…and this is a 
What use is an appendix?
Category: Creationism • Science
Posted on: February 18, 2007 2:41 PM, by PZ Myers
Here's an excellent and useful summary of the appendix from a surgeon's perspective. Creationists dislike the idea that we bear useless organs, remnants of past function that are non-functional or even hazardous to our health; they make up stories about the importance of these vestiges. Sid Schwab has cut out a lot of appendices, and backs up its non-utility with evidence.
The study I cited most often to my patients when asked about adverse consequences of appendectomy is one done by the Mayo Clinic: they studied records of thousands of patients who'd had appendectomy, and compared them with equal thousands who hadn't. (Back in the day, it was very common during any abdominal operation to remove the appendix. Like flicking a bug off your shoulder. No extra charge: just did it to prevent further problems: took an extra couple of minutes, is all.) The groups were statistically similar in every way other than presence of the worm. There were no differences in incidence of any disease. It's as convincing as it gets, given the impossibility of doing a prospective double-blind study.
I have a personal interest in this: I was nearly killed by my appendix at the age of 9, and had it removed. I haven't missed it since.
Comments
This demonstrates the careless arrogance of surgeons better than it does the redundancy of the appendix.
Posted by: Caledonian | February 18, 2007 3:01 PM
I, too, haven't missed my appendix since it tried to kill me.
Of course, appendices could simply be a test for our faith in God. Or they could have been put there by Satan. Or our bodies are imperfect because of original sin.
There are thousands of things you can make up to explain creationism. Since everything about it is fiction, why not throw in some more fiction to make it internally consistent?
Posted by: Phronk | February 18, 2007 3:02 PM
I thought the appendix was for listing the mathematical derivations used in the main text?
Badoom-ching! Thank you, thank you, I'll be here all week. . . .
Posted by: Blake Stacey | February 18, 2007 3:04 PM
Wait.. I am sure I read something recently implying that the appendix "still" has some things it does in the immune system, but that the actual benefit gained from it is highly redundant and usually far outweighed by the danger it posses. Something about you being slightly more likely to develop new allergies or something without it, but only at an early age...
Yep:
Sorry, but a surgeon, as sadly is often the case, *practices* medicine, they don't generally study or research it, unless it involved how to chop something up. Its also why you are more likely to find doctors mistreating people with the "side effects" of a drug in the hope that it will have some positive effect, then taking any immediate sign of improvement as proof of the efficacy of the treatment, than you find them making careful "scientific" tests with double blind experiments, etc. Yes, until recently the appendix was assumed to be useless. And, in an adult, it very well may be, as the next sentence in the article I quoted states: "In adults, the appendix is best known for its tendency to become inflamed, necessitating surgical removal."
http://www.sciam.com/askexpert_question.cfm?articleID=0002A56A-62A5-1C72-9EB7809EC588F2D7&catID=3&topicID=3
Still doesn't prove the lunatic assertions that some creationists are bound to come up with, though it just gives them another, "See, scientists claim to know everything, but backpeddle when they are proven wrong!", BS argument.
Posted by: Kagehi | February 18, 2007 3:05 PM
So, why is it not routine to remove the appendix anytime it is accessible in an abdominal operation thes days? I don't mean going out of your way or risking other tissues, I mean when it is a simple thing? And is it usually a simple thing, for most procedures, even the increasing number done with scopes?
If my belly is asleep, and I am asleep, and you are rooting around in there, I say go for it. Am I wrong? Sid? Orac? Anyone?
Posted by: Skeptyk | February 18, 2007 3:06 PM
The author also doesn't know nearly as much about the appendix as he should. He suggests that saving the lives of people with ruptured or inflamed appendices has helped keep them around. It's quite the opposite - once the appendix drops below a certain size, the chance that it will become clogged and inflamed increase dramatically. It's the reason we still have this relic of the digestive tract. Recombination causes the useless organ to slowly degenerate over time, up to the point where individuals with highly degenerate organs become more likely to die.
Saving the lives of people with appendicitis would eventually cause the organ to disappear entirely.
Posted by: Caledonian | February 18, 2007 3:07 PM
Skeptyk:
I asked the same question over at Surgeonsblog, so maybe the author of the original post will reply.
Posted by: Blake Stacey | February 18, 2007 3:09 PM
I've always wanted to have mine yanked, but no one's ever had a reason to open my my abdomen. The closest I've come is having a benign tumor removed from my tummy, but it was extraperitoneal.
I don't like having to wonder if my appendix is inflamed every time I have severe abdominal pain and nausea.
Posted by: David Livesay | February 18, 2007 3:10 PM
Among other things, I believe it became frowned upon for surgeons to start 'fixing' healthy tissue unrelated to whatever reason they were operating, and the advent of science-based medicine meant that some pressure to avoid interventions that hadn't been studied yet.
