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Jughead Jones

Forsythe Pendleton "Jughead" Jones III is one of the fictional characters created by Bob Montana and John L. Goldwater in Archie Comics who first appeared in the first Archie story, from Pep Comics #22 (December 1941). He is the drummer of the Archies and is a son of Forsythe Pendleton Jones II; in one of the early Archie newspaper comic strips, he is identified as John Jugworth Jones III (and in one strip, likely due to a continuity error, as Forsythe Van Jones). He has a white sheepdog named Hot Dog and a younger sister, Forsythia "Jellybean" Jones.

Jughead (shortened to Jug or Juggie) is the best friend of vocalist/guitarist Archie Andrews. Jughead is a smart, sharp-tongued, laid-back, and eccentric high school student. He is obsessed with eating food and in some storylines is asexual. Most see him as being lazy. He can be identified by his long nose, half-closed eyes, "S" sweatshirt, and whoopee cap (a crown-like warped and trimmed fedora hat). Jughead is portrayed by Cole Sprouse in the live-action CW series, Riverdale and Mihir Ahuja in The Archies.

Concept and creation
Bob Montana stated that Jughead was a character he imagined, unlike other characters in the series who were based on people he knew. Montana's widow, Peg Bertholet, stated that high school friend of Montana's named Skinny Linehan supposedly had some of Jughead's peculiar traits. Bertholet has stated that the "S" insignia refers to a location called Skunk Hill in Haverhill, Massachusetts which Montana turned into Squirrel Hill. The "S" alludes to a combination of the location and Montana's elementary school athletic team near Haverhill called the Tigers. Bertholet has stated that "S" stands for "'Squirrel Hill Independent Tigers,' and you couldn't abbreviate it any other way."

History and character
Jughead generally has a characteristic wry and sarcastic sense of humor. He is considered a bit of an oddity, but prefers his nonconformism as opposed to going along with others' styles. His many quirks make him the butt of teasing and abuse from Reggie, Veronica, and even other classmates and teachers. Many episodes involve Reggie and Jughead trying to outdo one another with pranks and bets, and Jughead almost always comes out the victor. He is revealed to be extremely clever and creative when necessary and he often takes advantage of Reggie's and his other tormentors' weaknesses (and has fun all the while).

In the earlier comics, a running gag involved various characters trying to discover Jughead's real name, while Jughead thwarted their efforts. In one story, Archie Andrews and Reggie Mantle go to the school office, where a woman tells them that Jughead's real first name is Steve. After Archie and Reggie leave the office, the audience learns that the woman is actually Jughead's aunt who has just lied as a favor to Jughead to help keep his real first name (Forsythe) hidden. The earliest stories indicated that the mention of his name drove girls wild for him. The first of these appeared in "Jughead" #159 (August 1968). In Little Archie #49 (September 1968), Miss Grundy revealed his real name at the start of class, and it drove girls wild. In a later story (issue #1 of "The Jughead Jones Comics Digest," June 1977) we find out he is named after his ancestor, Forsythe P. Jones, who is an American hero. For a brief time, Jughead started to use his given name in honor of his ancestor. After learning that this ancestor was married nine times, Jughead reverted to his nickname.

Another mystery that follows Jughead's character is the meaning of the "S" on his sweatshirt. This remains a mystery to this day, although many stories have hinted at a meaning. In Jughead #30 (1992), when his psychiatrist, Sara, asked him "why an 'S'?" he replied "I dunno! My third cousin was called skinny..." The triangular banner on the cover of issue 140 of Archie & Friends shows that the "S" stands for Silby, as in Silby High School, which he attended for a few months as a freshman. At one time after his sweater was filled with holes due to what he thought was a moth when it was actually a chemical accident caused in lab class, he reveals that he simply likes the letter S and finds it "compatible," because the letter can stand for "soup, sandwich, steak and all kinds of goodies!" after his friends ask him. Betty rolls her eyes at the explanation and adds, "S stands for "sorry I asked"!" Another theory is that, as he is a non-conformist, he wears an "S" as opposed to his classmates who wear sweaters adorned with an "R" which stands for Riverdale.

Appetite and love for food
Jughead is known for his love of food, especially hamburgers, and his ability to consume absurdly large quantities in a single sitting without getting sick or gaining weight, although he often sports a pot-belly immediately after a particularly large meal. Jughead is a preferred customer of most of Riverdale's food establishments, especially Pop Tate's Chock'lit Shoppe, except when he is behind on paying his usually lengthy tab. In one story, he was given a "Restaurant Club Card" and ate out at high-class restaurants until he found out how much interest the card charged, and Pop Tate loaned him the money on the condition that he eat exclusively at the Chock'lit Shoppe. His ability to eat so much food without gaining weight is attributed to a very rare and implausibly high metabolism. He once claimed that he weighed 300 pounds after a meal, although he is usually portrayed as slim and healthy.

Jughead's special abilities concerning food extend to being able to identify food in a sealed can by smell, and being able to detect the slightest flaws in food preparation by taste. As such, he is a respected food critic, as well as a gourmet chef himself. One time, when he sought out Miss Grundy's help with his creative writing, she suggested that he write about a subject he knew, leading to the "Forsythe P. Jones Cookbook".

Jughead often participates in eating contests, usually winning outright, or else easily coming from behind after comic distractions, and often with room to spare while the competitor retires unwell. In a citywide eating contest, he ate a colossal burger made up of sixteen different burgers. Jughead also set two world records for eating pizza; one for speed-eating a pizza, and another for eating the most pizzas in one sitting: twelve. Jughead's appetite is so large that even if he eats shortly before such contests, it does not affect his performance. For example, a rival high school once sent a girl, Jane Dough, to take Jughead to various restaurants and feed him as much as possible. Amazingly, Jughead still managed to win the contest. He explained to Jane that top athletes need to train constantly in order to stay in shape, and she actually helped him "train" for the contest.

One running gag depicts Jughead visiting restaurants that promise "all you can eat" special deals, with the devastated restaurateur closing down as Jughead leaves.

Despite his appetite, Jughead is not known to be stingy with food, or to let others go hungry. When a store selling penny candy opened in Riverdale, he spent his whole allowance on a huge bag of candy, only to meet a penniless young boy outside the shop. Jughead wrestled with his desire, but he chose to give the candy to the boy. In a similar story, Jughead met a homeless person who liked the same kind of pizza as he did, and decided to give him the pizza he had just purchased. In another story, after winning three pizzas a week for six months for being a pizzeria's one-millionth customer, he donated them all to a soup kitchen where he volunteered.

Because of his well-known food obsession, Jughead was shown eating a hamburger on the facades of the short-lived Archie's Family Restaurants.

Jughead's hat
Jughead is almost always seen wearing his trademark beanie with both a round and square pin. This type of crown-shaped cap, called a whoopee cap, sometimes a "Jughead cap" or "crown", was popular among boys in the 1930s and 1940s. It was made from a man's felt fedora hat with the brim trimmed in a zig-zag and turned up. Bottle caps could be "pinned" in place using the cap's removable cork lining. In the 1920s and 1930s, college freshmen were sometimes required to wear them for initiation purposes, and such caps were often worn by mechanics. Similar caps have appeared on other comic book/strip, cartoon, and children's book characters such as Eddie Stimson in Little Lulu, Melvin Wisenheimer in Little Audrey, Skuzz in The Berenstain Bears, and Bugs Meany in Encyclopedia Brown as well as on Goober Pyle on The Andy Griffith Show and Jeff Goldblum's character "Freak #1" in Death Wish. Jughead's hat was recolored in black in the Filmation cartoons and pink in The New Archies. Over the course of the character's publication, Jughead's hat has evolved from a modified fedora to its more recognisable "crown" appearance.

Though some view the hat as strange and immature, Jughead considers it a good luck charm and when it is taken from him, misfortune comes his way. While on the school baseball team, Jughead was pulled aside and reprimanded by school principal Mr. Weatherbee for wearing the hat instead of a proper baseball uniform cap. Jughead complied, but then started performing so badly that Weatherbee was forced to relent.

In the "Time Police" comic, there is a double of his beanie given to him by an unknown benefactor (later revealed to be himself) that allows him to travel in time.

Some stories showed him wear a unique pin on his hat which attracts many girls to him, so he hid it to avoid the crowd of girls rushing him.

The hat also seems to define part of Jughead's personality. One story has the gang try to convince him to try a different hat, but it is revealed that whatever hat he tried on changed his personality to suit the hat. When they had him try on a detective hat, he focused on clues that would have gotten Archie in trouble with Betty and Veronica, and took a hair from Reggie's sweater that implied that he sneaked a date with Midge behind Moose's back (the look on both of their faces imply he was on to something). Jughead also stated that he felt naked without a hat. Finally, Veronica gave him a special hat to try on. When he did, everyone said it suited him (it was an ugly thing but looked comical. She said she was saving it for a Mad Hatter party). Jughead tried wearing it for a day at school, but scared several students, teachers, and even Miss Beazly the cafeteria lady) they begged him to go back to his trademark hat. When he asked what they'd do if he did, they offered him a platter of hamburgers and he happily agreed.

In Jughead and Friends Digest #25 story "The Secret of Jughead's Hat" his cap is destroyed in a laundry accident. Wendy Weatherbee (Principal Weatherbee's niece) replaces the lost hat by doing exactly as explained above when she takes an old fedora and cuts it and shapes it to remake the whoopee cap or crown.

Family and friends
Jughead's best friend is Archie Andrews, despite their personality difference. Archie was the first person that Jughead met upon moving to Riverdale, and he is often dragged into Archie's schemes and antics. Jughead is usually the first one to bail Archie out of trouble (though some times he only makes things worse). Jughead, extremely loyal, is willing to do almost anything to help his friend, something that Archie occasionally takes for granted.

Reggie Mantle is another one of Jughead's close friends, though his and Jughead's relationship is defined by their constant competition. Reggie never loses an opportunity to insult Jughead ("needle-nose" being his favorite nickname) and Jughead often responds with tricks to aggravate Reggie. Though it often appears they hate each other, and neither will admit otherwise, they really do care for one another. Jughead will even help Reggie escape being injured when Moose Mason is angry with him.

