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Talk:Sexual dimorphism

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Wiki Education Foundation-supported course assignment
This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Peer reviewers: Jenniehorstmann.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 09:05, 17 January 2022 (UTC)

Restored
Thanks for restoring this article. I have added a few examples off the top of my head to be helpful to anyone who checks this article for information. I will add more information later.

Patrick0Moran 15:40, 13 Aug 2003 (UTC)

Concerned
I'm concerned about the following bit.

 * (In grammatically gender-sensititve languages, the grammatical gender of the animal species name besides humans indicates the larger gender of that species. Therefore, the animal species name is grammatically feminine if the female is larger than the male, and vice versa.)

This seems to be too broad. I can think of half a dozen counterexamples in Spanish and Italian off the top of my head. Furthermore it doesn't have much to do with the main thrust of the article. Unless anyone comments, I'll remove it. Theanthrope 20:54, Dec 18, 2004 (UTC)

(In grammatically gender-sensititve languages, the grammatical gender of the animal species name besides humans indicates the larger gender of that species. Therefore, the animal species name is grammatically feminine if the female is larger than the male, and vice versa.) I agree, it's simply irrelevant to the biological article unless it were a fairly reliable guide to relative animal sizes and I agree with you it probably isnt. We'll park the statement here if the original author wants to defend it.alteripse 21:45, 18 Dec 2004 (UTC)

 * I have to agree here. The wording of the phrase indicates that it's an "always" condition.  But considering that "the Cat" = "die Katze" (German, female) = "el Gato" (Spanish, masculine) indicates that it's entirely unreliable.  Of course, there's also the fact that much more reliable in German is that the grammatical gender of the species is determined upon the general size of the animal, rather than any sexual dimorphism in the animal.  Thus, larger animals are masculine, while smaller animals are feminine.  Of course, "larger" and "smaller" here is intentionally vague and subjective, and this "rule" is still by no means reliable enough to use it for anything except where only a wild guess is the other choice. --Puellanivis 18:27, 17 August 2006 (UTC)

The wording of the caption for the picture of the pheasants should be changed to reduce redundancy. I think “large degree of sexual dimorphism between the sexes” should be changed to something like “large degree of sexual dimorphism” or “dramatic difference in form between the sexes”. —Chris Capoccia 18:11, Jun 24, 2005 (UTC)

 * Good suggestion - done! -- ChrisO 18:17, 24 Jun 2005 (UTC)

I think one would have to be socially retarded to not realize that the human on the left is male and the human on the right is female. Sour pickle 04:58, 7 November 2005 (UTC)
 * Maybe so. But the drawing, frankly, isn't that good, and I pity the alien that has to make an identification based upon it. - Nunh-huh 05:02, 7 November 2005 (UTC)
 * Firstly, there's social dimorphism represented in the picture with hair length. Men and women do not naturally have differing hair length.  The drawing could be made better by giving them equal hair length, and the male a beard.  But even in this case, there are women who must shave or they will grow a beard (any woman exposed to enough testosterone will grow a beard, as evidenced in transsexuals), and men can readily grow breasts under the effects of hormones (again, transsexuals can demonstrate this easily.)  But take away even intentional hormone manipulation, there are men who develop breasts (which can be quite large) naturally, it's called Gynecomastia, and there are women who must shave naturally to remove facial hair.
 * To be entirely accurate, sexual dimorphism in humans is very much strictly limited to resulting from hormonal differences, and to a degree much higher than any other species, there is a very low sexual dimorphism. Of course, the key point that you say is "one would have to be socially retarded", which *does* happen.  The gender cues that we interpret are very much not at all accurate indicators of true sex at all.  Super models are taller than the average man, and there are 10% of men that are shorter than the average female.  Many crossdressers can easily demonstrate that it is possible to fool the vast majority of people's sexual indicators, and be regarded or considered as the other gender.
 * Basically, what I'm saying is, don't take a picture that exagerates the differences as an indicator of sexual dimorphism. Take any two pheasants of differing sex and you will readily be able to tell them apart.  The same cannot be done with humans.  There are a number of androgenous males and females, that can make sexual distinction difficult.  To reiterate, that doesn't happen at all with strongly sexually dimorphic animals. --Puellanivis 18:27, 17 August 2006 (UTC)

I'm surprised there isn't a picture of a black widow spider male and female in this article. --AnYoNe! 22:18, 22 January 2007 (UTC)

Your talking about all humans. What I have seen in some races is sexual dimorphism that is extremely pronounced. Indian men in the north of India are much larger and heavier than Indian women. Show me a population of Indian women that are 6'. Most of them are only 5' and slender. So what I'm saying is that sexual dimorphism in humans varies between races. ==Human sex ual dimorphism==

"Homo sapiens has a high level of sexual dimorphism in general." "The low level of sexual dimorphism in humans is said to correlate to the human species' high degree of paternal investment." Methinks this is hard to grok. So what is it? "High level" or "low level"? I have definitely read both views. I think Britannica says social mammals (like humans) generally have high levels of sexual dimorphism, including behavioural dimorphism. I'm a bit suss about the parental investment argument tho, 'cause it's almost circular -- if one parent invests more, voila!, you got sexual dimorphic behaviour already! Can anyone give me a source for each opinion? Then I can go check 'em and make up my own mind. Live long and prosper. V Alastair Haines 11:35, 29 March 2007 (UTC)

 * I don't think high/low in this case is something that can be untimately defined, but it is competely dependent upon what it is compared to. Mikael Häggström 10:49, 15 July 2007 (UTC)

 * I've found a good source on this now. Evolutionary psychologists have done a lot of work on human mate selection including cross-cultural studies of expressed preferences. Paternal investment over evolutionary time should predict current male preferences regarding ideal age of mates. If human males have had low investment, they will have prefered relatively older women (who will look after offspring without them). If investment has been higher, the preference will have been for relatively younger women. The source suggests if the offspring (men now) prefer women in early 20s, it would suggest higher levels of polygyny and higher sexual dimorphism; if men now prefer women in mid teens, this would suggest higher monogamy and lower sexual dimorphism. LOL, that's a rock and a hard place! The source wisely doesn't take sides, just comments opinions are divided. There's a lot more to the analysis than I've mentioned here, and there are literally hundreds of studies. Alastair Haines (talk) 05:16, 17 April 2008 (UTC)

I think the part, that women can withstand cold better then men becouse of more subcutaneous fat should be removed until someone has found a good source for that. Maybe the better insulation is only a compensation, because women baturally have a slimmer body, which leads to a higher surface/volume ratio, which increases the ratio between lost thermal energy and body weight. --Qaywsxedc (talk) 17:48, 21 June 2008 (UTC)

Either the definition of sexual dimorphism at the top of the article is incorrect, or (much more likely I believe) many if not most of the examples mentioned in the Human sexual dimorphism section (gonadal, hormonal differences, etc) are not really sexual dimorphism. Here's one source... http://www.blackwellpublishing.com/ridley/a-z/Sexual_dimorphism.asp that defines sex. dimorph. as "existence of physical differences between the sexes, other than differences in the sex organs." That definition doesn't specify "external" like the current wikipedia does. I would think that external *is* be important if the term is used primarily with regard to Darwinian sexual selection (i.e., I prefer the definition at the top of the page here, although I'm not an expert.)  Is anyone (perhaps with more credential than me on the topic) up for hacking out the stuff that doesn't fit. I think this would also help with the "high" vs. "low" dimorphism question below, settling it on the low side if I'm correct. sbump (talk) 17:55, 6 June 2010 (UTC)

I think there could be a lot more information on differing points that deal with modern views of dimorphism. For example, Christine Gudors research could be added to aid in understanding more. Enteryourcleverusername (talk) 06:33, 24 September 2016 (UTC)

Could we have human dimorphism be a whole separate page? I feel like this information is growing, and could easily be expanded so that it's not just a topic, but it could be a link to its own specific page. Enteryourcleverusername (talk) 06:34, 24 September 2016 (UTC)

The page on Cheistine Gudorf is only available in German, how can we make a page in English so we could direct people looking for more information to her research on the topic? Enteryourcleverusername (talk) 06:35, 24 September 2016 (UTC)

Flyer22 Reborn, in response to your question - I am editing the page for a class assignment. Sorry, I didn't realize the two articles were connected. And I forgot about the sourcing, whoops. I will keep all in mind. Thanks. (whole editing and talking process a bit confusing/daunting) — Preceding unsigned comment added by Enteryourcleverusername (talk • contribs) 21:05, 14 October 2016 (UTC)

What's the problem with evolution?
Under the header Uncertainty, the following is found:

''in birds larger size of males is explained by preference in the struggle for female and larger size of females—by advantage of laying large eggs. But it is unclear why in the first case no large eggs and in the second no struggle for female are needed.''

What is unclear? Both the male and the female are larger than they would have been if it wasn't for the factors mentioned. The difference in size is simply the difference in to which DEGREE the factors are essential. Read The Origin of Species and you'll see that traits are advantageous in a relative sense and not an absolute one, as if there were a standard size which either the male or female deviated from. Mikael Häggström 10:54, 15 July 2007 (UTC)

 * This section is so confused and contradictory that I've taken it out altogether. The deleted text is pasted here:

Uncertainty
Treating the general phenomenon of sexual dimorphism as a consequence of narrow mechanism of sexual selection created many problems. It was hard to explain sexual dimorphism for characters, which with great difficulty can be related to sexual selection (e.g., leaf number and shape, branching pattern in plants). Interpretation of the same phenomenon needed different logics. For example, in birds larger size of males is explained by preference in the struggle for female and larger size of females—by advantage of laying large eggs. But it is unclear why in the first case no large eggs and in the second no struggle for female are needed. It is still difficult for the theory to explain large size of females in some mammals (bats, rabbits, flying squirrels, spotted hyenas, dwarf mongooses, some whales and seals), existence of marked sexual dimorphism in monogamic species with sex ratio 1:1, and the dependence of sexual dimorphism on the reproductive structure of the population.

