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.
This demonstrates the careless arrogance of surgeons better than it does the redundancy of the appendix.
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?
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. . . .
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.
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?
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.
Skeptyk:
I asked the same question over at Surgeonsblog, so maybe the author of the original post will reply.
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.
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!
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?
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
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.
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.
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.
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.
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!
(-;
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!
You’re not alone. I’m 50 and still have both too. I think only about 7-9% of the population ends up having appendectomies.
According to Oprah and her weird friends, apparently if we wish hard enough they’ll just go away. ;-)
Thanks for the elaboration, Orac!
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.
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).
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).
(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).
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.
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 ;)
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.
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.
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.
I bet if we were all in the same room we’d be comparing appendix scars by now.
Thanks, Orac and all, for the info.
“Incidental Appendectomy” Rhythmic, flowing, nice name for a band.
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…
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.
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.)
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.
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?
Skeptyk, so you believe people can modify their behavior and prevent appendicitis?
You should appear on TV infommercials with Kevin Trudeau!
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.
Mine didn’t try to kill me until I was 11. I haven’t missed the little sucker in the slightest.
“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.)
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.
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…
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.
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.
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.
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
“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.
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.
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.
Clearly a case of overzealous malpractice suits. The surgeon is of course the most qualified individual to decide what’s best.
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
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.
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.
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.
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.
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.
I myself haven’t missed my brain since that stroke tried to kill me.
Useless, they are.
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…
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”
“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.
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…
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..
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” ;)
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.
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.
“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.
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?
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.
So you some times have to get your soul removed to save your life?
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.
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.
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…
I know the “small appendices get infected more easily” theory has been floated, but has anyone actually confirmed it with a study?
“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?
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.
Anton,
…tonsils are there for a reason right? You can have them removed and live a pretty damn “normal life, correct? They can get infected and bring about problems to the organism as well, correct? Tonsils of some-sort are also very common in animals, correct?
…Vermiform appendix fits this same description except we assume it purpose was originallly for digestion, and due to this we make claim it is vestigial. The fact is, as i stated above, many animals have a vermiform appendix, from rodents to primates. It is actually a relatively common feature. By making the mistake of assuming it had only one usuage before, you set yourself up for pie in the face if and when an actual selective pressure is found for having the V.A.
Now, tell me, how is this structure that different from what we see in the pyloric ceca, where we do not just assume a vestigial nature? Only because we have not assumed a vestigial nature do we still attempt to answer the question of what use are pyloric ceca, but if we assumed it was just a left over element of a digestive diverticulum, we would be stuck, not looking for answers..
At the risk of invoking cognitive dissonance, I agree with Caledonian, and I think some of the commenters are missing the point.
What makes an organ vestigial is not the absence of any present function. What makes it vestigial is that it provides evidence for common descent, in that the organ is homologous to functional organs in other taxa, but lacks those organ’s present function. So the question of whether or not the VA has any present role in humans in terms of the lymphatic system is irrelevant to the question of whether it is vestigial. In fact, if it were to be discovered that VA cells produce digestive enzymes that would still be irrelevant, since it manifestly is not providing the digestive function found in the homologous marsupial organ.
I think repeated failure to acknowledge this point would cause me, like Caledonian, to wonder about another’s motivation.
“I think repeated failure to acknowledge this point would cause me, like Caledonian, to wonder about another’s motivation.
Posted by: Scott Hatfield”
First, I would like to say I that can give far better evidence for evolution from anatomy than the vermiform appendix. Any motivation on my part is based on seeking truth, and not avoiding critical thinking when it comes to an issue just because there is conflict.
Next Scott says:
“….What makes an organ vestigial is not the absence of any present function. What makes it vestigial is that it provides evidence for common descent, in that the organ is homologous to functional organs in other taxa, but lacks those organ’s present function. So the question of whether or not the VA has any present role in humans in terms of the lymphatic system is irrelevant to the question of whether it is vestigial. In fact, if it were to be discovered that VA cells produce digestive enzymes that would still be irrelevant, since it manifestly is not providing the digestive function found in the homologous marsupial organ.”