Alongside Archie, Betty Cooper frequently slips into the best friend role for Jughead in the comics. Their mutual love and appreciation for food (she cooks, he eats), and continuously going to bat for each other have made their friendship a stronghold in the comics. While generally disinterested in matters of the heart, Jughead frequently stands up for Betty when Archie breaks her heart. In one comic, Jughead tells Betty that if he were to ever kiss a girl willingly, it would be her.

Jughead and Veronica Lodge are constantly arguing. Veronica cannot stand his laid-back attitude witticisms, and Jughead enjoys teasing her and making her lose her temper with clever insults. Their relationship would be considered that of "frenemies". Although at times, he relishes causing her to get angry because sometimes he sees her as an uncaring selfish snob. He once told Veronica he was "mad with passion" for her, and began popping up wherever she went, to get her off his back after she criticized him publicly. They were once cast together in a school play, which required them to kiss. Due to the way Jughead kissed her, she was caught up in the moment and fell in love with him for a while. However, Jughead managed to get her over her crush, with the help of a garlic and onion sandwich.

Jughead's other friends include Dilton Doiley and Moose Mason. Other than Dilton, Jughead probably gets along with Moose better than the other boys because of his non-confrontational attitude (and his lack of interest in Moose's girlfriend Midge). Jughead's nerdy ways and lack of interest in sports and girls probably account for how well he gets along with Dilton.

Jughead's family includes his father, also named Forsythe, his mother Gladys, and in later comics, his younger sister Jellybean. He also has many eccentric relatives including slightly-addled Uncle Herman, or "Doc Jones", a daffy and slightly pompous inventor whose creations usually wreak havoc on Jughead and/or his friends and his lookalike younger cousin, Souphead. Other one-time relatives appear frequently. Jughead also tells many stories of his ancestors, who prove to be quite as interesting as himself. A 1970s "Archie" cartoon episode featured Jughead's paternal grandparents—both of whom resemble Jughead.

Another acquaintance of Jughead's is Trula Twyst, Riverdale High's budding pop psychologist, who is constantly trying to analyze Jughead to determine what makes him so odd. The two share a strange love/hate relationship that would have gone much smoother had they not met the way they did- Trula tricked Jughead into dating her in order to become more popular.

In one story, Jughead claimed his great-grandmother was a Native American "from the Pawtuxet tribe," despite the fact that the Patuxet were killed off by 1622. In another story from the same era, he claimed his great-great-grandfather was "an eskimo," who was "the only cop north of Nome...'Ol' Bluenose Jones' they called him!" It is likely that neither of these claims are meant to be taken seriously. In both stories he also used his claims to make fun of Veronica, which suggests more that his comments were meant as jokes, since Jughead has a history of making up fibs to tease Veronica and other opponents.

In the "Mad Magazine" universe, Jughead's doppelgänger is nicknamed Bottleneck. Bottleneck wears a beanie that resembles a broken bottleneck. His best friend (and fellow juvenile delinquent) is Starchie.

Miniseries
Jughead's Time Police was a series that began in 1990 featuring Jughead as a hero of the 29th century and a member of the Time Police, an organization that ensures history to remain the same for the future's sake. In this series, the beanie gives Jughead the ability to time travel by thinking. With his supervisor, Marshal January McAndrews, Jughead repairs disturbances in the past. The series was rebooted in 2019, with Jughead building a time machine to undo the mistakes he has made, forcing January McAndrews to intervene.

Other spin-offs include Jughead's Diner in 1990, where he ran a diner with an eclectic cast of patrons; and Jughead's Fantasy, resulting from Jughead's Folly, lasted for three issues and featured Jughead's dreams of various alter-egos, including "Sir Jugalot", "Peter Goon--Private Eye", and "Son of Hercules". Jughead also featured in Explorers of the Unknown, playing Squint, a daredevil escape artist.

Sexuality
Jughead is known for his lack of interest in romantic relationships with anyone. Jughead's philosophy on romantic relationships, gained from observing Archie's romantic entanglements, is that dating makes life complicated and costs money that could be spent on hamburgers. Ironically, his apathy toward women often attracts rather than repels them. His most ardent admirer is Ethel Muggs, an awkward but very friendly girl who chases after Jughead at every opportunity, despite Jughead's constant and blunt refusals. Later story-lines showed a decrease in her obsession with him, and even show her dating other guys, making Jughead jealous. Jughead secretly enjoys the attention, although he claims that he puts up with Ethel's company only because she cooks for him. He has shown romantic interest in her on rare occasions, and eventually falls in love with her in the Life With Archie: The Married Life series, where the "Archie Marries Veronica" stories end with Jughead and Ethel's wedding.

In 2016, Jughead's orientation was confirmed to be asexual in the stories of Chip Zdarsky (and later Ryan North and Mark Waid) for the Jughead comics as part of the New Riverdale line. Zdarsky said of his run on the book that "the next writer could make him discover girls or boys or both and that's totally fine. There have been iterations of Jughead over the decades where he has been interested in girls, so there's room to play around if someone was inclined. For me though, I like an asexual Jughead." He later tweeted that he viewed Jughead as "ace and probably demi-romantic, but for the purposes of his teen years, aro." Both Riverdale fans in the asexual community and Cole Sprouse, who portrays Jughead in The CW's Riverdale, have complained of asexual erasure in mainstream television and expressed desire to see the character's asexuality explored. However, Sprouse later noted that the Jughead Zdarsky created is the only asexual version so far. At the same time, he said that Jughead is aromantic in the classic Archie stories, "a different thing [from asexuality] but deserves attention as well."

A group of girls formed the UGAJ (United Girls Against Jughead) in an effort to get him interested in romance, using methods such as computers or food, though ultimately failing.

For his first 40 years or so of the comic, Jughead often claimed to dislike girls, but a shift in societal attitudes has caused later writers and fans to try different ways of explaining this, such as past heartbreak from childhood romance, bad impressions from Veronica and Ethel, and in the 2015 reboot, asexuality. There has never been one consistent canon explanation for Jughead's avoidance of girls and dating. In one story, Jughead declares, "I don't hate girls—I just love food more!" In the story "Phood Phobia", Archie and Dilton Doiley discover a hidden layer to this: it turns out that Jughead is actually nervous around girls, and he turns to food for comfort. When confronted with this, Jughead is stunned; finding out that girls are the reason he enjoys food so much makes him lose his appetite. In another story, when Jughead saw that Miss Grundy was upset on her birthday, he rallied the other students to cheer her up.

In "A Lass From The Past", written by Nate Butler and first appearing in Jughead #5 (April 1988), Jughead explains the reason he does not chase after girls is because of a childhood heartbreak, sustained before he moved to Riverdale. Little Jughead befriended Joani and they had a puppy love relationship. Jughead's family moved to Riverdale and he had to leave Joani behind. Determined to not endure heartbreak again, he swore off girls, keeping little Joani's picture in his wallet as a reminder. That changed when Debbie moved to town (in "Jughead's Journal," written by Rod Ollerenshaw and also first appearing in Jughead #5), and Jughead began to overcome his old heartbreak as they started dating. However, Joani suddenly visits town. Now a young woman, she tells Jughead that she never forgot him and still has a crush on him, and they share their first kiss. Before Jughead decides whether he wants to pursue a relationship with Joani, she leaves him, but with a promise that they will be together again. The comic even had Jughead say, "Sometimes, life is just more interesting than burgers and shakes." For a while, Debbie and Joani formed Jughead's own love triangle, but fans did not like it, so both girls disappeared and Jughead reverted to his classic independent lifestyle. A few years later, a girl named Trula Twyst appeared. She tends to drive Jughead crazy with her ability to predict his next moves, and they developed a love-hate relationship.

Another thread that has run through stories involves a psychic experience he is supposed to have had, caused by an odd pin he wears on his hat. In the early 1990s, Jughead had three girlfriends: Debbie, Joani, and January McAndrews. The latter is Archie's descendant in the future, who starred with Jughead in Jughead's Time Police, a short-lived spinoff comic about their adventures traveling through time.

Musical interests
Jughead was the drummer for The Archies. In one four-part story, which included many flashbacks of Jughead's life, Archie had commented that the reason he'd chosen the position of drummer was that he was too introverted to play at the front of the stage. Another reason was that he could put food in his drums to eat while he played.

He has also professed a love for jazz music, once detailed in an issue of Jughead Magazine where he develops an obsession with an obscure jazz drummer named "Crazy" Willie Jim. After collecting his records, Jughead finally met Jim, who was now very old, ailing and reclusive, playing on a street corner. Jughead convinced Jim that he was trustworthy and they became fast friends. Jim even played with The Archies at one of their gigs. Jim died very soon after, so Jughead sat in with Jim's friends on the corner to play one last, mournful version of "St. James Infirmary Blues".

Special abilities
In spite of his reputation as slow and lazy, Jughead is frequently shown to be extremely intelligent, and often surprises his skeptical friends (notably Reggie Mantle and Veronica Lodge) with his vast knowledge on a wide variety of subjects, including history, Shakespeare, sports, and science. In several issues, Jughead has demonstrated that his IQ is well above average. He is an extremely good student, which exasperates his teachers when he sometimes pays them no attention.

His intelligence varies from story to story. In many cases, he has trouble keeping decent grades, but was once given an award for being the best student in the school. Once, in Little Archie, it was revealed that as a student, Jughead was second only to Dilton Doiley. His intelligence is displayed by his sharp wit, the occasional deep insight, and the odd chance he gets to upstage or outsmart Reggie Mantle. In one issue, Mr. Weatherbee tries to cut down on Jughead's food consumption, only to realize that Jughead's brain stops functioning without massive amounts of food. Professor Flutesnoot implies that Jughead's brain burns all the calories, which keeps him thin.

Jughead is also a talented artist, and refers to his works as his "Dipsy Doodles", which feature in one-page comic strips. Often, what he paints comes to life or becomes a real, three-dimensional object. Another recurring gag, featured in the 1960s, was "Professor Jughead", where he would wear a gown and mortarboard and lecture to his fellow teenagers about subjects he considered relevant. However, the content of the lesson was often nonsensical and useless in real life. Professor Jughead's Loony Laws was a strip in which he presented various dumb laws. One strip explores the fact that Jughead is seldom drawn with his eyes open by noting that Jughead has the unusual ability to "see" with his eyes completely shut, and not see with them open.