 * I suspect it's either derived from a general lack of understanding of the whole preceding section, or from Creationist dogma, or perhaps both. I can make neither head nor tail of it in scientific terms, as it deals with issues which are really not controversial.--Richard New Forest 14:57, 29 October 2007 (UTC)

 * There's more than one ideology opposed a priori to biological explanation of sexual dimorphism. Thanks for cleaning things up. Alastair Haines 00:10, 30 October 2007 (UTC)

Textbook like
This headings like "examples", "explaination" etc are textbooklike. But encyclopedia is about "presenting facts", not "teach subject". See WP:NOT. Thanks. Meets are hoped (talk) 06:28, 10 December 2007 (UTC)

There're five images in the article(without counting the one about human's sexual dimorphism) 4 of birds and one of fishes, wouldn't it be okey to add one of insects or mammals, I think we have enough of birds. —Preceding unsigned comment added by 189.175.172.15 (talk) 04:15, 15 April 2008 (UTC)

 * Thanks for comments, feel free to improve the article by rewording or rephrasing ideas. Even better, add in material from books you have access to. If others disagree with you it may disappear, that's just how it works. But it's fair, and most changes, most of the time, mostly lead to improvement and agreement.

 * As a postgrad, Encyclopedias of Philosophy, Theology, Language, History and many subjects are my textbooks. Sometimes they are the fastest way to get simple explanation or a quick set of examples that I'd have to take ages finding elsewhere. Some of them cover all examples and provide comprehensive explanation. I didn't see Wiki is not a textbook on the Wiki-is-not list, but I only scanned a big page.

 * I think this article has a long way to go. It needs way more content, a lot more organization and some improvement in style. Any steps in that direction are welcome, anyone can do it, no one is paid to do it, so it won't happen unless people just get in there and do it. Go for it! Become an expert as you read sources and write them in your own words or quote them into the article.

 * Same goes for pictures. If you own a picture and are willing to donate it, or if you are willing to locate public domain pictures, go for it! Please, please, please. And, speaking just for me, birds are nice, but yeah, I'd like to see a bit more diversity in the graphics. Mind you, dimorphism is the subject isn't it, so we are really looking for pictures of a male and a female with visible differences, frequently (mostly) it's all under the skin or in the head. ;)

 * Happy hunting! ;) Alastair Haines (talk) 11:02, 29 April 2008 (UTC)

explanations for sexual dimorphism
Curiously this article is blocked at my university (can't have us biology postgraduates reading any article about sex), but checking this for the first time outside of uni I notice that it is missing niche separation as a cause of sexual dimorphism. At least in birds it is the more important cause of size differences. for an example (lots more come up on on google scholar). Sabine's Sunbird  talk  20:08, 14 July 2008 (UTC)

That's also getting on my nerves. There's a lot of focus on passerines and game bird sex dimorphism, but very little on the fairly dramatic dimorphism birds of prey have. Falcons often have size skewed towards females, with many being a 1/3 larger than their mates. Generally, it's more so that females can take larger prey and the males smaller so that one prey group isn't too heavily hunted. That section could really use expansion, and be less general. —Preceding unsigned comment added by 71.239.162.195 (talk) 04:37, 7 February 2010 (UTC)

Sexual size dimorphism
I noticed this more specific article a couple of days ago, but is there really any need for it? This article isn't excessively long, and SSD is excessively short. It has some potential, but it has been poorly integrated into the network of articles - for example this article should obviously link to it (probably using summary style) and it should link back here (which it doesn't). Unless there is so much on SSD that it makes this article too long or biased towards size differences, I think the best option is to merge it here. Richard001 (talk) 22:28, 8 October 2008 (UTC)

 * Yes – can't see how we could justify a separate article at present. Richard New Forest (talk) 08:38, 9 October 2008 (UTC)

 * The article's author hasn't been editing for over a year, so we can't really get any comment from that quarter. There isn't much to incorporate, though we should include the term 'sexual size dimorphism' and the abbreviation in the article somewhere. A pity the article has no references for the other statements, though I guess they could be added as well. Richard001 (talk) 07:20, 10 October 2008 (UTC)

Sexual dimorphism in humans
Men are 34% stronger in the lower body. Source: http://www.ncbi.nlm.nih.gov/pubmed/8477683 Someone please correct it. --- dnx-x1 —Preceding unsigned comment added by Dnx-x1 (talk • contribs) 21:44, 12 November 2008 (UTC)

In a control group of 8 men and 8 women. How robust. —Preceding unsigned comment added by Akaner (talk • contribs) 17:20, 13 October 2009 (UTC)

 * Yes, correct it to reflect how males have been having a free ride the whole time. Natural truth isn't allowed to interfere with academic knowledge. —Preceding unsigned comment added by 74.13.44.121 (talk) 05:11, 31 August 2010 (UTC)

Text in the anglerfish picture
It says that the male anglerfish is a parsite. The definition of parasite:Parasite states that the victim has only harm, but in this case, the "victim" has unlimited amounts of semen for the eggs. Therefore, the male anglerfish isn't a parsite, they're living in symbiosis. Someone correct the picture and reupp it. —Preceding unsigned comment added by 213.250.11.107 (talk) 15:28, 17 August 2009 (UTC)

 * They also call it a parasite in the text. I see how it is similar to a parasite, but in reality that is a specific word with a specific meaning that is not correct in this situation. 207.61.204.116 (talk) 00:43, 28 November 2013 (UTC)

Handicap
"the proposed evolutionary force" is totally overstated. Though popular, the handicap principle (actually, "handicap hypothesis" is becoming more popular among scientists in recent years) seems to apply in far fewer cases than generally assumed. For peacocks, I think it has never been proven (given they are Phasianidae, among which some sort of ornamental plumage is widespread, an "unhandicapped" male would have zero fitness!). As typical of mid-20th century ethology, this is just another "intuitive" explanation with meager empirical support.

There are probably almost as many causes as there are different sorts of sexual dimporphism, dichromatism, size dimorphism etc. Reverse size dimorphism in predatory birds is simply competition-avoidance (this has been extensively proven). Dysmorodrepanis (talk) 00:54, 29 October 2009 (UTC)

 * I've rewritten the evolution section to present what textbooks seem to say. Evercat (talk) 19:44, 21 January 2010 (UTC)

New study finds "Sexual Dimorphism" between heterosexuals and homosexuals.
From the article: ''Pheromonal studies also have added to the scientific knowledge of sexuality, according to Dr. Goldstein. "Sex-atypical connections were found among homosexual participants. Amygdala connectivity differences were found to be statistically significant and provided evidence towards sexual dimorphism between heterosexual and homosexual subjects. "'' I am confused by this usage of the phrase "sexual dimorphism". Does this suggest that the meaning can be extended to members of the same gender who have different sexual preferences? If so, should wikipedia reflect that? 97.94.199.170 (talk) 16:04, 4 June 2011 (UTC)

Race and Sexual dimorphism
I'm concerned about including the anecdotes of someone who specializes in insects on human sexual dimorphism. As there really isn't a genetic basis for the differentiation of race, the unsubstantiated comments in the "Race and sexual dimorphism" section come off more as hearsay than actual fact. It contains outdated terminology, and half of the section gets its information from the opinions of an unqualified expert. I think the section should just be deleted. — Preceding unsigned comment added by 99.191.40.174 (talk) 09:10, 15 September 2011 (UTC)
 * That does not explain why you removed the citation to Ashley Montagu who taught anthropology at Princeton University. The citation was cited to a reliable source -- an expert speaking within his field of study. --Ephert (talk) 09:16, 15 September 2011 (UTC)

sexual dimorphism is a very understood part of living creatures differences. Yet in human evolvement of the thinking mind it becomes less inclined to provide basic evaluations of whats to be concrete and unquestionable while human thought has provided outlets to creative dimorphism within intellectual creativity and human inclinations.Maybe earlier hominids were more in tune to earthly survivals through instinctual strenght. While modern mans social and earth shattering thinking mind has reigned dominance.Is the crossbreeding of humans with differing skin color or facial details a change from mono polydimorphism within a group that maintains its genetic pool and suddenly that new divergence now extends gene pool diversity within the offspring.Since homo sapiens sapiens are all thinking oriented people regardless of the genetic variances within our appearances due to our inheriting the genes from our parents now creating a new gene pool of traits passed from each others ancestors. Are all humans evolved from a common ancestor or from divergent ones that have survived but evolved to distinguish the gene pool we have. Basically the human mind trancends the simple mental state of their nature that primitive man or woman encompassed but with a strong will to survive. — Preceding unsigned comment added by Nabjeski (talk • contribs) 00:42, 27 October 2011 (UTC)

'American English'? 'British English'? Some other language?
"Dichromatism is where a sex of a given species is more than one color including that of saturated, vibrant hues."

For the life of me I can't work out what the author of that sentence was trying to convey. Also, it (Dichromatism) seems to have no logical connection to the preceding sentences, the paragraph, or the article.

Aaah. Such is Wikipedia... — Preceding unsigned comment added by 86.160.209.12 (talk) 20:42, 15 December 2011 (UTC)

Women's running times are not 11 percent faster than males. Where did they get that information from the citation displayed.?
someone fix this badly written article. — Preceding unsigned comment added by 68.106.44.60 (talk) 16:19, 20 May 2012 (UTC)
 * I've corrected the article's wrong conclusion and provided more appropriate language for referring to a single study. You are encouraged to be bold and edit the article yourself! - Rushyo  Talk  16:26, 20 May 2012 (UTC)

Anisogamy and evolution in dimorphism
In the evolution section, someone posted a statement more or less to the effect that anisogamy was the basis of, or otherwise relevant to, sexual dimorphism. I was about to revert it, but decided that it would be better to refute it in case it emerged again. I stuck in a few refs and links in support. (Just mentioning this in case you thought it was my idea!) JonRichfield (talk) 08:04, 29 May 2012 (UTC)

I have no idea why you want to revert it. Anisogamy itself is a sex dimorphism. I was wandering why no body even bothered mentioning it. When you talk about evolution, do NOT forget that evolution is a history and that evolution is built upon previous evolution. Yjiangnan (talk) 17:43, 29 May 2012 (UTC)

Please note that I did explain that Anisogamy is not a sexual dimorphism because, just for example:
 * 1: The gametes do not in general have anything to do with gender, unless they are from a species in which they bear sex-determining genes. (Consider many reptiles, molluscs, and fishes for example. Have fun with Monotremata!)
 * 2: Even in spp with sex chromosomes, it is the zygote that has the gender, not the sperm or the ovum.
 * 3: Even when there is a sex chromosome and it determines gender, it does not follow that the gamete (whether egg or sperm) that determines the gender that corresponds to the larger and more impressive or more competitive gender (not always the same thing!) of adult comes from the more numerous gametes.