The above assumes too much. If we accept your premise of original usage, and assume no other usage has developed, then fine, but those are assumptions. As I stated above several times, the V.A. is a rather common element in many mammalian groups, and it gets a little bit pushy to suggest it is vestigial in all of these separate groups, yet still so common with little selective pressure against…
We need not assume that a digestive trait was the lone trait, and can assume there may have been another. What if the V.A. is a store area for bacteria used in the breakdown of a common food in our ancestors, and was used to replace these bacteria more quickly after a sickness has occurred that greatly diminished their numbers? What if this was the original usage of this diverticulum, and any digestive ability was a secondary selective event? This would make the removal of the digestive aspect mute when it comes to the actual selective pressure of the element in question, and would make the remaining aspect of the appendix not vestigial.
Of course I am just making a abstract point that borders on a hypothesis here, and I am not actually claiming this to be so, but I am saying no one is looking because they already have there minds made up. Remember what happened when we had out minds made up about what causes ulcers? How did that work out again?
Once more, again, if we had assumed the pyloric ceca in fish were vestigial, we would have stopped looking for their usage. It is only because we did not stamp these similar digestive diverticula as “vestigial” that we press on looking for answers.
See, removing tonsils *does* compromise the immune system. It just doesn’t do in a lethal fashion. People without them are *slightly* more susceptable to diseases than those with them. The problem of course is that they become inflamed precisely because being less susceptable to a wide range of diseases means an increased risk that any one of them will, I guess you could say, overload a organ that *only* provides immunilogical responses. And as for the idea that fetuses don’t have foreign bacteria in them before birth… That’s not necessarilly a reasonable assumption. They breath fluid while in there as their lungs develop. There is no logical reason why they wouldn’t also develop swallowing reactions as well, and the fluid they swallowed “could” occationally contain foreign bodies, which an organ specific to dealing with dealing with foreign bodies in the incomplete and still forming gut might be useful, until other immune systems can take over and are more mature.
I have to agree with several people here on two points a) its not always possible to go back to original sources (the one I read on it was from 5-6 years ago and I am not sure I even have the magazine issue any more) and b) its not scientific to just go, “Bah! That doesn’t do anything!”, when you might be dead wrong, even if there are reasons to think so. In other mammals that don’t have an appendix, there is no more reason to predict that they didn’t “need” one, so ours it automatically useless, than to predict that the reason they don’t need one is because what ever function it does have “may” have been taken over by other organs/tissues. I say the jury is out, and as others have stated, the ability to live without something doesn’t automatically means its not having and effect at some point in development or when missing.
Arrggg… I am out of the office for 2 days and I missed a great post like this! But 78 comments is way too many to read through right now, so I will just wait for another time to comment. PZ, can you post about another vestigial organ?
z.
Lago, you raise some interesting conceptual problems that are, frankly, outside of my bailiwick. However, I must demur from the following statement: “if we had assumed the pyloric ceca in fish were vestigial, we would have stopped looking for their usage. It is only because we did not stamp these similar digestive diverticula as “vestigial” that we press on looking for answers.”
I have to quibble here, because the invocation of an organ’s “vestigial” status would only constitute a ‘science-stopper’ IF we regarded “vestigial” as synonymous with “non-functional.” I have previously pointed out this is incorrect, but don’t take MY word for it. Here’s a highly relevant passage, minus citations, from the erudite Douglas Theobald:
“…it is unnecessary for vestiges to lack a function. Many true vestiges are functional. In popular usage “vestigial” is often believed to be synonymous with “nonfunctional”, and this confusion unfortunately has been propagated via poorly-worded definitions found in many non-technical dictionaries and encyclopedias. Even some professional research biologists have fallen prey to this oversimplification of the vestigial concept. The statement that vestigial structures are functionless is a convenient, yet strictly incorrect, approximation. It is analogous to the common, yet strictly incorrect, scientific claim that the earth is a sphere.”
The full meat, along with the citations, can be found here:
http://www.talkorigins.org/faqs/comdesc/section2.html#morphological_vestiges
Enjoy!
Dear windy
Note that you placed emphasis on “have”, not me. It’s a (perhaps British?) figure of speech, as in one assumes that they’re telling the truth, although obviously that might not necessarily be the case. I was responding to your general query about the credentials of “The Last Word” respondants.
Sorry, after writing such a long reply, I simply forgot to respond to your specific contention against foreign antigen presence during fetal development. Kathleen James’ reply was indeed a little unclear. It was a round-about way of answering so, from my experience, I’d guess that she’s a medic ;) Nonetheless, she is not wrong.