In his spare time, he enjoys playing video games, reading comic books, and skateboarding. It was also noted in one issue that he has an interest in Japanese anime and manga as well, with titles such as Sailor Lunar, Dragon Tall 33, Tech Robo, and Tragic Knight Sayearth. In the late 1980s, Jughead became obsessed with the skateboarding subculture, and his interests and taste in fashion were revamped to fit this. A number of short-lived characters were added to the Jughead comics, including his paraplegic African-American crush Anita; blind rival for Ethel's affections Jeff and his guide dog Spike; and heavy metal band The Potholes. However, this makeover only lasted for a few years.

Jughead rarely takes an interest in sports, but has a few unexpected athletic talents. These are often side effects of his other activities. For example, he is a very fast runner due to his constant evasion of Ethel and his determination to be at the front of the lunchline every day. Coach Kleats often tries to recruit him for various school teams, usually without longterm success. Over the years, he has been seen as a basketball player, baseball pitcher, martial artist, swimmer, dancer and gymnast.

Many stories revolve around other characters making comments about Jughead's appetite. One story has Dilton Doiley making calculations to scientifically prove that it's impossible for Jughead to eat the way that he does, and even convinces Pop Tate to cook everything Jughead ate earlier to prove it. When the entire gang isn't paying attention, Jughead ate all the food and ended the story by saying that if they didn't believe it they could make the food and he'd eat it again. Another story has Jughead going against a guy from another group in an eating contest. The rival gang sends a girl to feed Jughead to fill him up the night before in an effort to cheat but he manages to win anyway. In still another, Archie expresses concern over Jughead's eating and lack of exercise, which prompts Reggie to show off lifting a single crate of Pop's bottles over his head. Jughead helps Pop by effortlessly lifting three crates at once and carrying them to the back room, stunning Archie and Reggie. Unnerving them even more, he rips out a stool that Pop said he could take for a souvenir (he was replacing his counter stools later that day) with one hand again with no effort. In that story, he says he eats to get strong, cracking up Archie and Reggie, but they change their mind when they see he's very strong, and even take up eating in an effort to get strong, with no success.

Often, when Jughead attempts to join a team, he ends up with an undesirable menial task, such as water-boy or equipment manager. However, he often takes part in less strenuous school activities, such as the school newspaper, the Blue and Gold. His reputation as a food critic and his unbiased views of the school teams make him a valuable member of the staff. In some stories, Jughead has been shown to have supernatural abilities that are never seen again. These include controlling weather, giving the evil-eye, learning the skills presented in any book he reads, and predicting the future.

In the "Super Teens" stories (where several of the main Archie characters are secretly superheroes), Jughead could become Captain Hero, gaining a caped costume and more muscular physique (varying from story to story), but retaining his crown-shaped cap. Captain Hero appeared when Jughead recites the magic incantation (similar to Green Lantern's oath):

Teeny weeny magic beanie pointing towards the sky; give me muscle, power, vigor - form a super guy!

Captain Hero often seemed to possess just the right powers for the problem at hand. These were never completely defined, but he maintained certain "stock" superhuman powers, such as flight, enhanced strength and resistance to injury. Early on, Captain Hero was often the most serious and competent of the Super Teens, and the others would defer to his leadership, in contrast to Jughead's perceived status as Archie's sidekick and a generally lazy individual.

Hot Dog
Hot Dog is a long-haired mutt who resembles a white Old English Sheepdog. He belongs to Jughead, although when he first appeared in Pep Comics #224 (December 1968), he belonged to Archie. Hot Dog switched owners frequently in his early appearances, but was eventually given a permanent home with Jughead.

Hot Dog usually thinks like a human, in that his thoughts are presented in thought bubbles. He is lazy, constantly hungry, and, much like Jughead, has a dislike for Reggie Mantle.

Hot Dog is usually considered a member of Archie's Gang. He tends to be attracted to Veronica Lodge’s pedigreed dogs, and even had a litter of puppies with one of them, a poodle named Lucretia, much to Veronica's chagrin. In the 1970s series Sabrina the Teenage Witch, Hot Dog has a sidekick, Chili Dog, who is smaller and red-haired. A running gag is the two dogs' "battles" with Sabrina's cat Salem Saberhagen. In the alternate universe limited series Jughead's Pal, Hot Dog, when Jughead's family objects to Hot Dog living indoors because he is covered in dirt, Dilton Doiley builds Hot Dog a doghouse full of whimsical inventions. Hot Dog's sidekick in that short-lived series is a chihuahua named Pablito.

In other media
In the Filmation animated series The Archie Show, Hot Dog is the mascot for The Archies and is often portrayed as pretending to "conduct" the band.

Hot Dog appears in Archie's Weird Mysteries, once again as Jughead's dog. In this continuity, however, Jughead is shown to own multiple pets, so he isn't seen very often. Sometimes, Hot Dog is affected by the surreal occurrences that plague Riverdale. For instance, in the episode "Twisted Youth", he is transformed back into a puppy as a result of drinking some age-reversing water.

Life with Archie: The Married Life
Jughead appears in the 2010 Life with Archie: The Married Life. In this series, Jughead has taken over Pop's from Pop Tate and has renamed it Jughead's, which later spanned a franchise in each respective universe. He ended up abandoning the franchise to operate the original shoppe in Riverdale. In this series, he ends up marrying Midge Klump in one universe, and Ethel in the other.

Afterlife with Archie
Jughead appears in the first issue of 2013's Afterlife with Archie before being bitten by a resurrected Hot Dog, which transforms him into a zombie. He is referred to as "Patient Zero" in terms of being the first one affected. However, the eighth issue reveals that Jughead is a ghost and his soul is no longer in his body; whatever is controlling his corpse isn't him.

Jughead: The Hunger
In this 2017 Archie Horror spin-off, Jughead is a werewolf responsible for a number of murders in Riverdale and becomes known as "The Riverdale Ripper." He and Archie realize he's a werewolf after he murders Dilton during a full moon. The next day, Betty reveals that he comes from a long line of lycanthropes dating back to medieval England and that her ancestors have always been there to stop them. Not wanting Betty to murder his friend, Archie suggests going to the botanical gardens to cure Jughead with Wolfsbane. This works for a couple of months, but after it wears off and Jughead murders Reggie in his wolf state, he leaves town with Hot Dog as he knows Betty wouldn't give him a second chance.

Animated

 * Jughead appeared in The Archie Show, a 1968 animated series produced by Filmation. He also appeared in the various spin-offs produced in the same format. He was voiced by Howard Morris.
 * Jughead appeared in the animated video for "Sugar, Sugar", by The Archies, as the band's drummer.
 * Jughead was featured in a Filmation-animated segment for Sesame Street spotlighting the letter J.
 * A short-lived show in the 1970s, Archie's TV Funnies, featured other comic strip characters, such as Broom-Hilda and Smokey Stover. Archie introduced each educational short, like a lesson on the importance of bathing from Nancy and Sluggo.
 * Another show, The U.S. of Archie, depicted Archie and the gang as themselves in different historical eras. The goal was to teach history.
 * Jughead appeared in The New Archies, a 1987 re-imagining of Archie and the gang. Jughead was portrayed as a pre-teen in junior high. He was voiced by Michael Fantini.
 * Jughead appeared in Archie's Weird Mysteries, voiced by Chris Lundquist.
 * In The Simpsons, Jughead, Moose, Archie, and Reggie made a cameo beating up Homer Simpson in "Sideshow Bob Roberts".

Live-action

 * Derrel Maury played Jughead in "Archie", a 1976 episode of the ABC Saturday Comedy Special; this was intended to be the pilot for a new series, which never materialized. He reprised this role in the 1978 TV-movie The Archie Situation Comedy Musical Variety Show.
 * Jughead appears in Archie: To Riverdale and Back Again, a 1990 TV movie which was broadcast on NBC, portrayed by Sam Whipple. Set fifteen years after his graduation from high school, the movie depicts Jughead as a psychiatrist who owns a successful private practice outside of Riverdale. He is also divorced and raising his young son Jordon on his own, who Archie jokingly refers to as Jughead Junior.
 * Jughead appears in Sgt. Kabukiman N.Y.P.D., a 1990 parody superhero comedy film created by Troma Entertainment, portrayed by Brick Bronsky.
 * Jughead is a main character in Riverdale, a drama series on The CW, where he is portrayed by Cole Sprouse. This version of Jughead is markedly different from the comic character, exhibiting a darker, moodier demeanor and is not overly obsessed with food, eating normally like most people. In the show, Jughead wears an ordinary dark gray knitted hat with points and pins, but appears in a dream sequence wearing his distinctive crown cap and "S" sweatshirt. His mother and sister are mentioned but absent (until Season 3), having left for Toledo due to his father's drinking. His father, F.P., is leader of the Southside Serpents, and Jughead, choosing not to live with him, is homeless. In the first-season finale, the Serpents offer Jughead one of their jackets, essentially making him an honorary member. In the second season, he undergoes an initiation that includes a brutal beating to become a full-fledged member. Over time, he becomes a de facto leader of the teenagers in the gang, and in the second-season finale, after he attempts to save the Serpents from a fight with a rival gang that badly outnumbers them by trading himself, F.P. retires and names him as his successor.

title: Jughead Jones


text:
Wrought iron

Wrought iron is an iron alloy with a very low carbon content (less than 0.05%) in contrast to that of cast iron (2.1% to 4.5%). It is a semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight), which give it a wood-like "grain" that is visible when it is etched, rusted, or bent to failure. Wrought iron is tough, malleable, ductile, corrosion resistant, and easily forge welded, but is more difficult to weld electrically.

Before the development of effective methods of steelmaking and the availability of large quantities of steel, wrought iron was the most common form of malleable iron. It was given the name wrought because it was hammered, rolled, or otherwise worked while hot enough to expel molten slag. The modern functional equivalent of wrought iron is mild steel, also called low-carbon steel. Neither wrought iron nor mild steel contain enough carbon to be hardened by heating and quenching, but true wrought iron is much more corrosion-resistant.