Also note that the arguments based on the observations concerning sperm competition have no logical connection to sexual dimorphism in the adults in general. If you think that sperm competition is of importance or interest (with which I agree) then please deal with it in articles where the points are relevant. JonRichfield (talk) 19:05, 29 May 2012 (UTC)

I do not think you are arguing in a logic way. By definition, sex dimorphism is "a phenotypic difference between males and females of the same species". Of course, sperm and eggs are different. Males have sperm and females have eggs. Gamete size difference is a real difference between males and females, and there is no way to argue against this simple fact. If you do not agree with this, it just means that the definition of sexual dimorphism in your mind is too narrow. I am not sure what you mean by saying that sperm and ova do not have gender, but males are defined by producing sperm and females are defined by producing eggs. By the way, gender is not a very scientific term to refer to the biology of sex or sex dimorphism.

So, unless you are going to change the definition of sex dimorphism, I will insist on placing my edit here.

Regarding to your last paragraph, I am afraid that few things have "logical connection to sexual dimorphism" "in general", but I am not seeing you removing all of them. Sperm competition have fairly strong connection to sexual dimorphism (both logically and evolutionarily), and it will be wrong to not mention it. Additionally, what I add here is well accepted by many people in the scientific community. If you have different ideas, you can of course make your points. But it is improper to prevent others from expressing their ideas. I need to remind you that you need to keep neutral in Wikipedia. Yjiangnan (talk) 23:32, 29 May 2012 (UTC)

Thank you for your contributions on my views. A couple of points.
 * 1: You are helpful in supplying a definition of sexual dimorphism; if ever I need it, I shall be sure to request it from you. You said: "Anisogamy itself is a sex dimorphism", which plainly is nonsense. The dimorphism is in the gonads, not the gametes. You also say: "Of course, sperm and eggs are different." Of course indeed. However, that does not mean that sperms and ova have genders. Next time you see a male sperm or a female ovum that differs phenotypically from a female sperm or a male ovum respectively, or for that matter, a species in which all the sperms are male and all the ova female (or vice versa) I trust that you will document this remarkable phenomenon. Until then, the idea of sexual dimorphism between gametes involves a confusion of concepts and misapplication of terms.
 * 2: OTOH, as you are assuming that anisogamy is an instance of sexual dimorphism, perhaps you should merge the anisogamy page into Sexual dimorphism. In the interests of your personal popularity on WP however, it might be better first to demonstrate that you have an instance where the anisogamy constitutes an instance of (ahem) "a phenotypic difference between males and females of the same species". You first would have to demonstrate that gametes produced by males are male and gametes produced by females are female (or perhaps vice versa).
 * 3: You are too generous with your advice on science and scientific terminology. Spare me your concept of a "very scientific term" (or not very, as the case may be). Proper use of the word "scientific" is not as easy as it seems; to the extent that it applies in this connection at all, it applies to concepts rather than terms, or at the very least to the use of terms in reference to concepts. The relevant principle is the usefulness of the term in question. Maybe you would do well to learn the proper use of "gender" in science as well as some other connections. The term "sex" and its derivatives carry a great deal of baggage that leads to ambiguity; the term "gender" in this sense deals with the abstract discrimination between masculine, feminine, neuter and the like. That is why in linguistics one does not speak of English, French, and German for example, having one, two or three "sexes", but "genders". Where I used the term "gender" in reference to organisms and gametes, as I invite you to inspect, you will find that I invariably referred to the discrimination, where for example, questions of copulation and the like did not arise. You say: "I am not sure what you mean by saying that sperm and ova do not have gender..." I am sorry if you missed the significance. Better luck next time. Try saying "I am not sure what you mean by saying that sperm and ova do not have sex..." and see how that makes it clearer. If it does, then please tell us all how to tell the little boy ova in a bunny from the little girl ova, and the little boy sperms in a sparrow from the little girl sperms. Until you can do that, I don't know how you can have any idea of what it would mean to claim that sperms and ova have either gender or sex. If still in doubt, you might find it helpful to read the WP article on Gender.
 * 4: You generously explain that "Of course, sperm and eggs are different. Males have sperm and females have eggs." A curious statement, as I am sure you will see on reflection. What you have described is a difference between males and females. Your statement also suggests that if I see a gamete, I should first ask what what begot it before I can refer to it as sperm or ovum. You are well aware that dimorphism means difference of form, I am sure, not difference of parentage. You could have saved your keystrokes anyway. I already realised that sperm are not ova, and a good deal more that you should reflect on.
 * 5: You say that "the definition of sexual dimorphism in your mind is too narrow". How narrow is "too" narrow? If the very fact that an organism has an ovary rather than a testis is to be regarded as primarily a concern of sexual dimorphism, then what is 'not' sexual dimorphism? If you distort the concept of sexual dimorphism to include every single gender-associated difference, then you might as well lump every biological topic from Aspergillus up, into the study of sexual dimorphism. By stretching the definition to such an extent, you reduce it to meaninglessness. Please note that the significance of a term is just as much in what it excludes as what it includes. If it excludes nothing, the term is useless. Have you heard the expression "the tail wagging the dog"? That is why we have topics such as "Anisogamy". If you wish to link to "Anisogamy", I can only applaud, but if you wish to subsume anisogamy under sexual dimorphism there is a problem. Narrow or not, I hope you can see that.
 * 6: You say that sperm competition has "fairly strong connection to sexual dimorphism (both logically and evolutionarily), and it will be wrong to not mention it." Of course it would, but as it stands the mention is incoherent, inconsistent and largely in the wrong place and in several respects just wrong. Sexual dimorphism is just one theme in a large matter, which is a lot more complex than you seem to suggest. As a topic, it would belong in Evolution of sexual reproduction, with no more than a mention and a link in Sexual dimorphism. With that task I would be happy to help if required, or stay out of it if not.
 * 7: You say: "Additionally, what I add here is well accepted by many people in the scientific community." It is not enough to state facts; they need to be stated properly, coherently and in proper context. And in saying that I am being charitable about much af what you stated as fact. Most of what you say is at best debatable in context and this is not intended to be a debate, but a correction. Furthermore, it is not honest of you to suggest that you are being muzzled. If it is "improper to prevent others from expressing their ideas", then bear in mind that I too am an "other" and you have now twice reverted my corrections. Who is calling the kettle black? You have no more exclusive right to the medium than anyone else, and no less responsibility to keep neutral.

Now look. You have twice reverted my corrections. I shall not at this point get nasty and threaten WP sanctions and all that. Nor shall I as yet go to RFCs, DRs and all that stuff. You have some views on matters of fact and some on matters of opinion. What I see in the article at the moment is not to my mind acceptable in WP. However the material is of importance and with some editing, amplification, and publishing in the right context in other WP articles (plus links etc of course) we could mend matters outside the article (here if you like). How do you feel about that as a proposal? Or can you suggest alternatives? JonRichfield (talk) 12:04, 30 May 2012 (UTC)

Well, I see your potential to complicate a simple logic into a hardly communicable way. "Sexual dimorphism is a phenotypic difference between males and females of the same species." This is not just my definition, but a definition at the beginning of the page of sexual dimorphism." Phenotypic difference" means any difference between individuals that is caused by the combined effects of both genetics and environment. Consider a zygote that develops into a male and another zygote that develops into a female. Then, males produce sperm and females produce ova. So, productions of sperm and ova are phenotypes that are controlled by the genes of the two zygotes. People use "phenotype" usually to compare with "genotype". Phenotype can mean anything from shape, color, behavior, and of course, the size of gametes. So, by definition, gamete size difference (anisogamy) is one phenotypic different between males and females, and is one instance of sexual dimorphism. It is also an important instance of sexual dimorphism, since it is the fundamental difference between males and females, otherwise you will never be able to define what is a male and what is a female in the huge diversity of life on earth. It also has important evolutionary connections with other instances of sexual dimorphism. That is why I think it deserves a few sentences here. Later in the section, it is mentioned that "In many non-monogamous species, the benefit to a male's reproductive fitness of mating with multiple females is large, whereas the benefit to a female's reproductive fitness of mating with multiple males is small or non-existent". If you are really familiar with the scientific literature of sex evolution, you will know that this is actually exactly the conclusion of sperm competition. Previous editors simply failed to point this out.

Sex has relative clear meanings in biology. Biologists usually use "sex" rather than "gender". That is why this page is called "sexual dimorphism" rather than "gender dimorphism". "Gender dimorphism" is too narrow, while sex is a more general term.

By the way, I only reverted you your reversion once, not twice (the other time I just re-edited what I think as improper in your edition). Mine is difference from yours because you reverted something I put a lot of work in but I only revert your few mouse clicks. You did not feel it maybe because you have more spare time to spend in Wikipedia than me so you did not think that my writing a paragraph is a lot of work. However, as a biologist who has a lot of research to do, I really do not have so much time here or arguing with you. I tried to edit this page simply because I do not think this page is complete enough for what biologists understand as sexual dimorphism. So, maybe I will not continue arguing with you here. But if you still think my addition has problems, I hope you can open your mind and give it a second thought. You may re-edited it to make it coherent with other stuffs, but I will feel uncomfortable if you simply revert it or delete many of my sentences.