Here are a few results from PubMed. Unfortunately, the papers are behind a subscription wall, but if you’re interested, e-mail me and I’ll forward you the PDFs :)
Scott,
I have studied the term “vestigial” for years. I do not care for call to authorities from sites like Talk Origin, mostly because they do not take enough time to update material to current papers (Are they still claiming Whales are from Mesonychids?), but also because opinions and definitions vary quite a bit for different people.
For example, one cannot claim proof for evolution by stating evolution is simply defined as frequency change of an allele in a given population, and then showing them such. This is because most creationists are not debating that issue (though amazingly enough, some even debate that). What most creationists define as evolution is “kind to Kind” where they see separate kinds as reptiles, from birds from mammals etc…
When we say there is evidence for evolution, you can discuss frequency changes ’til the cows come home, and they will just look at you like a rabbit caught in headlights. What one needs to do is ask them to define the osteology of a reptile, and then that of a mammal, then quantify the differences. Then you show the the fossils of therapsids and ask them to explain how these animals do not qualify as “intermediate”?
This can be applied to the term vestigial as well. There are numerous tissues in the body that were early on claimed to be vestigial. Most of these turned out to be far from vestigial, and down-right important. Creationists are taught this all the time, and when you show someone something and claim it to be vestigial, you better make it rather obvious.
Making claim they are vestigial because they do not do as much, or as much the same as it did in an ancestor is like trying to claim to a creationist a seals flipper is vestigial because it no longer makes a good foot. If that sounds funny, then you know how it sounds to a creationist. Using a definition that they are not does not help your case, but merely drags the debate into semantics.
Here is a piece of a post I have used on other sites when trying to explain vestigial organs to creationists, with what to use, and what not to use when debating them, and why:
“When it comes to vestigial organs we really must define the term a bit first. Many people define vestigial in differing ways when it comes to such items as organs. A few of the basic versions are;
Anything that is there but does nothing.
Anything that does little but seems to do much more in related species.
Something that was used in a past niche that seems to do little to nothing now.
The problems with all of these definitions are that they tend to be in the eye of the beholder. Some in the 1800s thought the thyroid was a vestigial organ and that?s the same with the vermiform appendix today. When the vermiform appendix get inflamed today and gets removed to help save someone?s life we think that it was almost parasitic in nature. Doing nothing and having the ability to kill the organism it is part of make the case seem a bit obvious. What we do not think of is the fact that a tooth infection can and does kill many without helping redefine teeth as vestigial. When it comes to the fact that we use teeth and need them to survive, this to most would indicate teeth are on a different level than the vermiform appendix. The thing is we can loose teeth as well and still survive. Not only that, we can also loose a kidney, a lung and many other things and still keep going. We will, however, not do as well. This is the same with the vermiform appendix which does contain M.A.L.T.. M.A.L.T. stands for mucosal associated lymphatic tissue. You may find this structure is quite common in many mammals including the primates. Just because our best knowledge of its overall purpose seems to be sending the kids of medical surgeons to college does not mean it does not give support to the overall health of the organism.
One way to look for structures that make little sense is to look at development and the fossil record at the same time. By evolutionary theory we predict that there are basal forms of differing organisms that spread out in differing directions from a particular node (point of origin on a cladogram). Take again the mammals. Basal therian mammals all had incisors as well as the early artiodactyls that evolved from them. Modern artiodactyls like the bovines do indeed still have incisors on their lower jaws but the upper incisors have been replaced by a keratinous (horn like) beak under the upper lip. If God made these animals as is there would be no reason to find upper incisors in the fetal versions of these animals?but we do. Same is with the famous equine versions of toes. A foot going from the ankle down consists of the tarsals, metatarsals, phalanges and finally distal phalanges known in horses as unguals (hence the term ungulates for both the artiodactyls and perissodactyls). We all know that horses have one toe at the end of their feet today and that the horses in the fossil record had more the further you go back in geological time. Again in development we see more than one metatarsal form. These bones do not fully develop and end up fusing to the sides of the main metatarsal (the 2nt ) and are seen only as small splints. Familiar developmental patterns can be seen in the birds in which a fifth metatarsal is seen developing in embryo that is similar to what is seen in adult non-avian dinosaurs considered closely related to basal birds. The important thing is no bird today after hatching has a 5th metatarsal. Same can be said of the unguals (claws) in birds that develop in most embryos of birds but are rare in hatchlings onwards. Some birds do retain their claws to adulthood but they are usually ground oriented birds that do not fly well and one that climbs as a chick while in the trees. Out of over 9000 species of birds though pretty much all develop unguals in their embryonic stage but under 10 keep them past hatching and to adulthood.