Wrought iron is highly refined, with a small amount of silicate slag forged out into fibers. It comprises around 99.4% iron by mass. The presence of slag can be beneficial for blacksmithing operations, such as forge welding, since the silicate inclusions act as a flux and give the material its unique, fibrous structure. The silicate filaments in the slag also protect the iron from corrosion and diminish the effect of fatigue caused by shock and vibration.

Historically, a modest amount of wrought iron was refined into steel, which was used mainly to produce swords, cutlery, chisels, axes, and other edged tools, as well as springs and files. The demand for wrought iron reached its peak in the 1860s, being in high demand for ironclad warships and railway use. However, as properties such as brittleness of mild steel improved with better ferrous metallurgy and as steel became less costly to make thanks to the Bessemer process and the Siemens–Martin process, the use of wrought iron declined.

Many items, before they came to be made of mild steel, were produced from wrought iron, including rivets, nails, wire, chains, rails, railway couplings, water and steam pipes, nuts, bolts, horseshoes, handrails, wagon tires, straps for timber roof trusses, and ornamental ironwork, among many other things.

Wrought iron is no longer produced on a commercial scale. Many products described as wrought iron, such as guard rails, garden furniture, and gates are made of mild steel. They are described as "wrought iron" only because they have been made to resemble objects which in the past were wrought (worked) by hand by a blacksmith (although many decorative iron objects, including fences and gates, were often cast rather than wrought).

Terminology
The word "wrought" is an archaic past participle of the verb "to work", and so "wrought iron" literally means "worked iron". Wrought iron is a general term for the commodity, but is also used more specifically for finished iron goods, as manufactured by a blacksmith. It was used in that narrower sense in British Customs records, such manufactured iron was subject to a higher rate of duty than what might be called "unwrought" iron. Cast iron, unlike wrought iron, is brittle and cannot be worked either hot or cold.

In the 17th, 18th, and 19th centuries, wrought iron went by a wide variety of terms according to its form, origin, or quality.

While the bloomery process produced wrought iron directly from ore, cast iron or pig iron were the starting materials used in the finery forge and puddling furnace. Pig iron and cast iron have higher carbon content than wrought iron, but have a lower melting point than iron or steel. Cast and especially pig iron have excess slag which must be at least partially removed to produce quality wrought iron. At foundries it was common to blend scrap wrought iron with cast iron to improve the physical properties of castings.

For several years after the introduction of Bessemer and open hearth steel, there were different opinions as to what differentiated iron from steel; some believed it was the chemical composition and others that it was whether the iron heated sufficiently to melt and "fuse". Fusion eventually became generally accepted as relatively more important than composition below a given low carbon concentration. Another difference is that steel can be hardened by heat treating.

Historically, wrought iron was known as "commercially pure iron"; however, it no longer qualifies because current standards for commercially pure iron require a carbon content of less than 0.008 wt%.

Types and shapes
Bar iron is a generic term sometimes used to distinguish it from cast iron. It is the equivalent of an ingot of cast metal, in a convenient form for handling, storage, shipping and further working into a finished product.

The bars were the usual product of the finery forge, but not necessarily made by that process:
 * Rod iron—cut from flat bar iron in a slitting mill provided the raw material for spikes and nails.
 * Hoop iron—suitable for the hoops of barrels, made by passing rod iron through rolling dies.
 * Plate iron—sheets suitable for use as boiler plate.
 * Blackplate—sheets, perhaps thinner than plate iron, from the black rolling stage of tinplate production.
 * Voyage iron—narrow flat bar iron, made or cut into bars of a particular weight, a commodity for sale in Africa for the Atlantic slave trade. The number of bars per ton gradually increased from 70 per ton in the 1660s to 75–80 per ton in 1685 and "near 92 to the ton" in 1731.

Origin

 * Charcoal iron—until the end of the 18th century, wrought iron was smelted from ore using charcoal, by the bloomery process. Wrought iron was also produced from pig iron using a finery forge or in a Lancashire hearth. The resulting metal was highly variable, both in chemistry and slag content.
 * Puddled iron—the puddling process was the first large-scale process to produce wrought iron. In the puddling process, pig iron is refined in a reverberatory furnace to prevent contamination of the iron from the sulfur in the coal or coke. The molten pig iron is manually stirred, exposing the iron to atmospheric oxygen, which decarburizes the iron. As the iron is stirred, globs of wrought iron are collected into balls by the stirring rod (rabble arm or rod) and those are periodically removed by the puddler. Puddling was patented in 1784 and became widely used after 1800. By 1876, annual production of puddled iron in the UK alone was over 4 million tons. Around that time, the open hearth furnace was able to produce steel of suitable quality for structural purposes, and wrought iron production went into decline.
 * Oregrounds iron—a particularly pure grade of bar iron made ultimately from iron ore from the Dannemora mine in Sweden. Its most important use was as the raw material for the cementation process of steelmaking.
 * Danks iron—originally iron imported to Great Britain from Gdańsk, but in the 18th century more probably the kind of iron (from eastern Sweden) that once came from Gdańsk.
 * Forest iron—iron from the English Forest of Dean, where haematite ore enabled tough iron to be produced.
 * Lukes iron—iron imported from Liège, whose Dutch name is "Luik".
 * Ames iron or amys iron—another variety of iron imported to England from northern Europe. Its origin has been suggested to be Amiens, but it seems to have been imported from Flanders in the 15th century and Holland later, suggesting an origin in the Rhine valley. Its origins remain controversial.
 * Botolf iron or Boutall iron—from Bytów (Polish Pomerania) or Bytom (Polish Silesia).
 * Sable iron (or Old Sable)—iron bearing the mark (a sable) of the Demidov family of Russian ironmasters, one of the better brands of Russian iron.

Quality

 * Tough iron: Also spelled "tuf", is not brittle and is strong enough to be used for tools.
 * Blend iron: Made using a mixture of different types of pig iron.
 * Best iron: Iron put through several stages of piling and rolling to reach the stage regarded (in the 19th century) as the best quality.
 * Marked bar iron: Made by members of the Marked Bar Association and marked with the maker's brand mark as a sign of its quality.

Defects
Wrought iron is a form of commercial iron containing less than 0.10% of carbon, less than 0.25% of impurities total of sulfur, phosphorus, silicon and manganese, and less than 2% slag by weight.

Wrought iron is redshort or hot short if it contains sulfur in excess quantity. It has sufficient tenacity when cold, but cracks when bent or finished at a red heat. Hot short iron was considered unmarketable.

Cold short iron, also known as coldshear, colshire, contains excessive phosphorus. It is very brittle when cold and cracks if bent. It may, however, be worked at high temperature. Historically, coldshort iron was considered sufficient for nails.

Phosphorus is not necessarily detrimental to iron. Ancient Near Eastern smiths did not add lime to their furnaces. The absence of calcium oxide in the slag, and the deliberate use of wood with high phosphorus content during the smelting, induces a higher phosphorus content (typically <0.3%) than in modern iron (<0.02–0.03%). Analysis of the Iron Pillar of Delhi gives 0.11% in the iron. The included slag in wrought iron also imparts corrosion resistance.

Antique music wire, manufactured at a time when mass-produced carbon-steels were available, was found to have low carbon and high phosphorus; iron with high phosphorus content, normally causing brittleness when worked cold, was easily drawn into music wires. Although at the time phosphorus was not an easily identified component of iron, it was hypothesized that the type of iron had been rejected for conversion to steel but excelled when tested for drawing ability.

China
During the Han dynasty (202 BC – 220 AD), new iron smelting processes led to the manufacture of new wrought iron implements for use in agriculture, such as the multi-tube seed drill and iron plough. In addition to accidental lumps of low-carbon wrought iron produced by excessive injected air in ancient Chinese cupola furnaces. The ancient Chinese created wrought iron by using the finery forge at least by the 2nd century BC, the earliest specimens of cast and pig iron fined into wrought iron and steel found at the early Han dynasty site at Tieshengguo. Pigott speculates that the finery forge existed in the previous Warring States period (403–221 BC), due to the fact that there are wrought iron items from China dating to that period and there is no documented evidence of the bloomery ever being used in China. The fining process involved liquifying cast iron in a fining hearth and removing carbon from the molten cast iron through oxidation. Wagner writes that in addition to the Han dynasty hearths believed to be fining hearths, there is also pictorial evidence of the fining hearth from a Shandong tomb mural dated 1st to 2nd century AD, as well as a hint of written evidence in the 4th century AD Daoist text Taiping Jing.

Western world

Wrought iron has been used for many centuries, and is the "iron" that is referred to throughout Western history. The other form of iron, cast iron, was in use in China since ancient times but was not introduced into Western Europe until the 15th century; even then, due to its brittleness, it could be used for only a limited number of purposes. Throughout much of the Middle Ages, iron was produced by the direct reduction of ore in manually operated bloomeries, although water power had begun to be employed by 1104.

The raw material produced by all indirect processes is pig iron. It has a high carbon content and as a consequence, it is brittle and cannot be used to make hardware. The osmond process was the first of the indirect processes, developed by 1203, but bloomery production continued in many places. The process depended on the development of the blast furnace, of which medieval examples have been discovered at Lapphyttan, Sweden and in Germany.

The bloomery and osmond processes were gradually replaced from the 15th century by finery processes, of which there were two versions, the German and Walloon. They were in turn replaced from the late 18th century by puddling, with certain variants such as the Swedish Lancashire process. Those, too, are now obsolete, and wrought iron is no longer manufactured commercially.

Bloomery process
Wrought iron was originally produced by a variety of smelting processes, all described today as "bloomeries". Different forms of bloomery were used at different places and times. The bloomery was charged with charcoal and iron ore and then lit. Air was blown in through a tuyere to heat the bloomery to a temperature somewhat below the melting point of iron. In the course of the smelt, slag would melt and run out, and carbon monoxide from the charcoal would reduce the ore to iron, which formed a spongy mass (called a "bloom") containing iron and also molten silicate minerals (slag) from the ore. The iron remained in the solid state. If the bloomery were allowed to become hot enough to melt the iron, carbon would dissolve into it and form pig or cast iron, but that was not the intention. However, the design of a bloomery made it difficult to reach the melting point of iron and also prevented the concentration of carbon monoxide from becoming high.