Or, maybe it is better to settle it another way. We leave it in its current form, and let others re-edit it if they also feel it improper. Then the bias of yours and mine can be reduced. Yjiangnan (talk) 17:24, 30 May 2012 (UTC)

 * Sorry; been otherwise occupied; you are not feeling neglected, I hope. You say: 'Well, I see your potential to complicate a simple logic into a hardly communicable way. "Sexual dimorphism is a phenotypic difference between males and females of the same species."'

 * Thank you for the compliment, but a lot of people seem to be unable to distinguish between simplicity and simplistic logic. Permit me to assist. It is dangerous to use formal logic uncritically in dealing with empirical considerations. Formal logic tends to deal with variables and assumptions that can have meaning only relative to restricted sets of values and relationships. Empirical topics are far less restricted. Consider your dictionary definition and explanation of phenotypic differences. (You say it is not "yours", but what difference does that make? Are you using it under duress?)

 * You could in any case have saved your keystrokes; I don't know about your academic institutions, but round here that isn't even genetics or cytology 101; it is schoolwork. And thereby hangs a tale. You see, the schoolkids tend to get the simplistic version, much the sort of thing that Johannsen coined the term phaenotypus for  over a century ago. But you see, in Johannsen's day there was hardly any idea of what a gene was, or how it worked, so there was no difficulty separating genotype and phenotype as in formal logic.  Since then some of us have progressed further and nowadays the concept of phenotype as opposed to genotype, instead of becoming more distinct, has become fuzzier since we began to understand something of their relevance to each other. (I hope!) So has the concept of an "individual", unless you happen to be a fan of Strawson (which I never have been, but suit yourself).  For example, I doubt that Strawson would have made much sense of Lynn Margulis' work. We not only can see actual genes in some kinds of actual chromosomes, we can determine their actual chemical configuration as well. Are you going to claim that material that we can determine empirically, such as the actual physical constitution of the genetic material of an organism, is non-phenotypic? (Remember that before we ever had electron micrographs, we already had plenty of images of bands on polytene chromosomes!) And if you will (very sensibly) accept that our ability to view chromatin directly makes it hard to cleanly separate genotype from phenotype, then what about epigenetic observation? Is methylation status phenotype or genotype?

 * So please don't blame me if simplistic assumptions get you into trouble. Facts in biology (and science in general) are to be assessed on their own terms, not crammed into forms to suit your preconceptions. You said: "People use "phenotype" usually to compare with "genotype". Those who know what they are talking about, use the words as terms of convenience, not fundamental concepts, and they have not really done so since about WWII. I use the terms myself, but where they are no longer applicable, I use more direct terminology. What is more, where they apply to one aspect of a matter, I do not accept that they must apply to another. For example if you insist that the difference between ovaries and testes is a phenotypic difference, I say: so what else is new? If you insist that the difference between sperm and ovum is phenotypic, I say very likely, but be careful, because my bs meter is vibrating. If you say that therefore you can assign a gender to every sperm and to every ovum, I say tell it to the New Agers. Trivially gender might be a consequence of environment and genetics, but it does not follow that as soon as you have environment and genetics, you have gender. (Right? What was that again about logic?)  And that is without your difficulties if you deal with hermaphrodytes and haploid generations.

 * You say, in part: "...otherwise you will never be able to define what is a male and what is a female in the huge diversity of life on earth". Sure, but so what? Who said you need to? What is there about gender that makes it indispensible? For probably at least two (maybe three, don't call me a liar if I guess wrongly; I wasn't there) billion years life on this planet got by without gender (unless you know better of course!) To this day we have plenty of organisms that have no gender, or have both genders, or first one than another gender.

 * Oh, I almost forgot; gender is unscientific, isn't it? Tsk tsk! You must explain that someday when we have time. Let's see… "Biologists usually use "sex" rather than "gender"." Really? I propose that that depends on their degree of literacy. I have never had a biologist rebuke me for being unscientific because I spoke of gender. You say: 'That is why this page is called "sexual dimorphism" rather than "gender dimorphism". "Gender dimorphism" is too narrow, while sex is a more general term.' Hmm? And: "too narrow"? How narrow is too narrow? In what way is it too narrow? A definition is a definition; where one has a sharply defined concept you want a sharply defined term, when the concept is broader you want a broader term. You seem to be very free with your use of the word "science" and its derivations; better check on its meaning before you trip yourself up again. You say: "...clear meanings in biology"? What is unclear to you about "gender", in biology or out? In how many examples where I have used the word "gender" would you have improved the sense or logic by substituting "sex"? This is a good opportunity for you to put up or shut up when talking about being scientific, I should think. I'll be watching in anticipation!

 * For an example of what I assume you to regard as a scientific statement; "So, by definition, gamete size difference (anisogamy) is one phenotypic different between males and females, and is one instance of sexual dimorphism." That is simple and simplistic nonsense. The phenotypic difference (temporary or permanent) is in the gonads, it is not in the gametes. (Repeat that over to yourself a few times; gonad, gamete, gonad, gamete – it shouldn't be too hard; you are after all a biologist, right?) Do you think that you could show me a male sperm? Or a male ovum? Or do you suppose that all sperms are males and all ova females? Tell that to the turtles and the Tenthredinidae, if you do.

 * OK, let's assume that you now can tell the difference between anisogamy and anisogony (don't bother looking it up; I just coined the term – scientifically (and it is wrrong!)) What I mean by anisogony is that the two genders have different gonads. That is certainly a difference. Whereas you have no way in general of defining the sex of a gamete, and you have repeatedly denied that you understood what I meant by saying it.

 * Now, I hear you cry, I am contradicting myself by saying that the genders are different. But there was no contradiction. If you want to speak about being scientific, you need to be objective, you know! Certainly the genders are different and vive la difference! But then all you have come down to is that males are males and females are females. (Not always of course, but close enough for jazz.)

 * This difference is important, I agree. But it also is tautological. It tells us nothing of interest. The main study of sexual dimorphism deals with other types of difference, and almost exclusively secondary sexual characters. I agree that this too is not cleanly definable. I accept that in most organisms an ovary suggests a female gender, and a uterus in nearly as many, and female external genitalia, all of them as primary sexual characters if you insist. But then, how about functional mammae? They generally are seen as secondary, which I must say always bothered me, but OK. And the peacock's plumage? Definitely secondary, right? Etc etc. None the less, if you charged into a conference where sexual dimorphism is under discussion and shouted: "Hey guys! Big news! All that secondary sexual stuff is minor; you should be looking at the primary sexual characters." You would get a dusty reception. See whether you can work out why.

 * But, you say, all successful sperm competition relies on sexual dimorphism as a class of evolutionary strategy, and vice versa (which is garbage, but never mind that now). Suppose it does. It still isn't the primary topic of sexual dimorphism. It is a major topic of anisogamy. (Which has its own article(s)). Do the articles have anything to do with each other? Certainly. So much so that it makes sense to have links between the articles. No problem. But the text that you have insisted on inserting into "Sexual dimorphism" is at once incoherent and non-cogent. The generalisations you make are shocking. In my attempt to keep your material in the article, I offered to cooperate in editing it. You don't seem to like the idea. Are you nervous that I might over-persuade you?

 * OK, here is an exercise for you. After all it is only a paragraph or two. Privately list your statements in that text (the blunders aren't all yours, after all; that whole section needs attention.) And ask yourself which ones I have found to be objectionable, and how you could render them immune from my sniping.  If you do a halfway good enough job on them, I won't be back. Promise!

 * Cheers. JonRichfield (talk) 18:51, 2 June 2012 (UTC)

This article doesn't discuss sexual dimorphism of primary sex characteristics in most species
This omission is surprising, considering that this is one of the most obvious forms of sexual dimorpism in many species. Jarble (talk) 20:59, 18 May 2013 (UTC)
 * The article can't discuss sexual dimorphism in every species there is or in most species, just as most Wikipedia articles can't discuss a topic in every species there is or in most species, without the article becoming gigantic. There is also the matter that most things are not studied in every species there is. We give examples, as you should know by now. Flyer22 (talk) 21:11, 18 May 2013 (UTC)
 * I had thought about the fact that you may mean "discuss the matter that primary sex characteristics is a form of sexual dimorphism in most species." Flyer22 (talk) 22:17, 2 July 2013 (UTC)
 * I've removed the hatnote that I added previously, since it would be redundant to add this information. Jarble (talk) 22:50, 12 October 2013 (UTC)
 * What are you talking about? You added a "missing information" tag to this article, and it's still there. I removed the merged tag you added, documented here and here. Flyer22 (talk) 23:15, 12 October 2013 (UTC)

Arthropods
This article's got sections on plants, fish, herptiles, birds and mammals, IMO it could use a section covering sexual dimorphism in arthropods. -- Gordon Ecker, WikiSloth (talk) 02:11, 31 July 2013 (UTC)

Section on SD in Humans drifts off
I am curious as to why under the section dedicated to sexual dimorphism drifts to discussing birds and general topics not directly pertaining specifically to humans. These bits towards the end are interesting, and I would assume correct, but they don't seem to belong in this location. At the same time I am not really qualified on the topic at large to properly move this information to a different more correct location.--MDVang (talk) 11:30, 11 November 2013 (UTC)

Human Dimorphisism Image
Can this be replaced? The current image is eurocentric, displays sex dimorphism through unnatural differences like hair length, and is clearly tainted by social bias, i.e the male is standing in a more direct pose, whilst the female isn't even standing up straight. If possible, it really should be replaced by a more scientific diagram. — Preceding unsigned comment added by 86.28.194.198 (talk) 09:06, 13 June 2014 (UTC)

Dimorphisms due to intra- vs. inter-sexual selection
Intra- vs. inter-sexual selection tends to produce different types of sexually dimorphic adaptations. This article really should have a couple of subsections on these topics. Memills (talk) 04:16, 30 July 2014 (UTC)

"Females are taller, on average, than males in early adolescence, but males, on average, surpass them in height in later adolescence and adulthood"
source of info? — Preceding unsigned comment added by 92.234.46.137 (talk) 20:13, 21 September 2014 (UTC)