People could try and argue usage and deny an altered developmental path but it gets harder to do so with the more examples we find of this type. Lets take the whales. There are two main lines of whales usually recognized. They are the toothed whales and the baleen whales. We know that one has teeth as the name implies and the other a straining form of keratin knows as baleen. Never do the baleen whales use teeth to acquire their food. But again, what do we see during development? The formation of tooth buds in the same place where the toothed whales have teeth but these are reabsorbed, never used, and then later replaced by baleen. Whales also hear in a manner that is far different from the way land mammals do. With whales sound travels through parts of the skull with little odd ball traits involving things like non-symmetrical teeth on either side of the jaw to help each ear receive the vibrations at a slightly different time. This helps whales define distance and 3 dimensional space by way of sound. What whales do not do is use external ears to gather sound. Many land mammals use external ears and muscles to change the orientation of their ears to pick up sounds in different directions. Again, what do we see as the whale develops? We see the early development of external ears complete with auricular musculature. Such organs would be of little use to an animal that lives under water and even less to a fetus?but they have them, and only when developing before birth. This can be done with so many features of animals like whales because of the huge amount of change they went through. Whales are a form of artiodactyls along with cows, deer, pigs hippos and so on. Most of these animals have their nostrils on the front of their snouts. It would be expected that whales developed from animals that did so as well. Again, during development, the nostrils actually migrate backwards from a forward position on the face to get to their position at birth.
Developmental oddities are common but there are many oddities as you can see that are part of the common developmental pathways of the vertebrates in general. It?s a common myth that vertebrates all start out as females but the facts are slightly different. We and other vertebrates actually start out as hermaphrodites with both male and female traits. For example, both start out with an ovotestis which is combo of both the female and male gonad. Also, the dual Paramesonephric ducts that will grow fuse and become the uterus, are also seen during development in men. These ducts can only be seen as tiny varied tube like pieces of tissue fused to the testes in case of the appendix testes and fused near the urethra and prostate in the case of the prostatic utricle. Why males start off with the same elongated duct that in females becomes the uterus and in the end becomes tiny pieces of tissue that resemble neither the uterus or the original duct is to say at least odd in the view of factual creationism.
Let us also not forget simple things like the nipple. Creationists sometimes give varying reasons on why men have nipples and most have to do with God making them from the same basic idea. What confuses the issue is not only do all male mammals have nipples as well (usually hidden under their fur so visual reasons are out as a purpose there) but we ourselves have, again, as we develop more nipples than we do once we are born. Placental mammals (including humans) develop what are called mammalian ridges. These ridges run down the sides of our bodies from our arm pits to our upper legs in both males and females showing a series of developing nipple structures. Humans as we all know, usually end up with only one pair in the pectoral region. Why does God go out of his way to do such things if he created us as is from the start?
The vertebrate tongue is much the same. Humans and all vertebrates are segmented creatures though most segmentation is lost way before birth in mammals. Segments called somites in the cervical region (neck) actually migrate to the region of the jaw to become the muscle of the tongue. Now the spinal nerves are made up from a dorsal sensory root which contains a sensory ganglion and a ventral motor root that inserts and controls the muscles and other tissues that can be stimulated in varying ways. When mammals develop both the dorsal and ventral nerves are present. Four of the most anterior ganglia that are associated with the motor neurons that innervate the migrated muscles of the tongue will later degenerate while the vertebrae in that region will fuse onto the back of the skull forming the occipital region.
These ganglia (called the ganglia of Froriep?s) are developed from neural crest tissue in the same manner as others sensory ganglia but just as stated degenerate before birth. It could appear to an unbiased person that such a development and later degeneration of so many sets of organs that in other animals become functional might make one doubt Creationism in it?s ?we were created fully formed? version.”
I really should go back, and rewrite the above. More needs to be added, and poor wordings need to be cleared up. For example, I should add in with the whales all the known evidence from hindlimb formation. I should also clear up things like when I discussed somites and said they migrate. Of course, what I really mean is that the myotomes part of the somites produce cells that migrate..
I hope people have a better understanding of what I am gettin’ at now.
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.
Lago wrote: See, you are making claim that “it is”, as is vestigial, yet this is pure speculation.
