer as much to musical pieces as to the dance itself. The rhythm of the dancers' feet may even form an essential part of the music, as in tap dance. African dance, for example, is rooted in fixed basic steps, but may also allow a high degree of rhythmic interpretation: the feet or the trunk mark the basic pulse while cross-rhythms are picked up by shoulders, knees, or head, with the best dancers simultaneously giving plastic expression to all the elements of the polyrhythmic pattern.

Africa

Dance in Africa is deeply integrated into society and major events in a community are frequently reflected in dances: dances are performed for births and funerals, weddings and wars. Traditional dances impart cultural morals, including religious traditions and sexual standards; give vent to repressed emotions, such as grief; motivate community members to cooperate, whether fighting wars or grinding grain; enact spiritual rituals; and contribute to social cohesiveness.

Thousands of dances are performed around the continent. These may be divided into traditional, neotraditional, and classical styles: folkloric dances of a particular society, dances created more recently in imitation of traditional styles, and dances transmitted more formally in schools or private lessons. African dance has been altered by many forces, such as European missionaries and colonialist governments, who often suppressed local dance traditions as licentious or distracting. Dance in contemporary African cultures still serves its traditional functions in new contexts; dance may celebrate the inauguration of a hospital, build community for rural migrants in unfamiliar cities, and be incorporated into Christian church ceremonies.

Asia
All Indian classical dances are to varying degrees rooted in the Natyashastra and therefore share common features: for example, the mudras (hand positions), some body positions, leg movement and the inclusion of dramatic or expressive acting or abhinaya. Indian classical music provides accompaniment and dancers of nearly all the styles wear bells around their ankles to counterpoint and complement the percussion.

There are now many regional varieties of Indian classical dance. Dances like "Odra Magadhi", which after decades-long debate, has been traced to present day Mithila, Odisha region's dance form of Odissi (Orissi), indicate influence of dances in cultural interactions between different regions.

The Punjab area overlapping India and Pakistan is the place of origin of Bhangra. It is widely known both as a style of music and a dance. It is mostly related to ancient harvest celebrations, love, patriotism or social issues. Its music is coordinated by a musical instrument called the 'Dhol'. Bhangra is not just music but a dance, a celebration of the harvest where people beat the dhol (drum), sing Boliyaan (lyrics) and dance. It developed further with the Vaisakhi festival of the Sikhs.

The dances of Sri Lanka include the devil dances (yakun natima), a carefully crafted ritual reaching far back into Sri Lanka's pre-Buddhist past that combines ancient "Ayurvedic" concepts of disease causation with psychological manipulation and combines many aspects including Sinhalese cosmology. Their influence can be seen on the classical dances of Sri Lanka.

Indonesian dances reflect the richness and diversity of Indonesian ethnic groups and cultures. There are more than 1,300 ethnic groups in Indonesia, it can be seen from the cultural roots of the Austronesian and Melanesian peoples, and various cultural influences from Asia and the west. Dances in Indonesia originate from ritual movements and religious ceremonies, this kind of dance usually begins with rituals, such as war dances, shaman dances to cure or ward off disease, dances to call rain and other types of dances. With the acceptance of dharma religion in the 1st century in Indonesia, Hinduism and Buddhist rituals were celebrated in various artistic performances. Hindu epics such as the Ramayana, Mahabharata and also the Panji became the inspiration to be shown in a dance-drama called "Sendratari" resembling "ballet" in the western tradition. An elaborate and highly stylized dance method was invented and has survived to this day, especially on the islands of Java and Bali. The Javanese Wayang wong dance takes footage from the Ramayana or Mahabharata episodes, but this dance is very different from the Indian version, indonesian dances do not pay as much attention to the "mudras" as Indian dances: even more to show local forms. The sacred Javanese ritual dance Bedhaya is believed to date back to the Majapahit period in the 14th century or even earlier, this dance originated from ritual dances performed by virgin girls to worship Hindu Gods such as Shiva, Brahma, and Vishnu. In Bali, dance has become an integral part of the sacred Hindu Dharma rituals. Some experts believe that Balinese dance comes from an older dance tradition from Java. Reliefs from temples in East Java from the 14th century feature crowns and headdresses similar to the headdresses used in Balinese dance today. Islam began to spread to the Indonesian archipelago when indigenous dances and dharma dances were still popular. Artists and dancers still use styles from the previous era, replacing stories with more Islamic interpretations and clothing that is more closed according to Islamic teachings.

The dances of the Middle East are usually the traditional forms of circle dancing which are modernized to an extent. They would include dabke, tamzara, Assyrian folk dance, Kurdish dance, Armenian dance and Turkish dance, among others. All these forms of dances would usually involve participants engaging each other by holding hands or arms (depending on the style of the dance). They would make rhythmic moves with their legs and shoulders as they curve around the dance floor. The head of the dance would generally hold a cane or handkerchief.