After smelting was complete, the bloom was removed, and the process could then be started again. It was thus a batch process, rather than a continuous one such as a blast furnace. The bloom had to be forged mechanically to consolidate it and shape it into a bar, expelling slag in the process.

During the Middle Ages, water-power was applied to the process, probably initially for powering bellows, and only later to hammers for forging the blooms. However, while it is certain that water-power was used, the details remain uncertain. That was the culmination of the direct process of ironmaking. It survived in Spain and southern France as Catalan Forges to the mid 19th century, in Austria as the stuckofen to 1775, and near Garstang in England until about 1770;  it was still in use with hot blast in New York in the 1880s. In Japan the last of the old tatara bloomeries used in production of traditional tamahagane steel, mainly used in swordmaking, was extinguished only in 1925, though in the late 20th century the production resumed on a low scale to supply the steel to the artisan swordmakers.

Osmond process
Osmond iron consisted of balls of wrought iron, produced by melting pig iron and catching the droplets on a staff, which was spun in front of a blast of air so as to expose as much of it as possible to the air and oxidise its carbon content. The resultant ball was often forged into bar iron in a hammer mill.

Finery process
In the 15th century, the blast furnace spread into what is now Belgium where it was improved. From there, it spread via the Pays de Bray on the boundary of Normandy and then to the Weald in England. With it, the finery forge spread. Those remelted the pig iron and (in effect) burnt out the carbon, producing a bloom, which was then forged into bar iron. If rod iron was required, a slitting mill was used.

The finery process existed in two slightly different forms. In Great Britain, France, and parts of Sweden, only the Walloon process was used. That employed two different hearths, a finery hearth for finishing the iron and a chafery hearth for reheating it in the course of drawing the bloom out into a bar. The finery always burnt charcoal, but the chafery could be fired with mineral coal, since its impurities would not harm the iron when it was in the solid state. On the other hand, the German process, used in Germany, Russia, and most of Sweden used a single hearth for all stages.

The introduction of coke for use in the blast furnace by Abraham Darby in 1709 (or perhaps others a little earlier) initially had little effect on wrought iron production. Only in the 1750s was coke pig iron used on any significant scale as the feedstock of finery forges. However, charcoal continued to be the fuel for the finery.

Potting and stamping
From the late 1750s, ironmasters began to develop processes for making bar iron without charcoal. There were a number of patented processes for that, which are referred to today as potting and stamping. The earliest were developed by John Wood of Wednesbury and his brother Charles Wood of Low Mill at Egremont, patented in 1763. Another was developed for the Coalbrookdale Company by the Cranage brothers. Another important one was that of John Wright and Joseph Jesson of West Bromwich.

Puddling process

A number of processes for making wrought iron without charcoal were devised as the Industrial Revolution began during the latter half of the 18th century. The most successful of those was puddling, using a puddling furnace (a variety of the reverberatory furnace), which was invented by Henry Cort in 1784. It was later improved by others including Joseph Hall, who was the first to add iron oxide to the charge. In that type of furnace, the metal does not come into contact with the fuel, and so is not contaminated by its impurities. The heat of the combustion products passes over the surface of the puddle and the roof of the furnace reverberates (reflects) the heat onto the metal puddle on the fire bridge of the furnace.

Unless the raw material used is white cast iron, the pig iron or other raw product of the puddling first had to be refined into refined iron, or finers metal. That would be done in a refinery where raw coal was used to remove silicon and convert carbon within the raw material, found in the form of graphite, to a combination with iron called cementite.

In the fully developed process (of Hall), this metal was placed into the hearth of the puddling furnace where it was melted. The hearth was lined with oxidizing agents such as haematite and iron oxide. The mixture was subjected to a strong current of air and stirred with long bars, called puddling bars or rabbles, through working doors. The air, the stirring, and the "boiling" action of the metal helped the oxidizing agents to oxidize the impurities and carbon out of the pig iron. As the impurities oxidize, they formed a molten slag or drifted off as gas, while the remaining iron solidified into spongy wrought iron that floated to the top of the puddle and was fished out of the melt as puddle balls, using puddle bars.

Shingling
There was still some slag left in the puddle balls, so while they were still hot they would be shingled to remove the remaining slag and cinder. That was achieved by forging the balls under a hammer, or by squeezing the bloom in a machine. The material obtained at the end of shingling is known as bloom. The blooms are not useful in that form, so they were rolled into a final product.

Sometimes European ironworks would skip the shingling process completely and roll the puddle balls. The only drawback to that is that the edges of the rough bars were not as well compressed. When the rough bar was reheated, the edges might separate and be lost into the furnace.

Rolling
The bloom was passed through rollers and to produce bars. The bars of wrought iron were of poor quality, called muck bars  or puddle bars. To improve their quality, the bars were cut up, piled and tied together by wires, a process known as faggoting or piling. They were then reheated to a welding state, forge welded, and rolled again into bars. The process could be repeated several times to produce wrought iron of desired quality. Wrought iron that has been rolled multiple times is called merchant bar or merchant iron.

Lancashire process
The advantage of puddling was that it used coal, not charcoal as fuel. However, that was of little advantage in Sweden, which lacked coal. Gustaf Ekman observed charcoal fineries at Ulverston, which were quite different from any in Sweden. After his return to Sweden in the 1830s, he experimented and developed a process similar to puddling but used firewood and charcoal, which was widely adopted in the Bergslagen in the following decades.

Aston process
In 1925, James Aston of the United States developed a process for manufacturing wrought iron quickly and economically. It involved taking molten steel from a Bessemer converter and pouring it into cooler liquid slag. The temperature of the steel is about 1500 °C and the liquid slag is maintained at approximately 1200 °C. The molten steel contains a large amount of dissolved gases so when the liquid steel hit the cooler surfaces of the liquid slag the gases were liberated. The molten steel then froze to yield a spongy mass having a temperature of about 1370 °C. The spongy mass would then be finished by being shingled and rolled as described under puddling (above). Three to four tons could be converted per batch with the method.

Decline
Steel began to replace iron for railroad rails as soon as the Bessemer process for its manufacture was adopted (1865 on). Iron remained dominant for structural applications until the 1880s, because of problems with brittle steel, caused by introduced nitrogen, high carbon, excess phosphorus, or excessive temperature during or too-rapid rolling. By 1890 steel had largely replaced iron for structural applications.

Sheet iron (Armco 99.97% pure iron) had good properties for use in appliances, being well-suited for enamelling and welding, and being rust-resistant.

In the 1960s, the price of steel production was dropping due to recycling, and even using the Aston process, wrought iron production was labor-intensive. It has been estimated that the production of wrought iron is approximately twice as expensive as that of low-carbon steel. In the United States, the last plant closed in 1969. The last in the world was the Atlas Forge of Thomas Walmsley and Sons in Bolton, Great Britain, which closed in 1973. Its 1860s-era equipment was moved to the Blists Hill site of Ironbridge Gorge Museum for preservation. Some wrought iron is still being produced for heritage restoration purposes, but only by recycling scrap.

Properties

The slag inclusions, or stringers, in wrought iron give it properties not found in other forms of ferrous metal. There are approximately 250,000 inclusions per square inch. A fresh fracture shows a clear bluish color with a high silky luster and fibrous appearance.

Wrought iron lacks the carbon content necessary for hardening through heat treatment, but in areas where steel was uncommon or unknown, tools were sometimes cold-worked (hence cold iron) to harden them. An advantage of its low carbon content is its excellent weldability. Furthermore, sheet wrought iron cannot bend as much as steel sheet metal when cold worked. Wrought iron can be melted and cast; however, the product is no longer wrought iron, since the slag stringers characteristic of wrought iron disappear on melting, so the product resembles impure, cast, Bessemer steel. There is no engineering advantage to melting and casting wrought iron, as compared to using cast iron or steel, both of which are cheaper.

Due to the variations in iron ore origin and iron manufacture, wrought iron can be inferior or superior in corrosion resistance, compared to other iron alloys. There are many mechanisms behind its corrosion resistance. Chilton and Evans found that nickel enrichment bands reduce corrosion. They also found that in puddled, forged, and piled iron, the working-over of the metal spread out copper, nickel, and tin impurities that produce electrochemical conditions that slow down corrosion. The slag inclusions have been shown to disperse corrosion to an even film, enabling the iron to resist pitting. Another study has shown that slag inclusions are pathways to corrosion. Other studies show that sulfur in the wrought iron decreases corrosion resistance, while phosphorus increases corrosion resistance. Chloride ions also decrease wrought iron's corrosion resistance.

Wrought iron may be welded in the same manner as mild steel, but the presence of oxide or inclusions will give defective results. The material has a rough surface, so it can hold platings and coatings better than smooth steel. For instance, a galvanic zinc finish applied to wrought iron is approximately 25–40% thicker than the same finish on steel. In Table 1, the chemical composition of wrought iron is compared to that of pig iron and carbon steel. Although it appears that wrought iron and plain carbon steel have similar chemical compositions, that is deceptive. Most of the manganese, sulfur, phosphorus, and silicon in the wrought iron are incorporated into the slag fibers, making wrought iron purer than plain carbon steel.

Amongst its other properties, wrought iron becomes soft at red heat and can be easily forged and forge welded. It can be used to form temporary magnets, but it cannot be magnetized permanently, and is ductile, malleable, and tough.

Ductility
For most purposes, ductility rather than tensile strength is a more important measure of the quality of wrought iron. In tensile testing, the best irons are able to undergo considerable elongation before failure. Higher tensile wrought iron is brittle.

Because of the large number of boiler explosions on steamboats in the early 1800s, the U.S. Congress passed legislation in 1830 which approved funds for correcting the problem. The treasury awarded a $1500 contract to the Franklin Institute to conduct a study. As part of the study, Walter R. Johnson and Benjamin Reeves conducted strength tests on boiler iron using a tester they had built in 1832 based on a design by Lagerhjelm in Sweden. Because of misunderstandings about tensile strength and ductility, their work did little to reduce failures.