For all the surgeons knew, removing the appendix would have led to a higher risk of some unknown condition. Getting lucky is not a defense.
Last comment, and I'll be done here (I promise): the appendix is a superb example of how evolutionary forces can be complex and counterintuitive, yet is utterly incompatible with the idea that we were designed by an intelligent force. IDists, in their arrogance and ignorance, are drawing people's attention to the prime evidence against their positions. Ha!
Posted by: Caledonian | February 18, 2007 3:12 PM
Okay, would it be "the careless arrogance of surgeons" to add a specific line to the informed consent about appendices?
And how do you know that folks "back in the day" were NOT informed? Wasn't it routine to tell a patient, "and while we are there, we'll take your appendix out"? Is Caledonian just assuming the patients were not told?
Posted by: Skeptyk | February 18, 2007 3:15 PM
Wasn't it common at one time for people going to Antarctica to have their appendices removed beforehand just so it wouldn't rupture?
There's a tangentially related case to this; a severely mentally retarded girl whose parents have done a lot of modifications, including appendix removal. Brings up lots of other questions, but they took out the appendix precisely because if anything ever happened, she couldn't tell them what was wrong. the ashley treatment
Posted by: Carlie | February 18, 2007 3:41 PM
Evolution question: We don't eat tough grasses, and our appendix doesnt work. Is the appendix vestigeal and useless because our biology doesn't have us eating the things the appendix was used to help digest? Or did a dysfunctional appendix direct our evolution into scavengers since we couldnt eat those things anymore?
I had appendicitis at 9 too.
Posted by: Karey | February 18, 2007 3:48 PM
Jane Goodall had hers removed before going to Africa. I don't know whether any astronauts have had preventive appendectomies, but I bet future ones going to Mars will.
Posted by: Jane Shevtsov | February 18, 2007 3:50 PM
An "incidental appendectomy" (which is what we call it when we remove a normal appendix while doing a different abdominal operation) is not without potential complications and may result in a slightly longer length of stay. (It's a real bummer if a patient on whom you do, say a ventral hernia repair, develops a pelvic abscess or a colonic fistula from the appendiceal stump when you didn't have a medical indication to remove the appendix. Surgeons picture themselve being questioned by a not very friendly lawyer about why they decided to do an "unnecessary procedure" that resulted in a nasty complication.) However, in reality, recent studies show that the increased risk of complications from incidental appendectomy is small, and there are still advocates of the generous use of incidental appendectomies. It may be that the pendulum has swung too far in the other direction (from doing them all the time to almost never doing them). And, of course, there is the matter of informed consent; you can't just remove the appendix without getting consent for it beforehand. Finally, to be blunt, another reason it's not routinely done is probably partially because insurance companies won't pay for it.
In reality, these days, the only times we tend to do incidental appendectomies are in younger patients, because they have more years ahead in which to develop appendicitis or for patients where we have made a right lower quadrant incision that looks like an appendectomy scar. In this latter case, if we leave the appendix behind, it could confuse the diagnosis if the patient ever gets right lower quadrant pain again. The surgeon might assume that the patient no longer has an appendix if an apparent appendectomy scar is there.
Posted by: Orac | February 18, 2007 3:55 PM
the advent of science-based medicine meant that some pressure to avoid interventions that hadn't been studied yet.
Not to mention the proliferation of baseless malpractice lawsuits.
I had appendicitis at 9 too.
I'm beginning to feel left out. I'm 36 and still have my appendix and my tonsils.
Posted by: Tukla in Iowa | February 18, 2007 3:55 PM
Jane Shevtsov:
Those astronauts had better get their vestigial organs removed, or else we'll face the same problem they had in Rama II. Seriously, people, science fiction is there for you to learn from!
(-;
Posted by: Blake Stacey | February 18, 2007 3:56 PM
Mine tried to kill me the day I took the 11+, an exam that used to to be taken in Britain to decide if you go to grammar school or not. I survived, my appendix didn't and I passed the exam as well!
Posted by: Thony C. | February 18, 2007 3:57 PM
Posted by: David Livesay | February 18, 2007 4:04 PM
Thanks for the elaboration, Orac!
Posted by: Blake Stacey | February 18, 2007 4:06 PM
David, it won't work. I've wished really hard for some people to go away (but they keep on getting re-elected). Maybe it only works if it's something that you could spend money on.
Posted by: DrBadger | February 18, 2007 4:07 PM
Nice to have it confirmed that I won't be missing my appendix (which up and busted on me, about 11 years ago). Of course, I then went and developed diverticular disease, just so I can do it all over again if I want (or don't want).