That wasn’t the claim that I was responding to. You said “only makes sense in the light of evolution”, not the same thing as “vestigial”. An organ we can very well do without in adult life, and which occasionally kills the person, only makes sense in the light of evolution to me (but not pan-adaptationism). The only option would be a malevolent designer but the appendix doesn’t seem malevolent enough :)
I think it is a matter of point of view, wings on ostriches are vestigial for flight but useful in courtship display.
“I have nipples, Greg. Could you milk me?” Sorry, couldn’t help myself.
Interesting #82 post Lago. I agree with your main point (also stated in #57), that the appendix is not a good case for defending evolution, in part because of the confusion between any kind of function and being ‘vestigial’ structures.
On a related note, I’ve never been comfortable with arguing for/against whether functional structures are dispensable or not. For instance, with the above example of the appendix, we could say “if we find healthy humans that have never had an appendix, then the organ must be useless”. However, there are numerous examples of (let’s call them) “knock-outs” (e.g. genes) in model organisms, such as mouse and yeast, where the individual appears normal. My problem with this argument is that they’re only normal under the observed (environmental) conditions, which may not necessarily be ‘natural’ (i.e. lab. conditions).
I haven’t thought about this intensively, so I welcome others’ comments on the functionality/dispensability issue.
Lago: You make an interesting argument, but tactically I think you’re all wet. I can rebut this claim with a few well-placed sentences: “You’re using the term ‘vestigial’ in a way that evolutionary biologists, including Darwin, never intended. Structures such as the appendix may very well have some present function, but not the same essential function shown in marsupials.”
And then go on. Your approach, while scholarly, is an enormous waste of time with most of these folk. They aren’t interested in having a nuanced discussion. They are interested in a talking point; I’m interested in depriving them of that talking point, and demonstrating the half-baked nature of their claim. The fact that these structures are a puzzle for special creation but not for evolution is key, not some argument over definitions. You can’t make this go away by arguing that is has some function now; you still have to explain why it persists,with a different function, in some other lineage.
I know the “small appendices get infected more easily” theory has been floated, but has anyone actually confirmed it with a study?
Since post-mortems probably do not routinely examine and measure the healthy appendices of patients dead for some other reason, I suspect the requisite data are unavailable. However, I refer you to the example of diverticulosis (which, as I mention above, is a condition of personal interest to me) as being possibly relevant. The diverticula, as I understand it, roughly resemble small appendices, and have a similar but much higher risk of impaction and inflammation (and which would presumably be similarly lethal in the pre-antibiotic era).
JVC wrote: Sorry, after writing such a long reply, I simply forgot to respond to your specific contention against foreign antigen presence during fetal development. Kathleen James’ reply was indeed a little unclear. It was a round-about way of answering so, from my experience, I’d guess that she’s a medic ;) Nonetheless, she is not wrong.
OK, those references clarified things a bit, I didn’t consider maternal antigens and so conflated foreign antigens with bacteria. But so did Kathleen James, it seems. I still feel that bringing bacteria into it at all is wrong – AFAIK live bacteria in the amniotic fluid is a serious complication and not something that the appendix would have evolved to deal with.
Scott states: “”You’re using the term ‘vestigial’ in a way that evolutionary biologists, including Darwin, never intended. Structures such as the appendix may very well have some present function, but not the same essential function shown in marsupials.”
First of all, this implies that whatever was used in marsupials is basal to what is used in placentals, and this assumes a point not shown.
Next, terms are defined by the context of the debate. In this debate, the idea of vestigial only matters on those points used by what you are trying to show true. Face the simple fact that we are trying to use the term “vestigial” as meaning those traits that do not make sense unless they are of no use for what they were once intended for. A reduced usuage means nothing to this debate because creationists are not swayed by this tact, as all they see by the same evidence is different levels of usuage, like big tires on a truck as opposed to small tires on your sedan.
If you point towards a land mammalian predator and show that it has feet, and then point to a marine mammal and show that it has flippers, one cannot simply argue a vestigial nature to these elements to a creationist as they do not agree with you on the evidence. They still see an animal “Made” for its environment “as is”. This, despite the fact that the feet of such in the marine mammal still qualifies under your definition as being a vestigial element.
However, showing a fossil of a living animal that does not possess feet with them as a fossil, as we see in the fossil record of whales and dugongs, does help, but they still can claim they are just separate, yet similar looking animals from the past before “The fall”.