The importance of ductility was recognized by some very early in the development of tube boilers, evidenced by Thurston's comment:

"If made of such good iron as the makers claimed to have put into them 'which worked like lead,' they would, as also claimed, when ruptured, open by tearing, and discharge their contents without producing the usual disastrous consequences of a boiler explosion."

Various 19th century investigations of boiler explosions, especially those by insurance companies, found causes to be most commonly the result of operating boilers above the safe pressure range, either to get more power, or due to defective boiler pressure relief valves and difficulties of obtaining reliable indications of pressure and water levels. Poor fabrication was also a common problem. Also, the thickness of the iron in steam drums was low, by modern standards.

By the late 19th century, when metallurgists were able to better understand what properties and processes made good iron, iron in steam engines was being displaced by steel. Also, the old cylindrical boilers with fire tubes were displaced by water tube boilers, which are inherently safer.

Purity
In 2010, Gerry McDonnell demonstrated in England by analysis that a wrought iron bloom, from a traditional smelt, could be worked into 99.7% pure iron with no evidence of carbon. It was found that the stringers common to other wrought irons were not present, thus making it very malleable for the smith to work hot and cold. A commercial source of pure iron is available and is used by smiths as an alternative to traditional wrought iron and other new generation ferrous metals.

Applications
Wrought iron furniture has a long history, dating back to Roman times. There are 13th century wrought iron gates in Westminster Abbey in London, and wrought iron furniture seemed to reach its peak popularity in Britain in the 17th century, during the reign of William III and Mary II. However, cast iron and cheaper steel caused a gradual decline in wrought iron manufacture; the last wrought ironworks in Britain closed in 1974.

It is also used to make home decor items such as baker's racks, wine racks, pot racks, etageres, table bases, desks, gates, beds, candle holders, curtain rods, bars, and bar stools.

The vast majority of wrought iron available today is from reclaimed materials. Old bridges and anchor chains dredged from harbors are major sources. The greater corrosion resistance of wrought iron is due to the siliceous impurities (naturally occurring in iron ore), namely ferrous silicate.

Wrought iron has been used for decades as a generic term across the gate and fencing industry, even though mild steel is used for manufacturing these "wrought iron" gates. This is mainly because of the limited availability of true wrought iron. Steel can also be hot-dip galvanised to prevent corrosion, which cannot be done with wrought iron.

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

title: Wrought iron


text:
Beneventum

Beneventum (Latin for 'good wind') may refer to :

 * Benevento, city in southern Italy
 * Duchy of Benevento
 * Beneventum (Africa), former city and diocese in Roman Africa, now a Latin Catholic titular bishopric
 * Beneventum Plantation House in South Carolina

title: Beneventum


text:
Help:Interlanguage links/Dutch

The Dutch Wikipedia has recently got the facility to use interlanguage links. In the spirit of international cooperation, you may like to check the pages that we have that link to the Dutch Wikipedia, and check that they link back to the English and other Wikipedias. You can do that by following the link to the Dutch article and then adding e.g. (article name) to the article at the bottom.

There was a list here of all the pages we have that link to the Dutch Wikipedia, which you may still examine by checking the history of this page. What remains are several links that do not have a clear companion over on the Dutch Wikipedia, as well as a list of dates that are not yet linked in a correct way. Please help in resolving these last items and don't forget to also transfer any other language links you find here to the corresponding Dutch article (for example, the Main Page is linked to several different languages). (Remember to take the nl=Dutch link out of the list when you copy them over!) Please remove pages from this list when fixed/checked.

The list

 * Add your articles here

 * XBRL_assurance

Problematic links

 * Interstellar cloud and Nebula - link to the same Dutch page.
 * I have looked in the problem. It is on the English side. Those two English pages need to be merged. Or the difference should be indicated a little bit more. In Dutch the title is translated in simple English "Interstellar clouds and Nebula's". Carsrac (talk) 17:44, 10 December 2007 (UTC)

title: Help:Interlanguage links/Dutch


text:
Jejunum

The jejunum is the second part of the small intestine in humans and most higher vertebrates, including mammals, reptiles, and birds. Its lining is specialized for the absorption by enterocytes of small nutrient molecules which have been previously digested by enzymes in the duodenum.

The jejunum lies between the duodenum and the ileum and is considered to start at the suspensory muscle of the duodenum, a location called the duodenojejunal flexure. The division between the jejunum and ileum is not anatomically distinct. In adult humans, the small intestine is usually 6 - 7 m long (post mortem), about two-fifths of which (about 2.5 m) is the jejunum.

Structure
The interior surface of the jejunum—which is exposed to ingested food—is covered in finger–like projections of mucosa, called villi, which increase the surface area of tissue available to absorb nutrients from ingested foodstuffs. The epithelial cells which line these villi have microvilli. The transport of nutrients across epithelial cells through the jejunum and ileum includes the passive transport of sugar fructose and the active transport of amino acids, small peptides, vitamins, and most glucose. The villi in the jejunum are much longer than in the duodenum or ileum.

The pH in the jejunum is usually between 7 and 8 (neutral or slightly alkaline).

The jejunum and the ileum are suspended by mesentery which gives the bowel great mobility within the abdomen. It also contains circular and longitudinal smooth muscle which helps to move food along by a process known as peristalsis.

Histology
The jejunum contains very few Brunner's glands (found in the duodenum) or Peyer's patches (found in the ileum). However, there are a few jejunal lymph nodes suspended in its mesentery. The jejunum has many large circular folds in its submucosa called plicae circulares that increase the surface area for nutrient absorption. The plicae circulares are best developed in the jejunum.

There is no line of demarcation between the jejunum and the ileum. However, there are subtle histological differences:
 * The jejunum has less fat inside its mesentery than the ileum.
 * The jejunum is typically of larger diameter than the ileum.
 * The villi of the jejunum look like long, finger-like projections, and are a histologically identifiable structure.
 * While the length of the entire intestinal tract contains lymphoid tissue, only the ileum has abundant Peyer's patches, which are unencapsulated lymphoid nodules that contain large numbers of lymphocytes and immune cells, like microfold cells.

Function
The lining of the jejunum is specialized for the absorption by enterocytes of small nutrient particles which have been previously digested by enzymes in the duodenum. Once absorbed, nutrients (with the exception of fat, which goes to the lymph) pass from the enterocytes into the enterohepatic circulation and enter the liver via the hepatic portal vein, where the blood is processed.

Other animals
In fish, the divisions of the small intestine are not as clear and the terms middle intestine or mid-gut may be used instead of jejunum.

Etymology
Jejunum is derived from the Latin word jējūnus (iēiūnus), meaning "fasting." It was so called because this part of the small intestine was frequently found to be void of food following death, due to its intensive peristaltic activity relative to the duodenum and ileum.

The Early Modern English adjective jejune is derived from the same root.

title: Jejunum


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Small intestine

The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the pancreatic duct to aid in digestion. The small intestine is about 5.5 m long and folds many times to fit in the abdomen. Although it is longer than the large intestine, it is called the small intestine because it is narrower in diameter.

The small intestine has three distinct regions – the duodenum, jejunum, and ileum. The duodenum, the shortest, is where preparation for absorption through small finger-like protrusions called villi begins. The jejunum is specialized for the absorption through its lining by enterocytes: small nutrient particles which have been previously digested by enzymes in the duodenum. The main function of the ileum is to absorb vitamin B12, bile salts, and whatever products of digestion that were not absorbed by the jejunum.

Size
The length of the small intestine can vary greatly, from as short as 3 m to as long as 10.5 m, also depending on the measuring technique used. The typical length in a living person is 3–5 m. The length depends both on how tall the person is and how the length is measured. Taller people generally have a longer small intestine and measurements are generally longer after death and when the bowel is empty. It is approximately 1.5 cm in diameter in newborns after 35 weeks of gestational age, and 2.5–3 cm in diameter in adults. On abdominal X-rays, the small intestine is considered to be abnormally dilated when the diameter exceeds 3 cm. On CT scans, a diameter of over 2.5 cm is considered abnormally dilated. The surface area of the human small intestinal mucosa, due to enlargement caused by folds, villi and microvilli, averages 30 m2.

Parts

The small intestine is divided into three structural parts.
 * The duodenum is a short structure ranging from 20-25 cm in length, and shaped like a "C". It surrounds the head of the pancreas. It receives gastric chyme from the stomach, together with digestive juices from the pancreas (digestive enzymes) and the liver (bile). The digestive enzymes break down proteins and bile emulsifies fats into micelles. The duodenum contains Brunner's glands, which produce a mucus-rich alkaline secretion containing bicarbonate. These secretions, in combination with bicarbonate from the pancreas, neutralize the stomach acids contained in gastric chyme.
 * The jejunum is the midsection of the small intestine, connecting the duodenum to the ileum. It is about 2.5 m long, and contains the circular folds, and intestinal villi that increase its surface area. Products of digestion (sugars, amino acids, and fatty acids) are absorbed into the bloodstream here. The suspensory muscle of duodenum marks the division between the duodenum and the jejunum.
 * The ileum: The final section of the small intestine. It is about 3 m long, and contains villi similar to the jejunum. It absorbs mainly vitamin B12 and bile acids, as well as any other remaining nutrients. The ileum joins to the cecum of the large intestine at the ileocecal junction.

The jejunum and ileum are suspended in the abdominal cavity by mesentery. The mesentery is part of the peritoneum. Arteries, veins, lymph vessels and nerves travel within the mesentery.

Blood supply
The small intestine receives a blood supply from the celiac trunk and the superior mesenteric artery. These are both branches of the aorta. The duodenum receives blood from the coeliac trunk via the superior pancreaticoduodenal artery and from the superior mesenteric artery via the inferior pancreaticoduodenal artery. These two arteries both have anterior and posterior branches that meet in the midline and anastomose. The jejunum and ileum receive blood from the superior mesenteric artery. Branches of the superior mesenteric artery form a series of arches within the mesentery known as arterial arcades, which may be several layers deep. Straight blood vessels known as vasa recta travel from the arcades closest to the ileum and jejunum to the organs themselves.