Bird section thoughts.
I had some concerns with this section and the facts presented and some that were not mentioned at all. 1.) There still can be a dimorphism and equal parental contributions from both sexes. Although males do not produce eggs many stay and provide food while the females protect the offspring. The statement made only provided the extremes of sexually dimorphic males either providing no contribution or all contributions after reproduction. 2.) The topic of monogamous relationships between the birds was not mentioned. 3.) Also not all phenotypes correlate to fitness and there is a type of female selection called runaway sexual selection that is solely due to the female preference of the males and produces a positive feedback for this preferred trait. Willis.421 (talk) 18:28, 30 September 2014 (UTC)

Adult human height/weight differences
Currently, the article claims In the United States, adult males are, on average, 4% taller and 8% heavier than adult females. and references in support.
 * 1) National Health Statistics Reports
 * 2) United States National Health and Nutrition Examination Survey, 1999–2002

I don't see how the sources support the claim. The figures given there for adults 20 years and over are: I.e., American males are on average 8.5% taller and 16%–18% heavier than females.
 * 1) females 74.7 kg (p. 7) / 162.2 cm (p. 13), males 88.3 kg (p. 9) / 176.3 cm (p. 15)
 * 2) females 74.0 kg (p. 9) / 162.0 cm (p. 11), males 86.1 kg (p. 9) / 175.8 cm (p. 11)

—Naddy (talk) 21:32, 16 June 2015 (UTC)

spiders and sexual cannibalism review
I thought that you did a good job explaining that sexual size dimorphism in spiders directly relates to sexual cannibalism as well. I thought you did a good job concisely explaining that larger females are selected due to being more fecund, and that males tend to mate with larger females because they are less likely to cannibalize the male. I added the sentence, “All Argiope species, including Argiope bruennichi, use this method.” In addition, I also thought you did a good job not summarizing any individual studies. Lastly, I changed “is more prominent” to “is more prominently selected for”. Great work! Leflame123 (talk) 02:23, 23 November 2015 (UTC) Leflame123

Sourcing and response to latest human sexual dimorphism query
Enteryourcleverusername, this bit you added needs sourcing. As for what you stated in the section above, keep in mind that, as noted as Talk page guidelines, old sections are commonly overlooked. It's often best to start a new section for a new query. As for creating a Human sexual dimorphism article, we already have a Sex differences in humans article. Flyer22 Reborn (talk) 06:27, 25 September 2016 (UTC)

And, Enteryourcleverusername, "Human sexual dimorphism" redirects to Sex differences in human physiology. So, right now, the Sex differences in human physiology article is the Human sexual dimorphism article. Flyer22 Reborn (talk) 06:31, 25 September 2016 (UTC)

Geodakyan's evolutionary theory of sex
Help required with Geodakyan's evolutionary theory of sex: the article of apparently fringe theory is based almost exclusively on primary sources and edited by a people with strong connection to the subject. Staszek Lem (talk) 17:21, 13 October 2016 (UTC)

Evaluating articles and sources
Overall, this article uses reliable sources that are up to date and unbiased. The references provide information on a wide variety of living organisms ranging from plants to mammals. The factual claims on sexual dimorphism in different species are heavily supported by over 100 references. Also, the lead paragraph is a good example of concise summary of the topic discussed. However, the section on physiological differentiation is a topic that is underrepresented. To improve this section, a definition of physiological differentiation would be helpful, as well as more examples of this phenomenon in nature. The evolution of sexual dimorphism is one other area that is underrepresented. However, another benefit to this article are the vast amount of pictures which provide visual examples of the variability of sexual dimorphism exhibited across species.––Jenniehorstmann (talk) 20:48, 30 January 2017 (UTC)

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Pain tolerance and Sexual Dimorphism
"On average, males have larger hearts, 10 percent higher red blood cell count, higher hemoglobin, hence greater oxygen-carrying capacity. They also have higher circulating clotting factors (vitamin K, prothrombin and platelets). These differences lead to faster healing of wounds and higher peripheral pain tolerance."

This part quoted above on human sexual dimorphism relies on a very old textbook as proof. I request evidence from the last 20-25 years as a lot of work has been done in that time. My main issue however are the conclusions drawn about men having a higher tolerance. EVERYONE knows that people's tolerance to pain can also be severely influenced by how they have been socialised. Men all over are socialised not to cry, put their big boy pants on, taught to see pain as a feminine weakness. Therefore it stands to reason that men seeming to have a higher pain tolerance could be greatly impacted by nurture not nature and might not be as conclusive a dimorphic feature as represented above between cis gendered people.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3690315/ 85.255.233.197 (talk) 01:03, 14 April 2021 (UTC)

 * Please respect non-American users of English Wikipedia and keep your social justice struggles out of the article. Thank you. 78.139.95.32 (talk) 21:58, 10 May 2021 (UTC)

File:Colias dimera copulating.jpg scheduled for POTD
Hello! This is to let editors know that the featured picture File:Colias dimera copulating.jpg, which is used in this article, has been selected as the English Wikipedia's picture of the day (POTD) for June 7, 2021. A preview of the POTD is displayed below and can be edited at Template:POTD/2021-06-07. For the greater benefit of readers, any potential improvements or maintenance that could benefit the quality of this article should be done before its scheduled appearance on the Main Page. If you have any concerns, please place a message at Wikipedia talk:Picture of the day. Thank you! Cwmhiraeth (talk) 10:10, 13 May 2021 (UTC)

What is a non-avian reptile?
As repiles and avians are two separate and distinct things, except for being chordates. The term non-avian reptile is equivalent to reptile. Just like non-reptilian mammal is just a mammal. 68.118.187.196 (talk) 21:18, 3 July 2021 (UTC)

The audio needs an update
The audio for this article seriously needs an update.CycoMa (talk) 19:54, 18 August 2021 (UTC)

Amazing example that could be included on this page
Just a random suggestion as I pass through. This is a great New York Times article about a leaf-mimic insect that is so strikingly dimorphic that it was long thought to be two different species—for one of which only females had been observed—and one only males:

He Was a Stick, She Was a Leaf; Together They Made History

BananaSlug (talk) 17:20, 2 October 2021 (UTC)

Sexual dimorphism and humans
This article is on sexual dimorphism: "di" as in divergent, and "morphism" as in morphology (shape or form). It has always been my understanding that the differences in reproductive organs are not considered as characters in sexual dimorphism. Under the heading Humans, subjects such as metabolic rates, blood cells, granulocytes, antibodies, psychological tolerance to pain, the brain, testosterone, estrogen, genes, and chromosomes are discussed in some detail. Sexual dimorphism does not include ALL differences between males and females. I believe it is only about the physical shape, form, or morphology, the appearance,. I am not the ultimate arbiter on the subject, and I'm not questioning the accuracy of the content, but most of the content under the heading of humans seems off the subject to me.WiLaFa (talk) 03:49, 18 November 2022 (UTC)

COI citespam?
Can you tell me about this edit you made? I don't understand how it is COI or citespam. thanks! UtherSRG (talk) 15:54, 12 December 2022 (UTC)

 * The cite was added by the author of the paper. It doesn't support any content, it was purely redundant with existing citations. They've been doing the same thing on a bunch of other articles. MrOllie (talk) 16:07, 12 December 2022 (UTC)

I see you made a similar deletion for the same reason at Physical therapy. Please provide evidence for your claims of a COI and the exact diffs (plural) for the additions of the content in both articles. -- Valjean (talk) (PING me) 19:47, 12 December 2022 (UTC)

 * Lindenfors: COI confirmedself-cite Pascoe: self cite MrOllie (talk) 20:22, 12 December 2022 (UTC)
 * Thanks. Keep up the good work. 👍 Valjean (talk) (PING me) 20:30, 12 December 2022 (UTC)

I don't get it? Is peer reviewed science really "COI citespam"? So you have these PhD. professors who have been publishing on their field of expertise in international, peer reviewed science journals for 25 years, and these are the people we don't want contributing to Wikipedia? It is not considered a conflict of interest to cite your own publications in peer reviewed journals. People have been doing it for 200 years.WiLaFa (talk) 22:03, 12 December 2022 (UTC)

 * It is a real problem these days. Research has shown that being cited on Wikipedia leads to other citations, so people sometimes do this to pump up their h-index. It is common enough that we have had a standard template warning for this for some time (Uw-refspam). It absolutely is a conflict of interest to cite your own publications in peer reviewed journals on Wikipedia, the guidelines are clear on that. - MrOllie (talk) 22:07, 12 December 2022 (UTC)
 * It is not considered a conflict of interest to cite your own publications in peer reviewed journals. People have been doing it for 200 years.
 * Jane Goodall cited herself here and it did not seem to be a problem with the editors of Nature.
 * Whiten, A., Goodall, J., McGrew, W.C., Nishida, T., Reynolds, V., Sugiyama, Y., Tutin, C.E., Wrangham, R.W. and Boesch, C., 1999. Cultures in chimpanzees. Nature, 399(6737): 682-685.
 * E. O. Wilson cited himself 3 times here and it did not seem to be a problem with the editors of The Quarterly Review of Biology
 * Wilson, D.S. and Wilson, E.O., 2007. Rethinking the theoretical foundation of sociobiology. The Quarterly Review of Biology, 82(4): 327-348.
 * Is there something specifically controversial or problematic about Lindenfors or Pascoe? WiLaFa (talk) 23:26, 12 December 2022 (UTC)
 * Wikipedia is a distinct project with different policies and community standards than what you might find in academic publishing. Not everything that is acceptable in that world will be acceptable in this one. But at any rate, if you want to change the guidelines on this, the place to make that argument is on the talk pages of those guidelines, not on my user talk page. MrOllie (talk) 23:29, 12 December 2022 (UTC)
 * Is there something specifically controversial or problematic about Lindenfors or Pascoe? WiLaFa (talk) 23:26, 12 December 2022 (UTC)
 * Wikipedia is a distinct project with different policies and community standards than what you might find in academic publishing. Not everything that is acceptable in that world will be acceptable in this one. But at any rate, if you want to change the guidelines on this, the place to make that argument is on the talk pages of those guidelines, not on my user talk page. MrOllie (talk) 23:29, 12 December 2022 (UTC)

At Wikipedia, it is NOT true that "It is not considered a conflict of interest to cite your own publications in peer reviewed journals." It is a clear violation of WP:COI to do so.

