Evolution question

[ScottySatan]

Why the heck did we evolve capsicum receptors in our buttholes? What possible selective advantage can that bring?

Ouchie!

 

[Neo Deist]

God has a sense of humor. Same reason we fart.

 

[beenherebeforeagain]

Well, I can't think of any obvious reason it would be selected for, but it could be a side effect of some other beneficial adaptation...the sensitivity isn't necessary, but some related trait is selected for by evolution.

Actually, here's a scenario: those without the sensitivity upon exit are less likely to realize that they've eaten something that is, for all intents and purposes, a poison, than those who do have the sensitivity. Those with, realize "Oh, gee! Those peppers I just ate not only hurt my mouth and throat, made my stomach up, but also hurts like the dickens on the way out. Maybe I should avoid those in the future!"

Assuming, of course, that heat is a bad thing...maybe those with sensitivity realize that it's a good thing...

 

[sun rise]

As usual, the internet, source of all wisdom and truth in the universe, provided the answer about why it hurts. Why it evolved is a question for another day.

Capsaicin is also not broken down (at least completely) by digestion and hence what exits later can still contain a reasonable amount of the chemical. And where the lining of the GI tract gives way to normal skin again, at the anus, there are large numbers of capsaicin receptors. As a result you have the killer combination of a sensitive mucosal surface "seeing" a reasonable does of capsaicin, so you get ring sting.
http://www.thenakedscientists.com/forum/index.php?topic=20185.0

 

[Guy Threepwood]

Well, I can't think of any obvious reason it would be selected for, but it could be a side effect of some other beneficial adaptation...the sensitivity isn't necessary, but some related trait is selected for by evolution.

Actually, here's a scenario: those without the sensitivity upon exit are less likely to realize that they've eaten something that is, for all intents and purposes, a poison, than those who do have the sensitivity. Those with, realize "Oh, gee! Those peppers I just ate not only hurt my mouth and throat, made my stomach up, but also hurts like the dickens on the way out. Maybe I should avoid those in the future!"

Assuming, of course, that heat is a bad thing...maybe those with sensitivity realize that it's a good thing...

Why the heck did we evolve capsicum receptors in our buttholes? What possible selective advantage can that bring?

Ouchie!

well this topic might belong in the joke section! but the similar problem comes up with natural selection of many dubious advantages


We could maybe hypothesize a theoretical technical advantage of a capsicum sensitive butt in certain scenarios.. but if it is not such an advantage, as to significantly increase chances of reproduction in an individual, over and above all other individual strengths and weaknesses, then zero natural selection has taken place for this. At what point in natural history was this such a significant advantage, as to cause a whole race of butt-sensitives to rise up and entirely overthrow the inferior numb butts?!

 

[beenherebeforeagain]

as long as there isn't a severe negative consequence of the trait (that is, those that inherit won't reproduce), there is no reason why some otherwise apparently useless trait would be passed on...especially if it is somehow linked to some trait that increases survival.

Let me repeat, not every trait necessarily has to have a selective advantage for survival, and insisting that they must is just wrong. Evolution is random.

 

[ScottySatan]

Let me repeat, not every trait necessarily has to have a selective advantage for survival, and insisting that they must is just wrong.

Overwhelming evidence says that any trait that requires an organism to build something that requires effort yet gives no benefit does go away given sufficient time. Speciation events have actually been timed based on the loss of unnecessary dna (see the work of Ken Wolfe for example).

So, I was thinking that capsicum receptors require effort to build...

 

[ScottySatan]

At what point in natural history was this such a significant advantage, as to cause a whole race of butt-sensitives to rise up and entirely overthrow the inferior numb butts?!

That's my question. In every other case, an unpleasant sensation like that means you're eating poison. But peppers aren't.

 

[beenherebeforeagain]

That's my question. In every other case, an unpleasant sensation like that means you're eating poison. But peppers aren't.

And how do the nerves in the body know that?

 

[ScottySatan]

And how do the nerves in the body know that?

Know what, that I'm eating poison?

 

[beenherebeforeagain]

Know what, that I'm eating poison?

How does your body know that you aren't eating poison? The body knows that it appears to be like a poison, but how could it know that it's an almost poison? Should it err on the side of not letting you know, just because it isn't immediately killing you?

 

[ScottySatan]

I don't really know what you're trying to argue, but I didn't say anything that I care to argue about.

 

[beenherebeforeagain]

I don't really know what you're trying to argue, but I didn't say anything that I care to argue about.

okay, then...

 

[ChristineM]

That's my question. In every other case, an unpleasant sensation like that means you're eating poison. But peppers aren't.

Perfume has the same effect, coco channel once said you should dab a little perfume everywhere you want to be kissed by your man. Damn that hurts.

 

[Milton Platt]

Why the heck did we evolve capsicum receptors in our buttholes? What possible selective advantage can that bring?

Ouchie!

No such thing as Capsicum receptors. Actually, it's capsaicin that is the culprit and it binds to the receptors that tell your body that it is being burned, that's why you get that sensation. Just eat lots of ice cream and you will be fine......well, not really, but you'll enjoy the ice cream.

 

[Jake1001]

The computer simulator having some fun with us.

Why the heck did we evolve capsicum receptors in our buttholes? What possible selective advantage can that bring?

Ouchie!

 

[crowfeather]

Why the heck did we evolve capsicum receptors in our buttholes? What possible selective advantage can that bring?
Ouchie!

Let me guess...
Scientists 'discovered' that this is what they are.
Probably it will eventually come to light that they are actually scent-diminishers.
Someone able to see the obvious will probably be the one to notice first.