Microanatomy
The three sections of the small intestine look similar to each other at a microscopic level, but there are some important differences. The parts of the intestine are as follows:

Gene and protein expression
About 20,000 protein coding genes are expressed in human cells and 70% of these genes are expressed in the normal duodenum. Some 300 of these genes are more specifically expressed in the duodenum with very few genes expressed only in the small intestine. The corresponding specific proteins are expressed in glandular cells of the mucosa, such as fatty acid binding protein FABP6. Most of the more specifically expressed genes in the small intestine are also expressed in the duodenum, for example FABP2 and the DEFA6 protein expressed in secretory granules of Paneth cells.

Development
The small intestine develops from the midgut of the primitive gut tube. By the fifth week of embryological life, the ileum begins to grow longer at a very fast rate, forming a U-shaped fold called the primary intestinal loop. The loop grows so fast in length that it outgrows the abdomen and protrudes through the umbilicus. By week 10, the loop retracts back into the abdomen. Between weeks six and ten the small intestine rotates anticlockwise, as viewed from the front of the embryo. It rotates a further 180 degrees after it has moved back into the abdomen. This process creates the twisted shape of the large intestine.

Function
Food from the stomach is allowed into the duodenum through the pylorus by a muscle called the pyloric sphincter.

Digestion
The small intestine is where most chemical digestion takes place. Many of the digestive enzymes that act in the small intestine are secreted by the pancreas and liver and enter the small intestine via the pancreatic duct. Pancreatic enzymes and bile from the gallbladder enter the small intestine in response to the hormone cholecystokinin, which is produced in the response to the presence of nutrients. Secretin, another hormone produced in the small intestine, causes additional effects on the pancreas, where it promotes the release of bicarbonate into the duodenum in order to neutralize the potentially harmful acid coming from the stomach.

The three major classes of nutrients that undergo digestion are proteins, lipids (fats) and carbohydrates:
 * Proteins are degraded into small peptides and amino acids before absorption. Chemical breakdown begins in the stomach and continues in the small intestine. Proteolytic enzymes, including trypsin and chymotrypsin, are secreted by the pancreas and cleave proteins into smaller peptides. Carboxypeptidase, which is a pancreatic brush border enzyme, splits one amino acid at a time. Aminopeptidase and dipeptidase free the end amino acid products.
 * Lipids (fats) are degraded into fatty acids and glycerol. Pancreatic lipase breaks down triglycerides into free fatty acids and monoglycerides. Pancreatic lipase works with the help of the salts from the bile secreted by the liver and stored in the gall bladder. Bile salts attach to triglycerides to help emulsify them, which aids access by pancreatic lipase. This occurs because the lipase is water-soluble but the fatty triglycerides are hydrophobic and tend to orient towards each other and away from the watery intestinal surroundings. The bile salts emulsify the triglycerides in the watery surroundings until the lipase can break them into the smaller components that are able to enter the villi for absorption.
 * Some carbohydrates are degraded into simple sugars, or monosaccharides (e.g., glucose). Pancreatic amylase breaks down some carbohydrates (notably starch) into oligosaccharides. Other carbohydrates pass undigested into the large intestine for further handling by intestinal bacteria. Brush border enzymes take over from there. The most important brush border enzymes are dextrinase and glucoamylase, which further break down oligosaccharides. Other brush border enzymes are maltase, sucrase and lactase. Lactase is absent in some adult humans and, for them, lactose (a disaccharide), as well as most polysaccharides, is not digested in the small intestine. Some carbohydrates, such as cellulose, are not digested at all, despite being made of multiple glucose units. This is because the cellulose is made out of beta-glucose, making the inter-monosaccharidal bindings different from the ones present in starch, which consists of alpha-glucose. Humans lack the enzyme for splitting the beta-glucose-bonds, something reserved for herbivores and bacteria from the large intestine.

Absorption
Digested food is now able to pass into the blood vessels in the wall of the intestine through either diffusion or active transport. The small intestine is the site where most of the nutrients from ingested food are absorbed. The inner wall, or mucosa, of the small intestine, is lined with intestinal epithelium, a simple columnar epithelium. Structurally, the mucosa is covered in wrinkles or flaps called circular folds, which are considered permanent features in the mucosa. They are distinct from rugae which are considered non-permanent or temporary allowing for distention and contraction. From the circular folds project microscopic finger-like pieces of tissue called villi (Latin for "shaggy hair"). The individual epithelial cells also have finger-like projections known as microvilli. The functions of the circular folds, the villi, and the microvilli are to increase the amount of surface area available for the absorption of nutrients, and to limit the loss of said nutrients to intestinal fauna.

Each villus has a network of capillaries and fine lymphatic vessels called lacteals close to its surface. The epithelial cells of the villi transport nutrients from the lumen of the intestine into these capillaries (amino acids and carbohydrates) and lacteals (lipids). The absorbed substances are transported via the blood vessels to different organs of the body where they are used to build complex substances such as the proteins required by our body. The material that remains undigested and unabsorbed passes into the large intestine.

Absorption of the majority of nutrients takes place in the jejunum, with the following notable exceptions:
 * Iron is absorbed in the duodenum.
 * Folate (Vitamin B9) is absorbed in the duodenum and jejunum.
 * Vitamin B12 and bile salts are absorbed in the terminal ileum. Vitamin B12 will only be absorbed by the ileum after binding to a protein known as intrinsic factor.
 * Water is absorbed by osmosis and lipids by passive diffusion throughout the small intestine.
 * Sodium bicarbonate is absorbed by active transport and glucose and amino acid co-transport
 * Fructose is absorbed by facilitated diffusion.

Immunological
The small intestine supports the body's immune system. The presence of gut flora appears to contribute positively to the host's immune system. Peyer's patches, located within the ileum of the small intestine, are an important part of the digestive tract's local immune system. They are part of the lymphatic system, and provide a site for antigens from potentially harmful bacteria or other microorganisms in the digestive tract to be sampled, and subsequently presented to the immune system.

Clinical significance
The small intestine is a complex organ, and as such, there are a very large number of possible conditions that may affect the function of the small bowel. A few of them are listed below, some of which are common, with up to 10% of people being affected at some time in their lives, while others are vanishingly rare.

 * Small intestine obstruction or obstructive disorders
 * Meconium ileus
 * Paralytic ileus
 * Volvulus
 * Hernia
 * Intussusception
 * Adhesions
 * Obstruction from external pressure
 * Obstruction by masses in the lumen (foreign bodies, bezoar, gallstones)
 * Infectious diseases
 * Giardiasis
 * Ascariasis
 * Tropical sprue
 * Tape worm (Diphyllobothrium latum, Taenia solium, Hymenolepis nana)
 * Hookworm (e.g. Necator americanus, Ancylostoma duodenale)
 * Nematodes (e.g. Ascaris lumbricoides)
 * Other Protozoa (e.g. Cryptosporidium parvum, Cyclospora, Microsporidia, Entamoeba histolytica)
 * Bacterial infections
 * Enterotoxigenic Escherichia coli
 * Salmonella enterica
 * Campylobacter
 * Shigella
 * Yersinia
 * Clostridium difficile (antibiotic-associated colitis, Pseudomembranous colitis)
 * Mycobacterium (Mycobacterium avium paratuberculosis, disseminated Mycobacterium tuberculosis)
 * Whipple's disease
 * Vibrio (cholera)
 * Enteric (typhoid) fever (Salmonella enterica var. typhii) and paratyphoid fever
 * Bacillus cereus
 * Clostridium perfringens (gas gangrene)
 * Viral infections
 * Rotavirus
 * Norovirus
 * Astrovirus
 * Adenovirus
 * Calicivirus
 * Neoplasms (cancers)
 * Adenocarcinoma
 * Carcinoid
 * Gastrointestinal stromal tumor (GIST)
 * Lymphoma
 * Sarcoma
 * Leiomyoma
 * Metastatic tumors, especially SCLC or melanoma
 * Small intestine cancer
 * Developmental, congenital or genetic conditions
 * Duodenal (intestinal) atresia
 * Hirschsprung's disease
 * Meckel's diverticulum
 * Pyloric stenosis
 * Pancreas divisum
 * Ectopic pancreas
 * Enteric duplication cyst
 * Situs inversus
 * Cystic fibrosis
 * Malrotation
 * Persistent urachus
 * Omphalocele
 * Gastroschisis
 * Disaccharidase (lactase) deficiencies
 * Primary bile acid malabsorption
 * Gardner syndrome
 * Familial adenomatous polyposis syndrome (FAP)
 * Other conditions
 * Crohn's disease, and the more general inflammatory bowel disease
 * Typhlitis (neutropenic colitis in the immunosuppressed
 * Coeliac disease (sprue or non-tropical sprue)
 * Mesenteric ischemia
 * Embolus or thrombus of the superior mesenteric artery or the superior mesenteric vein
 * Arteriovenous malformation
 * Gastric dumping syndrome
 * Irritable bowel syndrome
 * Duodenal (peptic) ulcers
 * Gastrointestinal perforation
 * Hyperthyroidism
 * Diverticulitis
 * Radiation enterocolitis
 * Mesenteric cysts
 * Peritoneal Infection
 * Sclerosing retroperitonitis
 * Small intestinal bacterial overgrowth
 * Endometriosis

Other animals
The small intestine is found in all tetrapods and also in teleosts, although its form and length vary enormously between species. In teleosts, it is relatively short, typically around one and a half times the length of the fish's body. It commonly has a number of pyloric caeca, small pouch-like structures along its length that help to increase the overall surface area of the organ for digesting food. There is no ileocaecal valve in teleosts, with the boundary between the small intestine and the rectum being marked only by the end of the digestive epithelium.

In tetrapods, the ileocaecal valve is always present, opening into the colon. The length of the small intestine is typically longer in tetrapods than in teleosts, but is especially so in herbivores, as well as in mammals and birds, which have a higher metabolic rate than amphibians or reptiles. The lining of the small intestine includes microscopic folds to increase its surface area in all vertebrates, but only in mammals do these develop into true villi.