Posted by: Steve Watson | February 18, 2007 4:11 PM
I want to repeat the question that Karey asked:
"Evolution question: We don't eat tough grasses, and our appendix doesnt work. Is the appendix vestigeal and useless because our biology doesn't have us eating the things the appendix was used to help digest? Or did a dysfunctional appendix direct our evolution into scavengers since we couldnt eat those things anymore?"
Is it known what use the appendix had? Do any memebers of the ape/monkey family have appendices?
This blog, and Orac's, is about defending Ev against ID, isn't it? So, give us a defense. What did the appendix do and why has it stopped being useful?
(And, by the way, I am a staunch defender of Ev, not an ID troll).
Posted by: Karl | February 18, 2007 4:18 PM
(I just posted this over at "Surgeon's Blog", but thought there might be interest here, too).
I believe that you need to be careful not to talk up appendectomy too much. Obviously, if it is indicated, the procedure should be performed, but it definitely shouldn't be performed "just in case".
My father carried out an epidemiological study some years ago (in the 1970s) on the survivability of appendectomies in West Germany vs. other germanophone countries, as well as the US and the UK (iirc). What he discovered was that West Germany had something like 10x the mortality rate (per-capita) due to appendectomies that the US had. As it turned out, this was because West German surgeons had a "cut first, ask questions later" philosophy regarding abdominal pain.
The point was, it's better to perform no operation than to perform an unnecessary one.
Incidentally, it may be worthwhile noting that a significant number of people who died due to their appendectomy had their deaths labeled as something unrelated, as they may have occurred some time (a week or more) after their operation. These deaths would not have been counted in the mentioned studies.
I believe (but I'm not quite sure) that said study is presented in the papers that are identified in the PubMed index as 820981 and 5562429 (although there may be others, too).
Posted by: mysh | February 18, 2007 4:39 PM
The human appendix corresponds to the "caecum" of many herbivorous mammals. The caecum is used to store digested food that was travelling down the small intestines for later, and or further digestion. In some species, like squirrels, and some monkeys, the caecum serves as a larder, storing food in case of times of hardship. In other species, like koalas, leaf-eating monkeys and horses, the caecum stores digested food so that they can stay in the gut longer, thereby prolonging bacterial fermentation, thus liberating more nutrients.
Posted by: Stanton | February 18, 2007 4:48 PM
I have no interest in buoying a creationist argument (I'm an evolutionary biologist and my dad's a gastoenterologist), BUT...
That the appendix seems to have no function in adults doesn't mean that it doesn't play an important role at other developmental stages. Recent work suggests that it's used as a lymphoid organ during foetal development, exposing immune cells to foreign antigens, etc.
http://www.newscientist.com/backpage.ns?id=lw968
As far as I know, however, it's still not clear whether the human appendix has always had this function, or whether the structure's been subsequently co-opted.
PZ, I thought that you were an evo-devo biologist ;)
Posted by: JVC | February 18, 2007 4:52 PM
Reading through this thread reminds me of going to get the oil changed. "Oh, hey, while you're in there, can you replace the oil filter and the windshield wiper blades?"
Except, you know, with organs. Seems to me as long as you're getting opened up, might as well take care of everything. Who wants to go through abdominal surgery more than once? I know similar reasoning led me to have all my wisdom teeth out at the same time. Sure, I was in pain and eating oatmeal and pudding for two weeks, but it's better than going through it twice.
Incidentally, I'm 23 and still have my appendix and tonsils.
Posted by: Tom Foss | February 18, 2007 5:20 PM
JVC,
I agree that the appendix's function in the developing immune system cannot be so cavalierly discounted.
I am a Pathologist and have seen thousands of them, inflamed and normal. I always found it interesting how childhood acute leukemic cells will localize in the appendix and not other parts of the GI tract. Since many types of ALL consist of lymphocytes expressing immature phenotypes, it isn't too much of a stretch to speculate that the appendix could be a haven for lymphocytic maturation.
Oh yeah, pinworms also love to live in the appendix, which is really cool microscopically. I have the world's best job, by the way.
Posted by: Dwimr | February 18, 2007 5:29 PM
Not being qualified to comment on the issue at hand, I offer you this anecdote instead:
My dad had to have an emergency appendicitus operation in Papua New Guinea a number of years ago. PNG medicine back then was a bit like Russian roulette; some doctors were excellent, others hopeless. The one my dad got was a brand new one. Noone knew if he was any good.
The operation went fine, and here I am.
Posted by: Markk | February 18, 2007 5:33 PM
I bet if we were all in the same room we'd be comparing appendix scars by now.
Posted by: Karey | February 18, 2007 6:13 PM
Thanks, Orac and all, for the info.