Europe and North America
Folk dances vary across Europe and may date back hundreds or thousands of years, but many have features in common such as group participation led by a caller, hand-holding or arm-linking between participants, and fixed musical forms known as caroles. Some, such as the maypole dance are common to many nations, while others such as the céilidh and the polka are deeply-rooted in a single culture. Some European folk dances such as the square dance were brought to the New World and subsequently became part of American culture.

Ballet developed first in Italy and then in France from lavish court spectacles that combined rhythm, drama, poetry, song, costumes and dance. Members of the court nobility took part as performers. During the reign of Louis XIV, himself a dancer, dance became more codified. Professional dancers began to take the place of court amateurs, and ballet masters were licensed by the French government. The first ballet dance academy was the Académie Royale de Danse (Royal Dance Academy), opened in Paris in 1661. Shortly thereafter, the first institutionalized ballet troupe, associated with the Academy, was formed; this troupe began as an all-male ensemble but by 1681 opened to include women as well.

20th century concert dance brought an explosion of innovation in dance style characterized by an exploration of freer technique. Early pioneers of what became known as modern dance include Loie Fuller, Isadora Duncan, Mary Wigman and Ruth St. Denis. The relationship of music to dance serves as the basis for Eurhythmics, devised by Emile Jaques-Dalcroze, which was influential to the development of Modern dance and modern ballet through artists such as Marie Rambert. Eurythmy, developed by Rudolf Steiner and Marie Steiner-von Sivers, combines formal elements reminiscent of traditional dance with the new freer style, and introduced a complex new vocabulary to dance. In the 1920s, important founders of the new style such as Martha Graham and Doris Humphrey began their work. Since this time, a wide variety of dance styles have been developed; see Modern dance.

African American dance developed in everyday spaces, rather than in dance studios, schools or companies. Tap dance, disco, jazz dance, swing dance, hip hop dance, the lindy hop with its relationship to rock and roll music and rock and roll dance have had a global influence. Dance styles fusing classical ballet technique with African-American dance have also appeared in the 21st century, including Hiplet.

Latin America
Dance is central to Latin American social life and culture. Brazilian Samba, Argentinian tango, and Cuban salsa are internationally popular partner dances, and other national dances—merengue, cueca, plena, jarabe, joropo, marinera, cumbia, bachata and others—are important components of their respective countries' cultures. Traditional Carnival festivals incorporate these and other dances in enormous celebrations.

Dance has played an important role in forging a collective identity among the many cultural and ethnic groups of Latin America. Dance served to unite the many African, European, and indigenous peoples of the region. Certain dance genres, such as capoeira, and body movements, especially the characteristic quebradas or pelvis swings, have been variously banned and celebrated throughout Latin American history.

Education
Dance studies are offered through the arts and humanities programs of many higher education institutions. Some universities offer Bachelor of Arts and higher academic degrees in Dance. A dance study curriculum may encompass a diverse range of courses and topics, including dance practice and performance, choreography, ethnochoreology, kinesiology, dance notation, and dance therapy. Most recently, dance and movement therapy has been integrated in some schools into math lessons for students with learning disabilities, emotional or behavioral disabilities, as well as for those with attention deficit hyperactivity disorder (ADHD).

Dancers
Professional dancers are usually employed on contract or for particular performances or productions. The professional life of a dancer is generally one of constantly changing work situations, strong competitive pressure and low pay. Consequently, professional dancers often must supplement their incomes to achieve financial stability. In the U.S. many professional dancers belong to unions (such as the American Guild of Musical Artists, Screen Actors Guild and Actors' Equity Association) that establish working conditions and minimum salaries for their members. Professional dancers must possess large amounts of athleticism. To lead a successful career, it is advantageous to be versatile in many styles of dance, have a strong technical background and to use other forms of physical training to remain fit and healthy.

Teachers
Dance teachers typically focus on teaching dance performance, or coaching competitive dancers, or both. They typically have performance experience in the types of dance they teach or coach. For example, dancesport teachers and coaches are often tournament dancers or former dancesport performers. Dance teachers may be self-employed, or employed by dance schools or general education institutions with dance programs. Some work for university programs or other schools that are associated with professional classical dance (e.g., ballet) or modern dance companies. Others are employed by smaller, privately owned dance schools that offer dance training and performance coaching for various types of dance.

Choreographers
Choreographers are the ones that design the dancing movements within a dance, they are often university trained and are typically employed for particular projects or, more rarely may work on contract as the resident choreographer for a specific dance company.