The boundaries between the duodenum, jejunum, and ileum are somewhat vague even in humans, and such distinctions are either ignored when discussing the anatomy of other animals, or are essentially arbitrary.

There is no small intestine as such in non-teleost fish, such as sharks, sturgeons, and lungfish. Instead, the digestive part of the gut forms a spiral intestine, connecting the stomach to the rectum. In this type of gut, the intestine itself is relatively straight but has a long fold running along the inner surface in a spiral fashion, sometimes for dozens of turns. This valve greatly increases both the surface area and the effective length of the intestine. The lining of the spiral intestine is similar to that of the small intestine in teleosts and non-mammalian tetrapods.

In lampreys, the spiral valve is extremely small, possibly because their diet requires little digestion. Hagfish have no spiral valve at all, with digestion occurring for almost the entire length of the intestine, which is not subdivided into different regions.

Society and culture
In traditional Chinese medicine, the small intestine is a yang organ.

title: Small intestine


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Appendix (anatomy)

The appendix (: appendices or appendixes; also vermiform appendix; cecal (or caecal, cæcal) appendix; vermix; or vermiform process) is a finger-like, blind-ended tube connected to the cecum, from which it develops in the embryo.

The cecum is a pouch-like structure of the large intestine, located at the junction of the small and the large intestines. The term "vermiform" comes from Latin and means "worm-shaped". The appendix was once considered a vestigial organ, but this view has changed since the early 2000s. Research suggests that the appendix may serve an important purpose as a reservoir for beneficial gut bacteria.

Structure
The human appendix averages 9 cm in length, ranging from 5 to 35 cm. The diameter of the appendix is 6 mm, and more than 6 mm is considered a thickened or inflamed appendix. The longest appendix ever removed was 26 cm long. The appendix is usually located in the lower right quadrant of the abdomen, near the right hip bone. The base of the appendix is located 2 cm beneath the ileocecal valve that separates the large intestine from the small intestine. Its position within the abdomen corresponds to a point on the surface known as McBurney's point.

The appendix is connected to the mesentery in the lower region of the ileum, by a short region of the mesocolon known as the mesoappendix.

Variation
Some identical twins—known as mirror image twins—can have a mirror-imaged anatomy, a congenital condition with the appendix located in the lower left quadrant of the abdomen instead of the lower right. Intestinal malrotation may also cause displacement of the appendix to the left side.

While the base of the appendix is typically located 2 cm below the ileocecal valve, the tip of the appendix can be variably located—in the pelvis, outside the peritoneum or behind the cecum. The prevalence of the different positions varies amongst populations with the retrocecal position being most common in Ghana and Sudan, with 67.3% and 58.3% occurrence respectively, in comparison to Iran and Bosnia where the pelvic position is most common, with 55.8% and 57.7% occurrence respectively.

In very rare cases, the appendix may not be present at all (laparotomies for suspected appendicitis have given a frequency of 1 in 100,000).

Sometimes there is a semi-circular fold of mucous membrane at the opening of the appendix. This valve of the vermiform appendix is also called Gerlach's valve.

Maintaining gut flora

Although it has been long accepted that the immune tissue surrounding the appendix and elsewhere in the gut—called gut-associated lymphoid tissue—carries out a number of important functions, explanations were lacking for the distinctive shape of the appendix and its apparent lack of specific importance and function as judged by an absence of side effects following its removal. Therefore, the notion that the appendix is only vestigial became widely held.

William Parker, Randy Bollinger, and colleagues at Duke University proposed in 2007 that the appendix serves as a haven for useful bacteria when illness flushes the bacteria from the rest of the intestines. This proposition is based on an understanding that emerged by the early 2000s of how the immune system supports the growth of beneficial intestinal bacteria, in combination with many well-known features of the appendix, including its architecture, its location just below the normal one-way flow of food and germs in the large intestine, and its association with copious amounts of immune tissue.

Research performed at Winthrop–University Hospital showed that individuals without an appendix were four times as likely to have a recurrence of Clostridium difficile colitis. The appendix, therefore, may act as a "safe house" for beneficial bacteria. This reservoir of bacteria could then serve to repopulate the gut flora in the digestive system following a bout of dysentery or cholera or to boost it following a milder gastrointestinal illness.

Immune and lymphatic systems
The appendix has been identified as an important component of mammalian mucosal immune function, particularly B cell-mediated immune responses and extrathymically derived T cells. This structure helps in the proper movement and removal of waste matter in the digestive system, contains lymphatic vessels that regulate pathogens, and lastly, might even produce early defences that prevent deadly diseases. Additionally, it is thought that this may provide more immune defences from invading pathogens and getting the lymphatic system's B and T cells to fight the viruses and bacteria that infect that portion of the bowel and training them so that immune responses are targeted and more able to reliably and less dangerously fight off pathogens. In addition, there are different immune cells called innate lymphoid cells that function in the gut in order to help the appendix maintain digestive health.

Research also shows a positive correlation between the existence of the appendix and the concentration of cecal lymphoid tissue, which supports the suggestion that not only does the appendix evolve as a complex with the cecum but also has major immune benefits.

Clinical significance

Common diseases of the appendix (in humans) are appendicitis and carcinoid tumors (appendiceal carcinoid). Appendix cancer accounts for about 1 in 200 of all gastrointestinal malignancies. In rare cases, adenomas are also present.

Appendicitis
Appendicitis is a condition characterized by inflammation of the appendix. Pain often begins in the center of the abdomen, corresponding to the appendix's development as part of the embryonic midgut. This pain is typically a dull, poorly localized, visceral pain.

As the inflammation progresses, the pain begins to localize more clearly to the right lower quadrant, as the peritoneum becomes inflamed. This peritoneal inflammation, or peritonitis, results in rebound tenderness (pain upon removal of pressure rather than application of pressure). In particular, it presents at McBurney's point, 1/3 of the way along a line drawn from the anterior superior iliac spine to the umbilicus. Typically, point (skin) pain is not present until the parietal peritoneum is inflamed, as well. Fever and an immune system response are also characteristic of appendicitis. Other signs and symptoms may include nausea and vomiting, low-grade fever that may get worse, constipation or diarrhea, abdominal bloating, or flatulence.

Appendicitis usually requires the removal of the inflamed appendix, in an appendectomy either by laparotomy or laparoscopy. Untreated, the appendix may rupture, leading to peritonitis, followed by shock, and, if still untreated, death.

Surgery
The surgical removal of the appendix is called an appendectomy. This removal is normally performed as an emergency procedure when the patient is suffering from acute appendicitis. In the absence of surgical facilities, intravenous antibiotics are used to delay or avoid the onset of sepsis. In some cases, the appendicitis resolves completely; more often, an inflammatory mass forms around the appendix. This is a relative contraindication to surgery.

The appendix is also used for the construction of an efferent urinary conduit, in an operation known as the Mitrofanoff procedure, in people with a neurogenic bladder.

The appendix is also used as a means to access the colon in children with paralysed bowels or major rectal sphincter problems. The appendix is brought out to the skin surface and the child/parent can then attach a catheter and easily wash out the colon (via normal defaecation) using an appropriate solution.

History
Charles Darwin suggested that the appendix was mainly used by earlier hominids for digesting fibrous vegetation, then evolved to take on a new purpose over time. The very long cecum of some herbivorous animals, such as in the horse or the koala, appears to support this hypothesis. The koala's cecum enables it to host bacteria that specifically help to break down cellulose. Human ancestors may have also relied upon this system when they lived on a diet rich in foliage.

As people began to eat more easily digested foods, they may have become less reliant on cellulose-rich plants for energy. As the cecum became less necessary for digestion, mutations that were previously deleterious (and would have hindered evolutionary progress) were no longer important, so the mutations survived. It is suggested that these alleles became more frequent and the cecum continued to shrink. After millions of years, the once-necessary cecum degraded to be the appendix of modern humans.

Dr. Heather F. Smith of Midwestern University and colleagues explained:

Recently ... improved understanding of gut immunity has merged with current thinking in biological and medical science, pointing to an apparent function of the mammalian cecal appendix as a safe-house for symbiotic gut microbes, preserving the flora during times of gastrointestinal infection in societies without modern medicine. This function is potentially a selective force for the evolution and maintenance of the appendix. Three morphotypes of cecal-appendices can be described among mammals based primarily on the shape of the cecum: a distinct appendix branching from a rounded or sac-like cecum (as in many primate species), an appendix located at the apex of a long and voluminous cecum (as in the rabbit, greater glider and Cape dune mole rat), and an appendix in the absence of a pronounced cecum (as in the wombat). In addition, long narrow appendix-like structures are found in mammals that either lack an apparent cecum (as in monotremes) or lack a distinct junction between the cecum and appendix-like structure (as in the koala). A cecal appendix has evolved independently at least twice, and apparently represents yet another example of convergence in morphology between Australian marsupials and placentals in the rest of the world. Although the appendix has apparently been lost by numerous species, it has also been maintained for more than 80 million years in at least one clade.

In a 2013 paper, the appendix was found to have independently evolved in different animals at least 32 times (and perhaps as many as 38 times) and to have been lost no more than six times over the course of history. A more recent study using similar methods on an updated database yielded similar, though less spectacular results, with at least 29 gains and at the most 12 losses (all of which were ambiguous), and this is still significantly asymmetrical.

This suggests that the cecal appendix has a selective advantage in many situations and argues strongly against its vestigial nature. Given that this organ may have a selective advantage in numerous situations, it appears to be associated with greater maximal longevity, for a given body mass. For example, in a 2023 study, the protective functions conferred against diarrhea were observed in young primates. This complex evolutionary history of the appendix, along with a great heterogeneity in its evolutionary rate in various taxa, suggests that it is a recurrent trait.

Such a function may be useful in a culture lacking modern sanitation and healthcare practice, where diarrhea may be prevalent. Current epidemiological data on the cause of death in developing countries collected by the World Health Organization in 2001 show that acute diarrhea is now the fourth leading cause of disease-related death in developing countries (data summarized by the Bill and Melinda Gates Foundation). Two of the other leading causes of death are expected to have exerted limited or no selection pressure.

title: Appendix (anatomy)