OTOH, it is okay to use the talk page to suggest one's own publication as a source. Then other editors can add it if they deem the source appropriate to use. This is standard practice. We have banned a Nobel Prize laureate for refusing to back down on this issue, so we take this very seriously. -- Valjean (talk) (PING me) 23:54, 12 December 2022 (UTC)

I get it, I did wrong by overusing the self-cite. But now you have cleaned all my contributions to science off Wikipedia, which I feel is overdoing the gate-keeping. Yes, self-citing is self promotion. But in this case it is also sharpening up the information on Wikipedia. PzychoPat (talk) 09:09, 13 December 2022 (UTC)

 * I won't weigh in on the particulars here, having not had time to look into them. But on a general level, the way we handle this issue is quite straightforward. If you think your own published work would be of use in an article, start a thread about it on the article's talk page. If you then find that no one is paying attention, it may be worth posting a neutral message about it at an appropriate Wikiproject or noticeboard (e.g. WP:NPOVN if you think your work is truly essential to providing due balance). But no, it is rarely overdoing the gatekeeping to revert COI material pending a positive consensus for inclusion. Generalrelative (talk) 20:31, 14 December 2022 (UTC)

Valjean, with all respect, I do not appreciate someone taking my sentence, adding a prefix of words to it which change its meaning, and then telling I am wrong. "It is not considered a conflict of interest to cite your own publications in peer reviewed journals." In the context of scientific writing, authors cite their own research often, and editors, journals, and reviewers, do not object, and scientific societies, museums, and universities publish it. It is the norm.

Furthermore Wikipedia WP:COI clearly states that, using material you have written or published is allowed if it is relevant, conforms to policies, and is not excessive.

"Conflict of interest WP:COI editing involves contributing to Wikipedia about yourself, family, friends, clients, employers, or your financial and other relationships." This is not the case in the Sexual dimorphism article. The deleted material and references involve scientific writing that has passed peer review, an editorial process, and published in journals. It is published science, not self-promotional material.

There is heading titled "Citing yourself" WP:COI

Citing yourself
Using material you have written or published is allowed within reason, but only if it is relevant, conforms to the content policies, including WP:SELFPUB, and is not excessive. Citations should be in the third person and should not place undue emphasis on your work. You will be permanently identified in the page history as the person who added the citation to your own work. When in doubt, defer to the community's opinion: propose the edit on the article's talk page and allow others to review it. However, adding numerous references to work published by yourself and none by other researchers is considered to be a form of spamming.

I think the deleted material falls within these guidelines and I don't think referencing your own research (via peer reviewed science journals), 3 or 4 times in an article of this size is excessive. WiLaFa (talk) 20:57, 14 December 2022 (UTC)

 * The deleted material and references involve scientific writing that has passed peer review, an editorial process, and published in journals. It is published science, not self-promotional material. Sounds like what you're describing is still WP:PRIMARY, however. When it comes to science, we typically take extra precaution to avoid over-emphasizing individual primary sources (i.e. "studies") as opposed to secondary sources like systematic reviews and meta-analyses. Contrary to what you seem to suggest, lots of stuff is technically "published science" which is totally inappropriate for inclusion in the encyclopedia. In all cases, the best practice is what I've described in my previous comment, and that goes double for any topic about which discretionary sanctions have been put in place (so anything to do with gender and sexuality). I'd suggest turning your attention toward making the case for inclusion of this particular content –– if that's something you'd like to see –– on its own merits. Generalrelative (talk) 23:10, 14 December 2022 (UTC)

"I'd suggest turning your attention toward making the case for inclusion of this particular content –– if that's something you'd like to see –– on its own merits." I would say it the other way around, a case should be made for excluding this particular content on its own merits (not because an editor cited their publication WP:SELFCITE). This is what I am finding a little disturbing here, nowhere has anyone addressed the content or substance of the deleted text, only pointing to guidelines that do really not support what is implied. The deleted texts appear to be appropriate, valid, and in good faith. As I asked very early on in this discussion, is there something specifically controversial or problematic about the deleted entries? This has never been address or made clear.

Reasons for the deleting text given above include - Erroneous: WP:SELFCITE and, content and supporting references were deleted and they were not redundant to existing content or citations. These link to other pages and subjects and do not address the content in question here or its merits, and WP:SELFCITE Erroneous: WP:SELFCITE and this still does not address the content or its merits.
 * "The cite was added by the author of the paper. It doesn't support any content, it was purely redundant with existing citations. MrOllie 16:07, 12 December 2022"
 * Lindenfors: COI confirmedself-cite Pascoe: self cite MrOllie 20:22, 12 December 2022
 * "It absolutely is a conflict of interest to cite your own publications in peer reviewed journals on Wikipedia, the guidelines are clear on that." MrOllie 22:07, 12 December 2022
 * I won't weight in on the particulars here, having not had time to look into them. But..... Generalrelative 20:31, 14 December 2022
 * Sounds like what you're describing is still WP:PRIMARY, however. When it comes to science, we typically take extra precaution to avoid over-emphasizing individual primary sources (i.e. "studies") as opposed to secondary sources like systematic reviews and meta-analyses. Contrary to what you seem to suggest, lots of stuff is technically "published science" which is totally inappropriate for inclusion in the encyclopedia. In all cases, the best practice is what I've described in my previous comment, and that goes double for any topic about which discretionary sanctions have been put in place (so anything to do with gender and sexuality). I'd suggest turning your attention toward making the case for inclusion of this particular content –– if that's something you'd like to see –– on its own merits. Generalrelative 23:10, 14 December 2022

"Sounds like", have you had time to look into this yet? Not all of the deleted references are primary, some are secondary. Contrary to what you seem to suggest, WP:PRIMARY says "Primary sources that have been reputably published may be used in Wikipedia, but only with care", "A primary source may be used on Wikipedia only to make straightforward, descriptive statements of facts", and to use "common sense". How and where are deleted text and references in question "over-emphasized"? They appear to me to be straightforward, statements of facts with references and consistent with WP:PRIMARY.

 * WP:SELFCITE: "Using material you have written or published is allowed within reason".
 * WP:SOURCETYPES: "Many Wikipedia articles rely on scholarly material. When available, academic and peer-reviewed publications, scholarly monographs, and textbooks are usually the most reliable sources."
 * WP:SCHOLARSHIP: "Reliable scholarship – Material such as an article, book, monograph, or research paper that has been vetted by the scholarly community is regarded as reliable, where the material has been published in reputable peer-reviewed sources or by well-regarded academic presses."
 * WP:PRIMARY, "Primary sources that have been reputably published may be used in Wikipedia, but only with care, because it is easy to misuse them."
 * WP:STICKTOSOURCE, Reliable sources: "In general, the most reliable sources are: Peer-reviewed journals"
 * WP:PSTS, "Wikipedia articles should be based on reliable, published secondary sources, and to a lesser extent, on tertiary sources and primary sources."
 * WP:PSTS, "Deciding whether primary, secondary, or tertiary sources are appropriate in any given instance is a matter of good editorial judgment and common sense"
 * WP:SECONDARYNOTGOOD: "Secondary" is not, and should not be, a bit of jargon used by Wikipedians to mean "good" or "reliable" or "usable."
 * WP:PRIMARYNOTBAD:"Primary" is not, and should not be, a bit of jargon used by Wikipedians to mean "bad" or "unreliable" or "unusable."
 * WP:PRIMARYCARE: "Material based on primary sources can be valuable and appropriate additions to articles."

Please explain why all these Wikipedia guidelines above are not applicable here. It appears to me arguments for deleting self cited edits or primary sources seem to be based on selective guidelines taken out of context, and contrary to the mainstream of the manual of style and guidelines. Wikipedia also says to assume good faith. Sure anything can be misrepresented or abused, but please show where this is the case here.

I have little interest in Wikipedia articles on gender and sexuality. My interest here is in zoology, specifically herpetology, and the integrity of referencing peer-reviewed scholarship.WiLaFa (talk) 07:56, 16 December 2022 (UTC)

 * I am rather disappointed that my words were copied from my user talk page and pasted above - I did not write any of the comments listed at the beginning of this section onto this page. I didn't even get the courtesy of a notification that I was being quoted. Please don't do that again. MrOllie (talk) 18:40, 21 December 2022 (UTC)