"Incidental Appendectomy" Rhythmic, flowing, nice name for a band.
Posted by: Skeptyk | February 18, 2007 6:18 PM
As someone who had THE appendectomy from hell, I would like to weigh in.
In 1987, after eating a plate of green enchiladas at La Cucaracha (St. Paul) for lunch, I felt sick to my stomach. I assumed food poisoning and put myself to bed. I laid there for 2 days, hoping to feel better and finally went to the doctor. They checked me into the hospital (the now-defunct Mount Sinai, Mpls.) and started doing tests.
I got tested for everything from ectopic pregnancy to salmonella and the tests came up negative. They did CAT scans, etc. and after 2 days decided to do "exploratory" surgery. The surgeons found my appendix had burst and my abdomen was filled with infection. They said if my body hadn't done such a good job of walling it off, I would have been dead.
However, even after surgery, my temperature did not go down and I was in intensive care. The doctors said they would have to operate again and asked if I wanted them to do it or go down to Mayo Clinic. Having already gone through a botched diagnosis and surgery, it was an easy answer. "Mayo!"
The ambulance ride down to Rochester was so painful, I would break into tears days later just thinking about it. At Mayo I had a second operation to find the hidden abscesses and finally recovered.
I learned that during my ordeal, a health-food fanatic coworker had been sharing his view around the office that appendicitis was a condition caused entirely by diet. Both my parents had appendectomies in their 30's, something this coworker did not know, but his ignorance didn't stop him from blaming me for my 2 weeks of agony.
I'll do another post sometime about my gall bladder...
Posted by: Sonja | February 18, 2007 6:26 PM
Knew a girl in seventh grade whose appendix killed her. That was the worst funeral I've ever been to. Have wanted mine out ever since, but haven't had an opportunity.
Posted by: Chinchillazilla | February 18, 2007 6:47 PM
Sonja:...a health-food fanatic coworker... sharing his view ...that appendicitis was a condition caused entirely by diet...his ignorance didn't stop him from blaming me for my 2 weeks of agony.
Ah, well, whether it was your diet or whom you chose for parents or repressing your true path, as long as you know its your fault, YOU manifested the appendicitis. (Don't think you can pin it on something out of your control, like Mercury in retrograde or something.)
Posted by: Skeptyk | February 18, 2007 6:49 PM
PZ-
Creationists would argue that your case is evidence for the great virtue of the appendix. Sadly (for them) the virtue was thwarted by intervention of modern medicine.
Posted by: Les lane | February 18, 2007 6:50 PM
JVC wrote:
Why would there be foreign antigens in the appendix during fetal development?
I checked the New Scientist page to see if they didn't mean something else but "Kathleen James, Chicago, Illinois" does seem to be a bit confused:
This is either very vaguely written or just wrong. I don't know how this thing "The Last Word" works, are the answers provided by laymen or scientists?
Posted by: windy | February 18, 2007 7:06 PM
Skeptyk, so you believe people can modify their behavior and prevent appendicitis?
You should appear on TV infommercials with Kevin Trudeau!
Posted by: Sonja | February 18, 2007 7:11 PM
Christopher Wanjek's "Bad Medicine," Chapter 6, certainly addresses the issue of the uselessness of the appendix - that is to say, it does do something. In primates, it helps difficult digestion and in humans, it makes endochrine cells in fetuses, and after birth, functions as a lymphoid organ, helping to create one variety of white blood cells. Eventually, in adulthood, it stops doing the work. The point is you can live without it, but not necessary and useless are two different things.
Posted by: John | February 18, 2007 7:24 PM
Mine didn't try to kill me until I was 11. I haven't missed the little sucker in the slightest.
Posted by: Russell Blackford | February 18, 2007 8:37 PM
"And how do you know that folks "back in the day" were NOT informed? Wasn't it routine to tell a patient, "and while we are there, we'll take your appendix out"? Is Caledonian just assuming the patients were not told?"
They didn't ask me. (And I hate that something that happened to me as an adult is considered ancient history.)
It was December 1986, emergency surgery for a bowel obstruction caused by adhesions from emergency surgery 2 years before after gettign hit by a truck.
(Incidentally, you want hospital horror stories, then my "3 days in the hospital with a total bowel obstruction and no pain meds before diagnosis" story is almost as good as my "nurse removed my catheter but forgot to first deflate the little balloon" story.)
Posted by: craig | February 18, 2007 8:45 PM
No, the appendix merely gets in the way. The immune cells don't belong to the appendix at all. They are busy migrating while developing and some have the misfortune to get lodged there.
However, they'd do their job (ie not that of the appendix!) much better if the appendix hadn't been in the way at all during development - as per the sibling cells which get away or never go near. Unfortunately, foetal surgery, to remove the appendix soon enough, isn't exactly practical. So it remains a liability.