Competitions

A dance competition is an organized event in which contestants perform dances before a judge or judges for awards, and in some cases, monetary prizes. There are several major types of dance competitions, distinguished primarily by the style or styles of dances performed. Dance competitions are an excellent setting to build connections with industry leading faculty members, adjudicators, choreographers and other dancers from competing studios. A typical dance competition for younger pre-professional dancers can last anywhere between two and four days, depending whether it is a regional or national competition.

The purpose of dance competitions is to provide a fun and educative place for dancers and give them the opportunity to perform their choreographed routines from their current dance season onstage. Oftentimes, competitions will take place in a professional setting or may vary to non-performance spaces, such as a high school theatre. The results of the dancers are then dictated by a credible panel of judges and are evaluated on their performance than given a score. As far as competitive categories go, most competitions base their categories according to the dance style, age, experience level and the number of dancers competing in the routine. Major types of dance competitions include:

 * Dancesport, which is focused exclusively on ballroom and latin dance.
 * Competitive dance, in which a variety of theater dance styles, such as acrobatics, ballet, jazz, hip-hop, lyrical, stepping, and tap, are permitted.
 * Commercial Dance, consisting of as hip hop, jazz, locking, popping, breakdancing, contemporary etc.
 * Single-style competitions, such as; highland dance, dance team, and Irish dance, that only permit a single dance style.
 * Open competitions, that permit a wide variety of dance styles. An example of this is the TV program So You Think You Can Dance.
 * Olympic, Dance has been trying to be part of the Olympic sport since 1930s.

Dance diplomacy
During the 1950s and 1960s, cultural exchange of dance was a common feature of international diplomacy, especially amongst East and South Asian nations. The People's Republic of China, for example, developed a formula for dance diplomacy that sought to learn from and express respect for the aesthetic traditions of recently independent states that were former European colonies, such as Indonesia, India, and Burma, as a show of anti-colonial solidarity.

Footwear
In most forms of dance the foot is the source of movement, and in some cases require specific shoes to aid in the health, safety ability of the dancer, depending on the type of dance, the intensity of the movements, and the surface that will be danced on.

Dance footwear can be potentially both supportive and or restrictive to the movement of the dancer. The effectiveness of the shoe is related to its ability to help the foot do something it is not intended to do, or to make easier a difficult movement. Such effects relate to health and safety because of the function of the equipment as unnatural to the bodies usual mobility.

Ballet
Ballet is notable for the risks of injury due to the biomechanics of the ankle and the toes as the main support for the rest of the movements. With the pointe shoe, the design specifically brings all of the toes together to allow the toes to be stood on for longer periods of time.

There are accessories associated with pointe shoes that help to mitigate injury and soothe pain while dancing, including things such as toe pads, toe tape, and cushions.

Body image
Dancers are publicly thought to be very preoccupied with their body image to fit a certain mold in the industry. Research indicates that dancers do have greater difficulty controlling their eating habits as a large quantity strive for the art-form's ideal body mass. Some dancers often resort to abusive tactics to maintain a certain image. Common scenarios include dancers abusing laxatives for weight control and end up falling into unhealthy eating disorders. Studies show that a large quantity of dancers use at least one method of weight control including over exercising and food restriction. The pressure for dancers to maintain a below average weight affects their eating and weight controlling behaviours and their life-style. Due to its artistic nature, dancers tend to have many hostile self-critical tendencies. Commonly seen in performers, it is likely that a variety of individuals may be resistant to concepts of self-compassion.

Eating disorders
In North America, eating disorders present a significant public health challenge, with an estimated 10% of young girls affected. Those engaged in aesthetic-focused sports like dance face even greater risks due to intense pressures for a slender physique. Eating disorders in dancers are generally very common. Through data analysis and studies published, sufficient data regarding the percentage and accuracy dancers have of realistically falling into unhealthy disordered eating habits or the development of an eating disorder were extracted. Dancers, in general, have a higher risk of developing eating disorders than the general public, primarily falling into anorexia nervosa and EDNOS. Research has yet to distinguish a direct correlation regarding dancers having a higher risk of developing bulimia nervosa. Studies concluded that dancers overall have a three times higher risk of developing eating disorders, more specifically anorexia nervosa and EDNOS.

Dance on social media
Dance has become a popular form of content across many social media platforms, including TikTok. During 2020, TikTok dances offered the opportunity for isolated individuals to interact and connect with one another through a virtual format. Since its debut in 2017, the app has also attracted a small but growing audience of professional dancers in their early 20s to 30s. While the majority of this demographic is more accustomed to performing onstage, this app introduced a new means to generate professional exposure.

In animals
Some parrots and elephants have been observed dancing in a way that follows the beat of the music. Other animals appear to lack the ability to do this spontaneously, though some can be trained or led by humans.

title: Dance