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Purpose of Appendix Believed Found
CambodiaSam sent in this story, which opens: "Some scientists think they have figured out the real job of the troublesome and seemingly useless appendix: It produces and protects good germs for your gut.
That's the theory from surgeons and immunologists at Duke University Medical School, published online in a scientific journal this week.
For generations the appendix has been dismissed as superfluous. Doctors figured it had no function. Surgeons removed them routinely. People live fine without them.
The function of the appendix seems related to the massive amount of bacteria populating the human digestive system, according to the study in the Journal of Theoretical Biology. There are more bacteria than human cells in the typical body. Most are good and help digest food.
But sometimes the flora of bacteria in the intestines die or are purged. Diseases such as cholera or amoebic dysentery would clear the gut of useful bacteria. The appendix's job is to reboot the digestive system in that case."
I have studied little biology or medical subjects though I've read studies about this same sort of thing happening with asthma, polio & allergies. I think I've posted about this before but anecdotally I noticed there were no farmers who had allergies or asthma as I grew up and worked on farms with them. The young kids would play in hay and run around in the mud outside when it rained. So it seems that a problem with being an overly hygienic society today (as the article notes) is that we don't expose our young to these pathogens early on so they never adapt to them and suffer exposure to them later. This is why I recommend against anyone installing an air purifier in their home. It's a great idea--if you never plan on leaving your home.
I can't find the research but I thought a long time ago that a German study was done to find out why polio was "a middle class disease." If I recall they found that poor children were exposed to it since birth and rarely suffered from it since they were exposed to it always. The middle class children would be protected as infants but once exposed to it, their bodies would not be able to fight it. The upper class would take all costs to reduce exposure to it at all times--and they could.
Now this research is interestingly related in that appendicitis may be something that occurs due to our lack of exposure to diseases that destroy all the germs in our body (cholera & certain types of dysentery). Should something happen that would threaten this, our bodies respond poorly to it and the appendix flares up. As this article notes, appendicitis occurs less frequently in underdeveloped countries. Perhaps this is more reinforcement for the idea that protecting your children from germs is a double edged sword.
My work here is dung.
The abstract, for those who don't have access to the journal (article DOI doi:10.1016/j.jtbi.2007.08.032):
The human vermiform ("worm-like") appendix is a 5 to 10 cm long and 0.5 to 1
cm wide pouch that extends from the cecum of the large bowel. The architecture of the
human appendix is unique among mammals, and few mammals other than humans have
an appendix at all. The function of the human appendix has long been a matter of debate,
with the structure often considered to be a vestige of evolutionary development despite
evidence to the contrary based on comparative primate anatomy. The appendix is thought
to have some immune function based on its association with substantial lymphatic tissue,
although the specific nature of that putative function is unknown. Based (a) on a recently
acquired understanding of immune-mediated biofilm formation by commensal bacteria in
the mammalian gut, (b) on biofilm distribution in the large bowel, (c) the association of
lymphoid tissue with the appendix, (d) the potential for biofilms to protect and support
colonization by commensal bacteria, and (e) on the architecture of the human bowel, we
propose that the human appendix is well suited as a "safe house" for commensal bacteria,
providing support for bacterial growth and potentially facilitating re-inoculation of the
colon in the event that the contents of the intestinal tract are purged following exposure to a pathogen.
I, for one, welcome our bacteria-breeding appendix overlords.
? syntax error
I suppose you could poke equally as much fun back at the computer science community with: Virus? Is a computer the immune system? Fields of science borrow and share terms all the time. People seem to like the term 'reboot' despite it's origins being found in computers. I myself sometimes forget the pure origin of the word. The 'boot' part being from the bootloader of a system which plays a vital role in the bootstrapping process prior to the start of the operating system (if there is one installed). Do you think tailors are annoyed that we stole their bootstrap word?
Why nitpick terminology when everyone borrows it. Accept descriptive words, don't be prescriptive--I think that's what makes languages fun and interesting instead of boring, dry & dead.
My work here is dung.
On the evening of the sixth day of creation, God had an argument with his editors about what to do with some material that all agreed was clever but not an especially great fit. So they decided to move it to the appendix.
Gives a new meaning to the term "stack dump". I myself am currently suffering from a stop error. :-(
-Rob
Biblical fiscal responsibility
Just like leaving meat out in the sun "produces" flies? Didn't we sort all this out back in the 17th century or whatever? Oh wait, its CNN, that paragon of quality journalism.