Posted by: SEF | February 18, 2007 9:21 PM
On the thought of people in "out the way places needing medical attention", I find this story fascinating: http://www.history.navy.mil/faqs/faq87-3a1.htm
Tea strainers and spoons....amazing...
Posted by: Hawkeye | February 18, 2007 9:39 PM
JVC listed that newscientist Q&A note where ONE of the responders talks about potential immunological function in fetal and adolescent development.
before anybody else continues to cite that (and it IS the only thing I've seen cited), do recall that:
1. It was a Q&A, NOT an actual article.
2. the person who responded thusly did not provide any supporting references whatsoever.
so I'd say take the "reasonableness" of what that person said with a grain of salt; DO attempt to search the pubmed lit. database to see if there in fact is legit support for saying such things, and above all - DON'T fucking quote a Q&A session from New Scientist as if it was primary literature on point, either find the primary source, or don't even bother to mention it.
Posted by: Ichthyic | February 18, 2007 10:08 PM
Heh, Hawkeye! I was delivered (by an MD) in the late 40's in China with my dad, tea strainer and can of ether in hand, serving as the anesthesist.
But I still have my appendix.
Posted by: Coragyps | February 18, 2007 10:19 PM
Right... one of today's Har Mar posters was on Vestigial Organs. Or, more exactly, on the claim that evolutionist require vestigial organs in order for "evolution to be true" ...
Of course, the appendix does have a use. It is part of a sort of developmental template that is differentially modified across different species depending on the (designed by natural selection) demands of the digestive system. Thus it also serves an important use as part of the evidence for evolution via comparative anatomy.
Posted by: Greg Laden | February 18, 2007 11:44 PM
I concur, Caledonian: the appendix is indeed a stumper for the IDevotees, not to mention a nice demonstration of evolution's subtleties.
However, I'm not entirely sure that saving "the lives of people with appendicitis would eventually cause the organ to disappear entirely." That sounds a bit like the old 'use and disuse' to me, and if that were the case, we would expect the incidence of those with acute appendicitis to decline (all things being equal, of course) IF the propensity for acute appendicitis had a genetic basis. Since, as you suggested, the relative size of the organ has something to do with that, the latter seems likely.
Some studies prior to the 1990's reported such a decline. However, a more recent one raised serious doubts such a decline, as noted here:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=11244262
These results, coupled with a number of papers showing much higher incidence of acute appendicitis in developing countries, suggest that much of the apparent 'decline' in Western nations over the last 50 years is due to the availability of antibiotics.
It will be interesting to see what the genetic switches are that govern the formation and size of the veriformera, and the degree of variability in such switches. This study, below, suggests significant variation between isolated populations:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=2720346&query_hl=5&itool=pubmed_docsum
Like I said, it's an interesting case...SH
Posted by: Scott Hatfield | February 18, 2007 11:56 PM
"Those astronauts had better get their vestigial organs removed, or else we'll face the same problem they had in Rama II."
Funny you'd mention Clarke, because I developed appendicitis while watching 2001. Incidentally, I still like 2001, but I completely lost my stomach for Hawaiian food. (I was at a graduation luau that afternoon.)
I was 16 or so at the time and damned near got myself killed because I waited something like five days before going to the ER. I stupidly assumed I had stomach flu and tried to ignore the pain. I ended up with a ruptured appendix and a truly epic case of peritonitis, the sum of which, combined with the surgery, left me unable to really walk for at least two weeks afterward. There was some additional craziness in the next couple of months that I won't get into because it's way TMI for commenting on someone else's blog, but the short version is that one of the stitches they placed in my abdominal muscle was rejected and triggered an immune reaction that prevented the incision from properly closing...
All that said, There's No Such Thing as Minor Surgery, so I still wouldn't advocate ripping out appendices during other abdominal surgery unless the main target is more or less right next door.
Posted by: Joshua | February 19, 2007 12:04 AM
Wrong. We'd expect the frequency of appendicitis to increase, as people with smaller-than-the-critical-diameter appendices survived and passed on the gene combinations that would have normally been screened out.
Posted by: Caledonian | February 19, 2007 12:46 AM
A friend of my stepdaughter nearly died of appendicitis because when she went to Emergency with abdominal pain a doctor told her to jump and she did. That was the doctor's test to eliminate appendicitis because it would be too painful for anyone to follow the instruction. (Old doctor's tales, anyone?) Never pre-judge someone else's stoicism.
I've heard of two examples about 60 years apart where women were sterilized "while the doctor had them open" to operate for appendicitis, both times on the advice of a neighbour that they had too many children to take proper care of.