What breaks down their argument is the fact that these animals will usually show elements of these same traits (in this case, “feet”) during development. Since a creationist see what they consider an obvious trait, like a foot or teeth, in an animal that does not, by their definition, use them, then the definition used in “This” debate is fulfilled, and we win. Will they still try and argue around this as well? Of course they will, but the key is, we have given them evidence based on a “Mutual” definition of the term “vestigial” and did not simply use semantics where both sides argued from a different point-of-view on the definition.
PS, on a side note, “vestigial eyes” in blind cave animals fit the definition of vestigial for both the average biologist, as well the average creationist. One must remember that the loss of something alone does not indicate evolution to a creationist, as they believe the world iss in a state of decay they call, “The Fall”. Using feet of whales does work, however, because they believe those traits go to terrestrial animals, which they claim whales never were. Using teeth also works because baleen whales have an element that is too complex in the place of their teeth that does not come under the definition they give when dealing with “The Fall”. In other words, baleen is an example of a trait they believe requires a special creator, and not one that simply results as the act of decay brought about by The Fall, and they cannot have their cake and eat it too when it comes to both baleen and teeth…
I hope you are now starting to understand the true debate that is taking place when you are dealing with creationists. Misunderstaning them does not help you debate them…
Not necessarily. That marsupials and placentals share a common ancestor was well-established by comparative anatomy prior to the modern synthesis, and this has been confirmed by molecular data. Whether or not the present function in marsupials is basal to that lineage or the common ancestor that they share with placentals does not change the fact that any function in placentals is arguably a) distinct and b) non-essential. This largely non-functional appendage in humans is a ‘vestige’ of our common ancestry with other lineages, some of which retain a distinct essential function.
At any rate, Lago, you raise some interesting points and if you’re just making the modest claim that we should not oversell vestigial organs or characters in dealing with creationists, I won’t quibble further. On the other hand, if you think we should abandon such arguments entirely, I have to disagree. My students are very impressed when they see the pelvic bones in whales and they often have painful experiences with their own vestigial tails.
As for the Fall, my little quip in response to such arguments would be to ask the creationist if they think Australia and New Zealand are less touched by original sin than the rest of the world; if so, why are there some pretty nasty creatures there, as ‘red in tooth and claw’ as the rest of Creation?
Jocularly…SH
“At any rate, Lago, you raise some interesting points and if you’re just making the modest claim that we should not oversell vestigial organs or characters in dealing with creationists, I won’t quibble further. On the other hand, if you think we should abandon such arguments entirely, I have to disagree. My students are very impressed when they see the pelvic bones in whales and they often have painful experiences with their own vestigial tails.”
I am far from against using vestigial elements. I just know how they are defined by creationists, and it is that definition we must also use if we are debating creationists on the issue of vestigial. Also, If you re-read what was said, I gave the pelvic bones of whales as an acceptable version of vestigial in this debate for reasons noted above. I simply do not believe that the vermiform appendix is acceptable for this type of debate because it is a possible bomb that can blow up in our faces..
Lago: OK, you’ve convinced me that some diligence is required here. I’ll continue to refer to the appendix when dealing with my high school students (among other examples) but in public dealings with creationists I’ll take the better part of valor as you suggest, rather than possibly light something I’d have a hard time defusing.
This was an interesting exchange. Good talking to ya.
Sure, but none of the above is particularly relevant to whether they’re vestigial or not. The question is whether we have reason to think our ancestors had bigger or more complex ones, which served a function ours do not. If that’s true for tonsils, then hey, chalk tonsils up as vestigial too.
Now if the question is how best to confound creationists, then certainly you can’t start by talking about what our ancestors had, since they don’t believe our ancestors were nonhuman in the first place. But the appendix still beats out the tonsils in this regard so far as I know, because Schwab mentions actual studies showing that its removal has no statistically noticeable (negative) effect, and that’s not the case AFAIK for tonsils. Correct me if it is.
And note that this is a much better case for vestigiality than many others. In later posts you mention, for instance, fetal teeth or tooth buds in mammals that are born toothless, and pelvic bones in whales. Well, if you remove the teeth from a baleen whale or ruminant fetus, will it live a completely normal life after birth, with a statistically normal medical history? Has anyone actually done a study on this? (I’m sure it’s possible that someone has with a domestic ruminant; I’m pretty sure they haven’t with baleen whales.) If not, how can we be sure that they’re of no use whatsoever? Cetacean pelvic bones are even worse, because we know they have a function–muscle attachment.