 * Yeah, the above WP:TEXTWALL looks a lot more like a behavioral meltdown from WiLaFa than a substantive discussion of anything. Generalrelative (talk) 18:49, 21 December 2022 (UTC)
 * Characterizing my comments as a meltdown and wall of text does not dignify a response. First one of you said the place to make an argument is not on my user talk page, now you say I am disappointed that my words were copied from my user talk page and pasted above. Where is the place? Your reasons for deleting the text were misrepresented and erroneous from the start. The deleted material did support meaningful original content and self-citing is allowed (WP:SELFCITE). After both of you failed to reply to comments above for several days, now you clam there is no consensus. Your previous objections fail to stand up to scrutiny and are not supported by Wikipedia guidelines (WP:SELFCITE, WP:SOURCETYPES, WP:SCHOLARSHIP, WP:PRIMARY, WP:STICKTOSOURCE, WP:PSTS, WP:SECONDARYNOTGOOD, WP:PRIMARYNOTBAD, WP:PRIMARYCARE).
 * A paragraph on sexual dimorphism in elephant seals was deleted, and a paragraph stating - female mammals tend to have higher white blood cell counts - was also deleted, both referencing reputable peer reviewed journals. Other than self citing and primary sources, which are both EXPLICITLY allowed, is there something specifically problematic or controversial here? Please explain the issue and why the guidelines above are not applicable here. WiLaFa (talk) 03:57, 23 December 2022 (UTC)
 * Excessive self citing is clearly not allowed, and this was an obvious case of that. Your understanding of other Wikipedia guidelines are similarly flawed - I suggest you re-read them. MrOllie (talk) 19:27, 27 December 2022 (UTC)
 * I'm sorry, but from the beginning I am not following the reasoning here: your right – I'm wrong; you understand Wikipedia guidelines – I don't. As I have asked repeatedly and first and foremost, please explain why these paragraphs are not a meaningful addition to the article? Please explain why my understanding of Wikipedia guidelines are flawed?  I have read the Wikipedia guidelines several times over, given my reasons in detail, and the guidelines not only seem clear, they seem overwhelmingly clear (WP:SELFCITE the references in question here are peer reviewed journals). Considering a subject as complex and sexual dimorphism, an article as lengthy as this one (99,788 bytes, 150 references), four self citations do not seem excessive. What is it that I am not understanding? WiLaFa (talk) 02:46, 28 December 2022 (UTC)
 * I'm still waiting for you to make a positive case for inclusion, which you do not appear to have done. Per policy, the WP:ONUS is on those seeking to add disputed content. Instead, you wrote I would say it the other way around, a case should be made for excluding this particular content on its own merits. That's not how this works. I am, by the way, still entirely open to being persuaded on the merits. But no one here is required to WP:SATISFY you. If you disagree with the way this conversation is going, you are of course free to take it to a noticeboard. Generalrelative (talk) 02:57, 28 December 2022 (UTC)
 * It was explained a couple of times in the user talk section you copied above. If you disagree with the COI guidelines, you can try to change them at WP:VPP. If you don't understand, feel free to ask at WP:TEAHOUSE. I'd rather not go over it again and again. MrOllie (talk) 02:58, 28 December 2022 (UTC)
 * It was explained a couple of times in the user talk section you copied above. If you disagree with the COI guidelines, you can try to change them at WP:VPP. If you don't understand, feel free to ask at WP:TEAHOUSE. I'd rather not go over it again and again. MrOllie (talk) 02:58, 28 December 2022 (UTC)

Providing sources
I keep getting my edits deleted because I am self-citing. Since I have been a researcher of sexual dimorphism for 25 years, I feel that there is some validity in self-citing, however (and I do not only self-cite; there are a number of interesting themes missing from this page written by others, believe it or not). But apparently, peer review is stricter on Wikipedia. This is a good method to keep scientists off Wikipedia, so I guess I'll fuck off. (Which is a bummer; this page needs to be looked over.) But if you want to improve the quality of the page, feel free to enter the following citations in the context indicated (as it is now, several claims are unsourced).

In a large proportion of mammal species, males are larger than females.

Marine mammals show some of the greatest sexual size differences of mammals, because of sexual selection and environmental factors like breeding location.

Modern day  Homo sapiens   show a range of sexual dimorphism, with average body mass between the sexes differing by roughly 15%.

Sexual dimorphism in immune function is a common pattern in vertebrates and also in a number of invertebrates. Most often, females are more 'immunocompetent' than males. PzychoPat (talk) 09:28, 25 February 2023 (UTC)

Inaccurate information in human section of article.
After reading the source material for this line in the "human" section of the article I've found that this line "In males, pain-causing injury to the peripheral nerve occurs through the microglia, while in females it occurs through the T cells (except in pregnant women, who follow a male pattern)" citing: Dance A (27 March 2019). "Why the sexes don't feel pain the same way". Nature. 567 (7749): 448–450. Bibcode:2019Natur.567..448D. doi:10.1038/d41586-019-00895-3. PMID 30918396. S2CID 85527866. Is at best misleading and at worst completly false. The article in question does not mention humans once inr regards to research actually conducted, and specifically covers pain research in mice. Additionally this is a relatively new article and research that merely suggests that the pathways for pain reception differences in human males and females MIGHT be different if the THEORETICAL differences in mice are the same. The above claim should either be moved to the general mammal section of the article or removed all together. The source material simply doesn't support what is written. Made an account just to point this out. C. Mich. Dav. (talk) 08:25, 25 July 2023 (UTC)

Male vs female strength in humans
User:Lina Magull altered some long standing edits without explanation. The changes did not appear to be useful for the following reasons. I reverted that changes. These were nearly immediately reverted back without explanation by User:Germany 6-0 Spain. Suspect that User:Germany 6-0 Spain and User:Lina Magull are the same person.
 * the original reference "Strength training for female athletes" was published in a semi-academic journal representing a professional and cited all of its sources. It had been replaced by two sources, the first of which is an unsourced and unreliable web page on a commercial site. The second site, although on a more reputable popular online magazine, is also unsourced and written by an author with no background in the subject.
 * 40-60% had been changed to 70%, with the first reference used. There is nothing in that reference that could possibly be used to indicate the figure of 70%. The second reference supplied gives a figure of 50-60%
 * 70-75% had been changed to 80-90%, with the second reference used. This figure is one derived "when you take into account body size" but its use in the Wikipedia article is for "absolute strength"
 * 40% had been changed to 30%, and 335 to 348. It is not clear where the figure 348 comes from as the suggested source, Olympic weightlifting records, has 335. Even if the figure 348 is used the difference is still = (1-348/429)*100 = 41%. Note all of the measurements in the paragraph to that point had been comparing female to male, thus the male figure must be the denominator in the formula.
 * 11% changed to 10% when the study clearly states 11% with error margins less than 0.5

The above issues need to be addressed, or else the text should return to its original condition. Jameel the Saluki (talk) 14:11, 8 November 2023 (UTC)

 * Thanks for bringing this up. I believe I've resolved the issue with these edits. Generalrelative (talk) 14:42, 8 November 2023 (UTC)
 * In the context of the entire article, and the general uncertainties involved I'm not going to fight it. Jameel the Saluki (talk) 15:03, 8 November 2023 (UTC)

Clearer caption for map turtle image?
The picture caption says: "...adult female (left) and adult male (right)," but the picture actually shows most of a third animal, and while it is possible to guess from the context what is meant, it would be clearer to specify the middle animal and the one on the right - if, of course, I have guessed right! Or to specify that the two animals on the left are females. Thoughts? FloweringOctopus (talk) 12:36, 30 November 2023 (UTC)

title: Talk:Sexual dimorphism


text:
User:Sdp/Todo

This is my todo.

Trains

 * See where I can make contributions.
 * San Francisco Municipal Railway Stations, with station templates.

Computers/Algorithms

 * Geometry
 * Line segment intersection - could there be some kind of example of scan line algorithm

Geography

 * Mountains/Ranges
 * Sierra Nevada (US)
 * Carson Range
 * Virginia Range
 * Slide Mountain (Nevada)
 * Mount Rose
 * Water
 * Kern River
 * Carson River
 * Truckee River
 * Walker River
 * Walker Lake
 * Lahontan Reservoir
 * Lake Lahontan
 * Pyramid Lake
 * Steamboat Creek
 * Valleys
 * Black Rock Desert
 * Washoe Valley, Nevada -- maybe

Also check out notable places and info from USGS GNIS.
 * http://geonames.usgs.gov/pls/gnis/web_query.gnis_web_query_form

Biography

 * Walter van Tilburg Clark
 * Robert Laxalt
 * William Ormsby
 * Adolph Sutro
 * Sandy Bowers
 * Eilley Orrum Bowers
 * George Wingfield

American History

 * Nevada
 * Nevada Localities
 * List of cities in Nevada
 * Virginia and Truckee Railroad
 * Reno, Nevada
 * Carson City, Nevada
 * Virginia City, Nevada
 * Carson County, Utah Territory

Native Americans

 * Washoe Tribe

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

title: User:Sdp/Todo


text:
Molybdenum disulfide

Molybdenum disulfide (or moly) is an inorganic compound composed of molybdenum and sulfur. Its chemical formula is .

The compound is classified as a transition metal dichalcogenide. It is a silvery black solid that occurs as the mineral molybdenite, the principal ore for molybdenum. is relatively unreactive. It is unaffected by dilute acids and oxygen. In appearance and feel, molybdenum disulfide is similar to graphite. It is widely used as a dry lubricant because of its low friction and robustness. Bulk is a diamagnetic, indirect bandgap semiconductor similar to silicon, with a bandgap of 1.23 eV.

Production
MoS2 is naturally found as either molybdenite, a crystalline mineral, or jordisite, a rare low temperature form of molybdenite. Molybdenite ore is processed by flotation to give relatively pure. The main contaminant is carbon. also arises by thermal treatment of virtually all molybdenum compounds with hydrogen sulfide or elemental sulfur and can be produced by metathesis reactions from molybdenum pentachloride.

Crystalline phases
All forms of have a layered structure, in which a plane of molybdenum atoms is sandwiched by planes of sulfide ions. These three strata form a monolayer of MoS2. Bulk MoS2 consists of stacked monolayers, which are held together by weak van der Waals interactions.

Crystalline MoS2 exists in one of two phases, 2H-MoS2 and 3R-MoS2, where the "H" and the "R" indicate hexagonal and rhombohedral symmetry, respectively. In both of these structures, each molybdenum atom exists at the center of a trigonal prismatic coordination sphere and is covalently bonded to six sulfide ions. Each sulfur atom has pyramidal coordination and is bonded to three molybdenum atoms. Both the 2H- and 3R-phases are semiconducting.

A third, metastable crystalline phase known as 1T-MoS2 was discovered by intercalating 2H-MoS2 with alkali metals. This phase has trigonal symmetry and is metallic. The 1T-phase can be stabilized through doping with electron donors such as rhenium, or converted back to the 2H-phase by microwave radiation. The 2H/1T-phase transition can be controlled via the incorporation of S vacancies.

Allotropes
Nanotube-like and buckyball-like molecules composed of are known.

Exfoliated MoS2 flakes
While bulk MoS2 in the 2H-phase is known to be an indirect-band gap semiconductor, monolayer MoS2 has a direct band gap. The layer-dependent optoelectronic properties of MoS2 have promoted much research in 2-dimensional MoS2-based devices. 2D MoS2 can be produced by exfoliating bulk crystals to produce single-layer to few-layer flakes either through a dry, micromechanical process or through solution processing.