I want to delete my account but Slashdot doesn't allow it.
Evolution doesn't approach the best solution, just the solution that's better than the others in existence at the time.
>"Evolution would have gotten rid of it if this part were useless."
Evolution takes time. Hence the darwin awards
Also, its a "moving target", since evolution alters the environment (predators, food chain, etc.), one consequence is the current "solution" is always sub-prime.
The purpose of the appendix to spontaneously kill you in a horribly painful way.
Unless you have access to surgeons. Yay modern medicine!
You can't take the sky from me...
Using openSUSE instead of Windows since 9th of October, 2007 and liking it.
When a computer is turned on, it needs to load some code to run. In order to do this, it needs some code to tell it which code to load. In order to load that code, it needs some code to tell it what to load, and so on. The solution is to have the computer metaphorically pick itself up by its bootstraps to get the first bit loaded. The code it then runs became known as the bootstrap, and later the term was corrupted to boot loader, and other variations.
I am TheRaven on Soylent News
Evolution would have gotten rid of it if this part were useless.
No. Evolution would have gotten rid of it if it caused a net increase in the risk of death between menarche and menopause (males simply don't matter here).
Now, we might presume at first glance that since appendicitis can kill, and a not-inconsiderable portion of the population will at some point get it. But the lower incidence in underdeveloped countries suggests that its modern danger to us may result largely from lifestyle; and, as we currently chop it out at the first sign of inflammation, we may also overstate the actual risk of death from appendicitis in the absence of treatment.
Evolution/God does their work quite well I guess.
You can believe what you want about a deity, and what mechanisms it put into place to run the universe. But beware of animism by ascribing "intent" to abstract statistical descriptions of phenomena.
Well, bacteria are the most populous living organisms in the world, and they're developing resistance to all our antibiotics, so its only a matter of time before we see stuff like ...:
[_] I for one welcome our bacterial scum pond overlords ... oh, they're ALREADY a cluster ... and drug resistant - I guess we're cluster-f$cked!
[_] I have no intestine, you ignorant clod scumbag!
[_] Imagine a beowulf cluster of
[_] All your base nucleotides belong to us
[_] In Soviet Russia antibiotics kill YOU!
Mind you, we're talking about a culture that still insists on doctor-shopping to get antibiotics for viral infections, and over-indulges in anti-bacterial wipes, plastics, etc., to the point of both compromising our own immune systems, and breeding super-bugs.
Evolution would have gotten rid of it if this part were useless.
It is not exactly true that evolution would get rid of a part that has become useless. Evolution through natural selection would tend to remove mainly deleterous (harmful) structures, but structures that are neither harmful nor helpful are masked from natural selection. To explain the loss of the vestigial structures, we must realize that the individual organism has only so many resources (energy, molecules, etc) with which to survive. This causes natural selection to select against structures that use up the organism's resources without contributing to its survival (for example in whales, who still have vestigial hips and leg bones, which serve no function and are much reduced in size).
This leads to the question of why the structure is still present. There are two major reasons why we would still observe the structure today: time and cost.
If natural selection only started working on removing the structure in recent time (geologically speaking), it would not be finished instantly in one generation, as natural selection works by tiny modifications that are build on generation after generation. Hence the canon of natural history: Natura non facit saltum (nature makes no leap).
A second possibility for its continued presence is that further reduction in its size or its total absence would be more disadvantageous the organism's fitness than its presence. This seems to be what the study is suggesting, that even though it is not used to the full extent it once was, there is some tiny function that is still useful enough to justify the resources the organism spends on it.
We are made wise not by the collection of our past, but by the responsibility for our future. -George Bernard Shaw
The appendix's job is to reboot the digestive system in that case.
So your appendix is run by Microsoft support.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Want to give your offspring the best chance?
1. Breastfeed. Not just for 6 weeks either. Worldwide average weaning age is 3-4yrs. U.S. is about the worst at this.
2. Let your kids eat dirt. No, don't encourage it. Just don't freak when it happens.
3. Be very conservative with immunizations. How many middle class US children are really going to get exposed to Hep? And since thermerisol has finally been removed from vaccination products, the autism rate has finally stopped exploding (despite the fact that studies show no link between the two).
4. LOTS of physical contact! Breastfed babies get this. It stimulates brain development.
5. Love the little knuckleheads despite everything.
6. Learn basic biology and medicine yourself. Your offspring, your responsibility. Knowledge and common sense go a long way towards health.