Now I’m not saying there aren’t good reasons to consider them vestigial–there are. But if you’re just talking about arguing with creationists, those reasons don’t count for much, because they’re comparatively dependent on the fossil record. With the appendix, on the other hand, you can simply point to medical data that says it isn’t doing anything except hurting us.
No, not at all. We don’t assume its original purpose was for digestion, we infer that its original purpose was for digestion from phylogenetic analyses of the primate tree. This is no different than, for instance, inferring that our ancestors used their feet for grasping. You can certainly question whether the analysis is methodologically correct or based on sufficient data, but it’s hardly an assumption.
As I understand it, those appendices are almost certainly not homologous with our own, so that isn’t really relevant. Moreover, virtually all those animals are in primarily herbivorous taxa (mole-rats, rabbits, wombats), which lends further support to the idea that appendices are generally used for digestion or vestiges of same. In rabbits, the appendix actively secretes into the GI tract (at a much higher rate than in humans) during digestion.
Well, sure. That’s the risk with any scientific claim. If it wasn’t falsifiable, it wouldn’t be science.
Well, apparently it’s different in two ways. First, we have positive evidence of the pyloric ceca’s function, inasmuch as they dramatically increase gut surface area and synthesize large quantities of certain chemicals during digestion. Not so for the appendix. Second, we have positive evidence of the appendix’s lack of function, inasmuch as we’ve removed it from lots and lots of people without long-term medical effects. Not so for the ceca. Seems to me that adds up to a strong argument for appendix vestigiality and pyloric ceca nonvestigiality.
What makes you think that? We’ve considered the appendix to be vestigial for centuries, and that hasn’t stopped research on its function. The whole “maybe the appendix has an immune role” argument wouldn’t even have come up if scientists were “not looking for answers.”
Anton
The debate, IS one of creationism. It is in the second line for Pete’s-sake of the original post above. If you did not realize this, I suggest you take some time and grasp this before debating further…
Next, the immune role is only inferred by people who have not simply accepted a vestigial role of the vermiform appendix. That is consistent with every aspect of what I said…
By the way, we only have some speculations as to what Pyloric ceca do, and this research was only done because we did not assume a vestigial nature. Increased surface area has also been shot down as a reason most of the time..
Finally, the definition of vestigial as being the same but less does not work. Again, flippers on a seal are not vestigial, they are flipper even if, at one time, they had been feet…
Also, on teeth of baleen whales. We know these animals do not use them ever, yet we still know them to be teeth. Your weird ass requirement for surgery to prove a vestigial nature makes little to no sense at all. Because even if removal did bring about problems during development, which I bet it certainly would, it still doesn’t explain why this step would be added into a creature that was “designed” in “special creation” to be without teeth.
Same with the hip. It is not simply that there is a hip bone present with muscle attachments, it is the fact that buds start to develop there in the same manner as we see in terrestrial animals, and then, at the same time, we see the occasional hind-limb sprout from the region with a fully developed knee, which can either be reabsorbed, or kept in some cases. Why a thigh bone and knee would develop in an animal at a point that corresponds to what we see in terrestrial animals as being the pelvic region is a tad confusing to say the least in the view of special creation.
In reality, you simply are confused as to the actual issue. For example, we still develop a yolk sac during development, and this can be seen as vestigial by a given definition (by its great reduction and almost useless amount of yolk), but we cannot simply remove this during development as it is still part of the cascading events that brings about a newborn placental mammal. We cannot use a yolk sac with creationists to give evidence for something that is vestigial, because they see it as being there for a reason. You see, the yolk sac does not qualify by your method of surgical removal either, as in removal would be very problematic, and it does qualify by a comparative anatomists stand point. The thing is, we cannot use it well with a creationist because the yolk sac is tied to so many aspects of early development so does not qualify by an agreed upon mutual definition. I mean, to me, cardinal veins, and pronephros kidneys are great examples of vestigial elements, neither which could possible be removed without an extreme effect on development, but they are only good for evidence of shared developmental pathways* and are not useful to show a vestigial nature of a trait to a creationist…
(*as in the Haeckel debate, by showing the true evidence from development by modification of a general vertebrate “plan”, and not Ontogeny repeats Phylogeny)
Vestigial, for this debate, must be an agreed upon definition in which the definition of evidence is the same for both, or we babble off into semantics. Most creationist understand what a tooth is for, and do not dispute their usage. This is why their development in animals that not only do not use them, but have another extremely complex structure in their place hurts the creationist so bad. They are left with seeing teeth as vestigial, or claiming the teeth as part of the decay from the fall, while allowing for a newly developed complex structure to come about in its place. They are basically cornered cornered.