Posted by: Monado | February 19, 2007 12:54 AM
Clearly a case of overzealous malpractice suits. The surgeon is of course the most qualified individual to decide what's best.
Posted by: Caledonian | February 19, 2007 1:34 AM
C writes: "We'd expect the frequency of appendicitis to increase, as people with smaller-than-the-critical-diameter appendices survived and passed on the gene combinations that would have normally been screened out.."
Right, C, and that's why I'm intrigued by the *absence* of a decline in acute appendicitis cases in the more recent literature. Like I said, an interesting case...SH
Posted by: Scott Hatfield | February 19, 2007 2:05 AM
Well does it have a use in the young?
As "Look I know how to swear and use capital letters, so I'm a big boy/girl Ichthyic" asked for references and it is an interesting question I had a look, not a lot online but there is something (perhaps Icthyic hasn't heard of talk origins).
In a presentation from the malawi project
http://www.pathologyscotland.org/index.php?page=scotland_malawi_project
one slide does mention that it contains lymphoid tissue in the young http://www.pathologyscotland.org/download/scotland_malawi_project/git/257,2,Appendix
Sadly I can't find other details on the site about this.
Though it is a interesting site.
A site, that I am sure that you all know, has an article on this very subject http://www.talkorigins.org/faqs/vestiges/appendix.html
and in the section on possible function it is written "...Several reasonable arguments exist for suspecting that the appendix may have a function in immunity. Like the rest of the caecum in humans and other primates, the appendix is highly vascular, is lymphoid-rich, and produces immune system cells normally involved with the gut-associated lymphoid tissue....".
Perhaps the scientific/medical jury is still out in respect to its total uselessness in the young.
In adults it does appear to be an accident waiting to happen.
As vestigial can also be used to mean greatly reduced function, as well as no function, it isn't wrong to call it vestigial even if it does have some remaining utility.
Posted by: Chris' Wills | February 19, 2007 2:20 AM
and after all that, chris still doesn't grasp what a primary citation is.
nice bit of concern trolling though.
I'm sure JVC appreciated it.
moron.
Posted by: Ichthyic | February 19, 2007 2:32 AM
chris, here's a hint:
compare what you just did to what Scott Hatfield (current Molly award winner) did when he looked at the question of whether the appendix would eventually disappear entirely in humans.
note the differences in the types of citations used.
note HIS are primary citations, which can then be looked at directly for accuracy of method and conclusion.
get it now?
and people wonder why swear words are appropriate.
Posted by: Ichthyic | February 19, 2007 2:37 AM
Dear Ichthyic,
(Fisher 2000; Nagler-Anderson 2001; Neiburger et al. 1976; Somekh et al. 2000; Spencer et al. 1985).
Just have a look in the talk origin link I left, all the citations are there. No need for me to re-invent the wheel.
have fun using your dictionary of insults and swearwords, makes you sound so grown up.
Posted by: Chris' Wills | February 19, 2007 2:41 AM
LOL. and your concern trolling makes you sound like ever more of an idiot.
please, more!
why don't you actually READ some of those references linked from TO.
then come back and make an intelligent point.
Posted by: Ichthyic | February 19, 2007 2:49 AM
I myself haven't missed my brain since that stroke tried to kill me.
Useless, they are.
Posted by: Lettuce | February 19, 2007 3:35 AM
I am sorry, but the vermiform appendix is a horrible argument for supposed evidence for evolution.
There are tons of things that only make sense in the light of evolution, and the appendix is not one of them. You can remove areas of M.A.L.T. or lymph nodes without much of an effect on a humans overall health, but that does not indicate the lymphatic system is vestigial at all now does it? Heck, you can remove a whole lung and a person can still live rather well (I know that statement is relative).
The main argument is that the V.A. can get infected and bring about death, yet so can't a bad tooth infection, but again, it would be silly to argue teeth as being vestigial due to this.
This argument is out version of the God of the gaps. If one day we find a selective reason for the V.A. being there, then our faces will be rather red, and this need not be because there are many much more compelling anatomical reasons to know evolution to be true...
The vermiform appendix is not unlike the pyloric ceca in many predatory fish. We still are rather uncertain as to what pyloric ceca do in fish, yet we do not just assume they are vestigial elements, and due to this we are still attempting to study these features. Once we decide something like the vermiform appendix was vestigiall, little gets done to try and find out if it is there for a set reason...
This issue only helps creationists in the long run...
Posted by: Lago | February 19, 2007 3:52 AM
Dear Icthyic,
Try reading them yourself.