We're still learning about biology and medicine. Oh shit, you mean bacteria can evolve to become resistant to antibiotics, and that blanketing the population with antibiotics (antibaterical handsoap, anyone?) causes bigger problems than it solves? I've never heard of a staph infection from a home birth. When women give birth at home around all the same germs they are exposed to anyway, postpartum infections are almost nonexistent.
OTOH, I will take exception to the idea that there were no allergies and less sickness among rural populations 2 generations ago. There were. The difference is that those kids were just labeled "sickly" and often died back then. Is it a bad thing that those kids have a chance now?
All pass beyond reach of medicine. None pass beyond the reach of love.
From TFA:
And what about the foreskin?
now we need to go OSS in diesel cars
Of course earlobes are useful. I mean, what else could you possibly hang earrings off ... your privates?
Hal Spacejock: Science Fiction with Nuts
The metaphor predates CPUs by a good few decades. The machines for which the concept was invented were very early stored program computers. Originally, computers had their software hard-wired, and running a new program meant rewiring the computer. The next generation, starting with the Manchester Baby, stored their programs in the same way as they stored data and so encountered the problem of bootstrapping since they no longer had a hard-coded program. They had to have a simple program hard coded that would allow them to pick themselves up by their bootstraps and load the stored program. By the time microprocessors and things like the x86 BIOS were around the term was already old.
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Evolution will drop useless parts as well, just not as quickly since it doesnt effect survival at the time. ( where it may have at some point in the past ). Remember too, mating rituals are part of survival. Often in the animal kindgom if you arent as pretty as the competition you cease to contribute to the gene pool. Lobes and other apparent useless-but-neutral features may have been a 'pretty' factor 10 thousand years ago for us.
And since evolution never stops, you cant really predict when something like earlobs will disappear. It just hasn't happened YET.
---- Booth was a patriot ----
My high school biology teacher at an "excellent" public school told me that the function of the appendix in the olden days was to digest rocks and such that primitive humans might have digested by mistake. =)
The blurb posted on slashdot states that in the human body, there are MORE BACTERIA than there are HUMAN CELLS. Which would suggest that a minimum of 51% of the human body is made up of bacteria and only 49% (or less) of our body is made of things like . . . water, carbon and other . . . you know . . . human composition stuff.
One meaning of "more bacteria than human cells" means simply that there are a larger number of bacteria than they are human cells, not a larger mass of bacteria than human cells. For example, e. coli is about 1/100 the size of a human cell. So if there was an equal number of e. coli cells and human cells in the body, it would make the mass proportion of e. coli cells about 1% not 50%.
By the way, bacteria are also made of water, carbon and other ... you now ... organic composition stuff. Humans don't have a monopoly on that composition.
Your not-inconsiderable portion of the population is considerable - about 7%. Appendicitis does kill often if left untreated. Delay in diagnosis is the principle reason for mortality so to "chop" it off at the first sign of inflammation is usually a good idea. Spontaneous resolution of appendicitis is not something to wait for. Having a patient perforate in front of you is considered bad medicine in the US. If it does serve the purpose of protecting the bowel flora during bouts of cholera / dysentery, then it probably is superfluous in a developed country and will be selected against (esp in fertile women as appendicitis usually strikes people between 10-30.) I do wonder if it is able to salvage more bacteria when faced with antibiotics and if it helps repopulate the gut in developed countries after a pt takes a Z-pak or fluoroquinole for their "bronchitis."
Please don't read this and think that you or your loved ones should avoid an appendectomy if you need one. Nearly all appendectomies are performed on painfully sick people who are facing certain, slow, painful death without an appendectomy.
Does everything have to have a purpose? That's far too deterministic a philosophy for my tastes. Maybe the appendix doesn't have a purpose, is not part of a plan, has nothing whatsoever to do with survival of the fittest. Maybe it's just a quirk of intestinal development. Maybe its benign enough that there was no reason [sic] to cull it from the gene pool.
Don't blame me, I didn't vote for either of them!
In the old days, you might enter the bootstrap on a front panel (in the snow over your head uphill both ways). In it's simplest form a set of toggle switches connected to the address and data bus and a pushbutton to strobe the write line (yes, manually, CPU not yet running). Eventually, the bootstrap code started being placed in a ROM and instead of forcing an address into the program counter, it would go to a defined value when reset strobes (which the chipset does when the power supply stabilizes).
For that matter, when entered manually, the bootstrap program was likely just barely enough to load a second stage bootstrap from somewhere that would then load the OS.
Now get off my lawn :-)