Micromechanical exfoliation, also pragmatically called "Scotch-tape exfoliation", involves using an adhesive material to repeatedly peel apart a layered crystal by overcoming the van der Waals forces. The crystal flakes can then be transferred from the adhesive film to a substrate. This facile method was first used by Konstantin Novoselov and Andre Geim to obtain graphene from graphite crystals. However, it can not be employed for a uniform 1-D layers because of weaker adhesion of MoS2 to the substrate (either Si, glass or quartz); the aforementioned scheme is good for graphene only. While Scotch tape is generally used as the adhesive tape, PDMS stamps can also satisfactorily cleave MoS2 if it is important to avoid contaminating the flakes with residual adhesive.

Liquid-phase exfoliation can also be used to produce monolayer to multi-layer MoS2 in solution. A few methods include lithium intercalation to delaminate the layers and sonication in a high-surface tension solvent.

Mechanical properties
MoS2 excels as a lubricating material (see below) due to its layered structure and low coefficient of friction. Interlayer sliding dissipates energy when a shear stress is applied to the material. Extensive work has been performed to characterize the coefficient of friction and shear strength of MoS2 in various atmospheres. The shear strength of MoS2 increases as the coefficient of friction increases. This property is called superlubricity. At ambient conditions, the coefficient of friction for MoS2 was determined to be 0.150, with a corresponding estimated shear strength of 56.0 MPa (megapascals). Direct methods of measuring the shear strength indicate that the value is closer to 25.3 MPa.

The wear resistance of MoS2 in lubricating applications can be increased by doping MoS2 with Cr. Microindentation experiments on nanopillars of Cr-doped MoS2 found that the yield strength increased from an average of 821 MPa for pure MoS2 (at 0% Cr) to 1017 MPa at 50% Cr. The increase in yield strength is accompanied by a change in the failure mode of the material. While the pure MoS2 nanopillar fails through a plastic bending mechanism, brittle fracture modes become apparent as the material is loaded with increasing amounts of dopant.

The widely used method of micromechanical exfoliation has been carefully studied in MoS2 to understand the mechanism of delamination in few-layer to multi-layer flakes. The exact mechanism of cleavage was found to be layer dependent. Flakes thinner than 5 layers undergo homogenous bending and rippling, while flakes around 10 layers thick delaminated through interlayer sliding. Flakes with more than 20 layers exhibited a kinking mechanism during micromechanical cleavage. The cleavage of these flakes was also determined to be reversible due to the nature of van der Waals bonding.

In recent years, MoS2 has been utilized in flexible electronic applications, promoting more investigation into the elastic properties of this material. Nanoscopic bending tests using AFM cantilever tips were performed on micromechanically exfoliated MoS2 flakes that were deposited on a holey substrate. The yield strength of monolayer flakes was 270 GPa, while the thicker flakes were also stiffer, with a yield strength of 330 GPa. Molecular dynamic simulations found the in-plane yield strength of MoS2 to be 229 GPa, which matches the experimental results within error.

Bertolazzi and coworkers also characterized the failure modes of the suspended monolayer flakes. The strain at failure ranges from 6 to 11%. The average yield strength of monolayer MoS2 is 23 GPa, which is close to the theoretical fracture strength for defect-free MoS2.

The band structure of MoS2 is sensitive to strain.

Chemical reactions
Molybdenum disulfide is stable in air and attacked only by aggressive reagents. It reacts with oxygen upon heating forming molybdenum trioxide:
 * 2 + 7  → 2  + 4

Chlorine attacks molybdenum disulfide at elevated temperatures to form molybdenum pentachloride:
 * 2 + 7  → 2  + 2

Intercalation reactions
Molybdenum disulfide is a host for formation of intercalation compounds. This behavior is relevant to its use as a cathode material in batteries. One example is a lithiated material,. With butyl lithium, the product is.

Lubricant
Due to weak van der Waals interactions between the sheets of sulfide atoms, has a low coefficient of friction. in particle sizes in the range of 1–100 μm is a common dry lubricant. Few alternatives exist that confer high lubricity and stability at up to 350 °C in oxidizing environments. Sliding friction tests of using a pin on disc tester at low loads (0.1–2 N) give friction coefficient values of <0.1.

is often a component of blends and composites that require low friction. For example, it is added to graphite to improve sticking. A variety of oils and greases are used, because they retain their lubricity even in cases of almost complete oil loss, thus finding a use in critical applications such as aircraft engines. When added to plastics, forms a composite with improved strength as well as reduced friction. Polymers that may be filled with include nylon (trade name Nylatron), Teflon and Vespel. Self-lubricating composite coatings for high-temperature applications consist of molybdenum disulfide and titanium nitride, using chemical vapor deposition.

Examples of applications of -based lubricants include two-stroke engines (such as motorcycle engines), bicycle coaster brakes, automotive CV and universal joints, ski waxes and bullets.

Other layered inorganic materials that exhibit lubricating properties (collectively known as solid lubricants (or dry lubricants)) includes graphite, which requires volatile additives and hexagonal boron nitride.

Catalysis
is employed as a cocatalyst for desulfurization in petrochemistry, for example, hydrodesulfurization. The effectiveness of the catalysts is enhanced by doping with small amounts of cobalt or nickel. The intimate mixture of these sulfides is supported on alumina. Such catalysts are generated in situ by treating molybdate/cobalt or nickel-impregnated alumina with or an equivalent reagent. Catalysis does not occur at the regular sheet-like regions of the crystallites, but instead at the edge of these planes.

MoS2 finds use as a hydrogenation catalyst for organic synthesis. It is derived from a common transition metal, rather than group 10 metal as are many alternatives, MoS2 is chosen when catalyst price or resistance to sulfur poisoning are of primary concern. MoS2 is effective for the hydrogenation of nitro compounds to amines and can be used to produce secondary amines via reductive amination. The catalyst can also can effect hydrogenolysis of organosulfur compounds, aldehydes, ketones, phenols and carboxylic acids to their respective alkanes. The catalyst suffers from rather low activity however, often requiring hydrogen pressures above 95 atm and temperatures above 185 °C.

Research
plays an important role in condensed matter physics research.

Hydrogen evolution
and related molybdenum sulfides are efficient catalysts for hydrogen evolution, including the electrolysis of water; thus, are possibly useful to produce hydrogen for use in fuel cells.

Oxygen reduction and evolution
MoS2@Fe-N-C core/shell nanosphere with atomic Fe-doped surface and interface (MoS2/Fe-N-C) can be used as a used an electrocatalyst for oxygen reduction and evolution reactions (ORR and OER) bifunctionally because of reduced energy barrier due to Fe-N4 dopants and unique nature of MoS2/Fe-N-C interface.

Microelectronics
As in graphene, the layered structures of and other transition metal dichalcogenides exhibit electronic and optical properties that can differ from those in bulk. Bulk has an indirect band gap of 1.2 eV,  while  monolayers have a direct 1.8 eV electronic bandgap, supporting switchable transistors and photodetectors.

nanoflakes can be used for solution-processed fabrication of layered memristive and memcapacitive devices through engineering a / heterostructure sandwiched between silver electrodes. -based memristors are mechanically flexible, optically transparent and can be produced at low cost.

The sensitivity of a graphene field-effect transistor (FET) biosensor is fundamentally restricted by the zero band gap of graphene, which results in increased leakage and reduced sensitivity. In digital electronics, transistors control current flow throughout an integrated circuit and allow for amplification and switching. In biosensing, the physical gate is removed and the binding between embedded receptor molecules and the charged target biomolecules to which they are exposed modulates the current.

MoS2 has been investigated as a component of flexible circuits.

In 2017, a 115-transistor, 1-bit microprocessor implementation was fabricated using two-dimensional.

MoS2 has been used to create 2D 2-terminal memristors and 3-terminal memtransistors.

Valleytronics
Due to the lack of spatial inversion symmetry, odd-layer MoS2 is a promising material for valleytronics because both the CBM and VBM have two energy-degenerate valleys at the corners of the first Brillouin zone, providing an exciting opportunity to store the information of 0s and 1s at different discrete values of the crystal momentum. The Berry curvature is even under spatial inversion (P) and odd under time reversal (T), the valley Hall effect cannot survive when both P and T symmetries are present. To excite valley Hall effect in specific valleys, circularly polarized lights were used for breaking the T symmetry in atomically thin transition-metal dichalcogenides. In monolayer MoS2, the T and mirror symmetries lock the spin and valley indices of the sub-bands split by the spin-orbit couplings, both of which are flipped under T; the spin conservation suppresses the inter-valley scattering. Therefore, monolayer MoS2 have been deemed an ideal platform for realizing intrinsic valley Hall effect without extrinsic symmetry breaking.

Photonics and photovoltaics
also possesses mechanical strength, electrical conductivity, and can emit light, opening possible applications such as photodetectors. has been investigated as a component of photoelectrochemical (e.g. for photocatalytic hydrogen production) applications and for microelectronics applications.

Superconductivity of monolayers
Under an electric field monolayers have been found to superconduct at temperatures below 9.4 K.

title: Molybdenum disulfide


text:
George Saimes

George Thomas Saimes (September 1, 1941 – March 8, 2013) was an American professional football player who was a defensive back for the Buffalo Bills of the American Football League (AFL). He played college football as a fullback for the Michigan State Spartans. He won AFL championships with the Bills in 1964 and 1965.

Saimes was born and died in Canton, Ohio. In 1964, he had a career-high six interceptions and earned the first of his five American Football League All-Star Game appearances. He made The Sporting News All-AFL Team in 1964, 1965 and 1967. Former Pro Football writer and president of the Pro Football Writers Association, Larry Felser, calls Saimes "the finest open-field tackler in the league."

He achieved All-American Football League honors five times, and is a member of the American Football League All-Time Team, the Buffalo Bills' Wall of Fame, and the Greater Buffalo Sports Hall of Fame.

Saimes went on to be a professional football scout with the Blesto V Combine, the Tampa Bay Buccaneers, the Washington Redskins, and the Houston Texans. Saimes died in Canton of leukemia on March 8, 2013.

title: George Saimes