The paragraph quoted below is from one of them, it's just before the summary starts.
http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=1233252&pageindex=15#page
"The evidence presented herein points to the appendix vermiformis as being a structure which develops progressively in the higher primates to culminate in the fully developed organ seen in the gorilla and man, and confirms the contention (Le Gros Clark, 1971) that although the function of the appendix is still obscure, it should not be regarded, in the anthropoid apes and man, as a purely degenerative structure"
Posted by: Chris' Wills | February 19, 2007 4:21 AM
"yet so can't a bad tooth infection"
Way off topic here, but Lago, are you from Mass.?
Assuming that your use of can't isn't a typo, that makes me think you might be, since you didn't say "so CAN," though you clearly meant it.
There's a little isolated town in NY where I discovered that people have a habit of saying "so don't I" when they really mean "so do I." I was investigating this and found out that its supposedly common in Boston and is called a "Massachusetts Positive Negative."
Which is why I'm asking.
Posted by: craig | February 19, 2007 6:46 AM
Yep, I am from Mass, and I know I do that. When I travel, people look at me all confused. I never thought I sounded like I was from MA., but the first time I traveled, everyone made fun of me for so obviously being a Bostonian...
Posted by: Lago | February 19, 2007 7:02 AM
Oops, and I forgot..., when it comes to saying, "So don't I", I do as well, or better said..."So don't I".
I try to write well, though, more often than not, fail to do so, but in reality, my actual speach has so many odd-ball influences, that I am barely intelligible. Be glad you only had to read what I said, and didn't have to listen to it..
Posted by: Lago | February 19, 2007 7:12 AM
Ichthyic, I don't understand why you have to be so abusive and rude.
It would be wonderful if I could remember the references for everything I've ever read, but sorry, I'm only human. I was going from what I'd seen about 10 years ago, after asking my father the same "does the appendix have a function?" question.
I feel patronising having to say this, but believe it's necessary...
Comments sections aren't research papers, they exist to stimulate discussion and inform both scientists and non-scientists alike. Telling commenters "don't even bother to [contribute]" unless they can provide a citation isn't constructive and would make for very short discussions. SEF doesn't provide citations either, but what he said still seems plausible to me.
As an aside, I was writing at nearly midnight CET, so even if I did want to provide the primary literature sources, I wouldn't call my over-worked dad so close to his bedtime ;)
My only point was that an appendectomy (removalable/dispensible after birth) doesn't prove that the appendix is never functional.
windy, answers to New Scientist "The Last Word" questions can be provided by anyone, so we have to trust that the respondant has some authority/experience on the subject.
Chris' Wills, I disagree that the appendix isn't a vestigial structure, as its primary function should be in digestion (I think that our definitions of 'vestigial' differ though). Oh, and thanks for the "concern trolling" ;)
Posted by: JVC | February 19, 2007 7:43 AM
I spend spring break of my first year in college in a hospital up in Canada because my appendix ruptured. I initially thought it was the killer spicey chili my friend's dad had cooked for us all the night before, but obviously I was wrong. I had great treatment, and they never once asked me about how I was going to pay. They did eventually send my parents a bill, but there was never a question of payment being an issue for treatment.
My mother had an incidental appendectomy in '65, and she was not asked in advance. While she thinks she probably would have agreed if asked, it's always upset her that the doctor choose to simply remove it while they were there without asking anyone.
Posted by: Phi (Nic McPhee) | February 19, 2007 9:15 AM
JVC,
If the primary function should be in digestion, then, I agree with you it is vestigial in the sense of being redundant.
It is the research showing that it still appears to have a function as part of the lymph system (for good or ill) and from the quote from http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=1233252&pageindex=15#page
that it appears to have developed progressively in the anthropod apes and man that makes me consider the possibility that it has been retained/co-opted for another function.
Posted by: Chris' Wills | February 19, 2007 9:34 AM
"Oops, and I forgot..., when it comes to saying, "So don't I", I do as well, or better said..."So don't I".
I try to write well, though, more often than not, fail to do so, but in reality, my actual speach has so many odd-ball influences, that I am barely intelligible. Be glad you only had to read what I said, and didn't have to listen to it.."
I got the name wrong, its a Massachussetts Negative Positive, and I've just added this siting of another version in the wild in the appropriate thread over at the Eggcorns Database:
http://eggcorns.lascribe.net/forum/viewtopic.php?pid=2763#p2763
...though this is not an eggcorn.
Posted by: craig | February 19, 2007 9:55 AM
Oh ye of little faith, PZ, don't you realize that the appendix is the seat of the soul? Explains a lot, doesn't it?
Posted by: theophylact | February 19, 2007 10:16 AM
JVC wrote: windy, answers to New Scientist "The Last Word" questions can be provided by anyone, so we have to trust that the respondant has some authority/experience on the subject.
No we don't have to trust them and in this case we shouldn't trust them at all, since that respondent was obviously wrong: there can't be any "foreign antigens" or bacteria in the appendix during fetal development.