Uh, the “debate” is part of a multi-page thread which has, for the most part, been conducted between non-creationists. Pretty much everyone except you has been discussing the question of vestigiality in an evolutionary context. If you don’t want to do that, cool, but it’s a good idea to actually say so.
But you don’t need to infer an immune role to research it; you only need to hypothesize one. You seem to believe research on a question is impossible unless at least one person fervently believes in each possible answer, and that’s not the case. Someone who thinks the appendix is probably vestigial can still think of a new way to test that claim.
The literature looks a lot stronger than “speculations” to me…and of course they didn’t assume a vestigial nature before they knew anything about the structure. That’s a question to attack after you’ve got some data.
Do you realize the inconsistency there? You started by criticizing the claim that the appendix is vestigial, on the grounds that we don’t know it doesn’t have a function. Now you’re claiming that fetal teeth are vestigial, on the grounds that we don’t know they do have a function, and it’s just obvious that the whales don’t use them.
You may need to reread Schwab’s post. We have better evidence that the adult appendix is useless than for almost any other vestigial structure, because we cut it out of thousands of people and nothing bad happened. We don’t have evidence remotely that strong and direct for the uselessness of fetal whale teeth.
Um, that shows that that part of the definition does work. Because flippers aren’t “the same but less” than feet.
Creationists have a stock answer to this–God’s entitled to reuse a good part in various unrelated animals, just like a good designer would. If a given bone in a given location is helpful for locomotion in terrestrial mammals, and for copulation in marine mammals, then God simply chose to use it in both.
Wrong. Creationists are quite talented at suggesting alternate functions a vestigial structure might have. In the case of fetal teeth, AiG claims that “the teeth in the embryo function as guides to the correct formation of the massive jaws.” Silly? Sure. But how are you going to convince a creationist that it’s wrong, if you can’t even convince them we don’t need the appendix?
This is under the category of “Creationism”. Figure-it-out..
I did not say creationists will not try and weasel out. I know they do, but even most creationists do not buy into the AiG arguments about other fetal uses for teeth, hind-limbs, auricular musculature etc… They try and avoid these issues in all public debates as best they can.
This is an example of a response by you:
“Creationists have a stock answer to this–God’s entitled to reuse a good part in various unrelated animals, just like a good designer would. If a given bone in a given location is helpful for locomotion in terrestrial mammals, and for copulation in marine mammals, then God simply chose to use it in both.”
This, like your other responses, is a strawman. I was not talking about the fossil evidence of a supposed copulatory organ, I was talking about evidence for the vestigial nature using, 1, embryonic development of a hind limb that degenerates, 2 a fossil record that supports the prediction that whales once had hind limbs, and then odd gene expression that shows this element being expressed in a population that does not normally show such. It is the combo of the three lines of evidence I used as a whole that I expressed, not a strawman version of the “one” you did. Also, removal of the element, and the health of the organism afterwards does not need predict a vestigial nature. It can be vestigial, and seriously harm or kill an organism if removed.
Actually Pay attention to what I actually said…and to the fact that this is in the “creationist category”, and it is to that I replied, as I stated from the get go..
It’s also under the category of “Science.” Some of us are actually interested in the latter as well as the former.
Got any evidence to show that? Because when Kent Hovind talks about the uses for the whale pelvis, and Jack Chick writes about it in his tracts, it doesn’t sound to me like most creationists are particularly avoiding the subject in comparison to the appendix.
No, you weren’t talking about any of those. You said, “Same with the hip. It is not simply that there is a hip bone present with muscle attachments, it is the fact that buds start to develop there in the same manner as we see in terrestrial animals, and then, at the same time, we see the occasional hind-limb sprout from the region with a fully developed knee, which can either be reabsorbed, or kept in some cases. Why a thigh bone and knee would develop in an animal at a point that corresponds to what we see in terrestrial animals as being the pelvic region is a tad confusing to say the least in the view of special creation.”
On the contrary, “common design” explains that as well as it does anything.
Logic error. The second sentence is quite correct, but merely implies that being 100% safely removable is not necessary for vestigiality. That doesn’t mean that being 100% safely removable isn’t sufficient for vestigiality. Anything
It doesn’t appear that you’re even paying attention to what you said yourself, let alone what anyone else said, so I don’t see much point to continuing the conversation.