Lago wrote:
There are tons of things that only make sense in the light of evolution, and the appendix is not one of them.
Yes, it is. Perhaps it isn't a completely functionless vestigial structure, but it's clearly an organ of minor importance left over from ancestors where it played a much larger role.
As for the appendix being rich in lymphatic tissue and endocrine cells, I'd be more surprised if it was just composed of dead, inert tissue instead of gut cells doing what gut cells usually do.
Posted by: windy | February 19, 2007 10:33 AM
So you some times have to get your soul removed to save your life?
Posted by: Kristjan Wager | February 19, 2007 10:34 AM
Just because the appendix is connected to the lymphatic system doesn't mean that it has a function.
By all indications, it is indeed a dispensable organ. I suspect dire motives among those here trying to suggest otherwise.
Posted by: Caledonian | February 19, 2007 10:34 AM
Are different groups more susceptible to appendicitis?
I (and my parents and siblings and grandparents and cousins) have never had any trouble with the appendix.
I also have my tonsils; my mother said when she was a child they were taken out routinely. She said the doctor was at the house one day when Mother was 12, and when it was mentioned that she still had tonsils, the doctor insisted that surgery be scheduled. They were removed within a week.
Posted by: khan | February 19, 2007 2:08 PM
Lago wrote:
There are tons of things that only make sense in the light of evolution, and the appendix is not one of them.
Windy responds: Yes, it is. Perhaps it isn't a completely functionless vestigial structure, but it's clearly an organ of minor importance left over from ancestors where it played a much larger role.
As for the appendix being rich in lymphatic tissue and endocrine cells, I'd be more surprised if it was just composed of dead, inert tissue instead of gut cells doing what gut cells usually do.
See, you are making claim that "it is", as is vestigial, yet this is pure speculation. A vermiform appendix is very common in mammals from rodents to primates. It was claimed to have been only used as a digestive organ in "our ancestors" and hence, because of this, shows it is vestigial now. This is a circular argument as you have already assigned to it the "proper function" as you see it, and then state it has lost this function, hence "vestigial". Perhaps it has another function common to the many mammalian groups that have it, and any digestive abilities it ever had, were the odd-ball selective events.
Again, as I stated above, the pyloric ceca of fish look quite similar to the vermiform appendix, and some fish are just loaded with them. If we assumed an ancestral function of the pyloric ceca as being digestive, we might consider them vestigial as well, but since this did not occur, we see them as simply confusing right now. At least we are still trying to figure out the purpose of these digestive diverticulum instead of assuming we already know. Again, this is our version of "The God of the gaps" where, because we have not figured out exactly what the selective pressure is for keeping the V.A., we assume it to be vestigial. Such thinking only eventually helps creationists.
And again people, just because you can remove something without killing the organism does not make the structure vestigial. You can cut off fingers, remove lungs, remove tonsils, pull teeth, etc... all day long and a human can still go about a mostly normal life. We do not just assume a vestigial nature to all of those elements due to this...
Posted by: Lago | February 19, 2007 2:56 PM
I know the "small appendices get infected more easily" theory has been floated, but has anyone actually confirmed it with a study?
Posted by: Anton Mates | February 19, 2007 2:58 PM
"Posted by: Caledonian
Just because the appendix is connected to the lymphatic system doesn't mean that it has a function."
And just because you've assumed it has no function does it make it so (re-read my above response). We've assumed numerous tissues were vestigial before only to have found out we were incorrect. How abouts we try not to do that again, eh?
"Posted by: Caledonian
By all indications, it is indeed a dispensable organ. "
So is a molar, but this does not make molars vestigial...
"Posted by: Caledonian
I suspect dire motives among those here trying to suggest otherwise."
Alien invasion?
Posted by: Lago | February 19, 2007 3:20 PM
I don't see anything circular about it, myself. The claim that the ancestral primate appendix/caecum was used for digestion is not based on the uselessness of our own, but on phylogenetic analysis of modern primates.
It is, certainly, possible that the caecum was even larger and had some other primary function in mammals of an even earlier era. That would simply make it doubly vestigial.
Sure, but in the case of the appendix it appears that you can remove it with no medical effects whatsoever, except from the operation. It's not just that the human has a "mostly normal life;" it's that the human has a completely normal life and risk of future medical conditions so far as research can determine. That's not true with fingers, lungs, teeth--dunno about tonsils.
You can't really get more vestigial than that; we classify blind cave fish eyes and kiwi wings as vestigial based on considerably less conclusive evidence. The structures are smaller and simpler than they were in those organisms' ancestors, and less important to their existence; that's all you need to make the call.
Posted by: Anton Mates | February 19, 2007 3:28 PM