Instinct, How does it play into evolution

[Exploited Class]

I understand evolution fairly well; I may not be a biologist but I get the basic understanding of, "If a mutation helps you have sex, live longer, repoduce more often, is a benefit in those forms" that you have a good chance of evolving.

What I don't understand and it has me slightly freaked out is instinct. How does it carry to the next generation, even without education? Where is it stored in DNA/Genes and within the brain. Does the brain just grow with that pattern of instinct already in there?

Now take my cat, it covers up its own poop and pee, nothing taught it that, it just knows to do it. Spiders are born without any adult figure and it knows immediatly how to spin a web, where to spin it and how to kill.

I can comprehend that if there is an intelligent bird out there that figured out going south is a good idea that it will reproduce more often because it is a benefit to go south. However I don't see how the next bird would know this, even if it learned it, how would that learned information get passed on. It would be like my mom figuring out a great way to drive, then I am born and I know how to drive.

I just don't get it.

[Thomas]

I'm no scientist, but I'd say it's just a type of nature that developes in the animal's brains. Sort of a developement on the normal natural thoughts to breathe and find food when hungry.

However to say this, then an animals instinct would have to derive from its brain stem, this is where it gets be, because the spinning a web is a conscious decision and is executed with careful precision, whereas the brainstem's actions are sub-conscious and we don't have control over it.

So I must say, I'm at a terrible loss to help you!

[LSD]

I can comprehend that if there is an intelligent bird out there that figured out going south is a good idea that it will reproduce more often because it is a benefit to go south. However I don't see how the next bird would know this, even if it learned it, how would that learned information get passed on.

Evolution doesn't work like that.

No bird "figured out" going south, rather it developed, as any trait does, out of genetic mutations. Those birds which developed the mutation that motivated them to fly south were much more likely to reproduce and so had children that had the same genetic mutation.

Eventually, due to a much higher survival rate, those birds with that mutation became dominant.

Instinct is just like any other evolutionary trait, it arises from mutation and perpetuates based on its interaction with natural conditions.

The interesting thing about behavioural traits as opposed to physiological ones is how they interact with learned and conscious behaviours.

In the case of flying south, the bird isn't just blindly "following orders", it feels that it is getting cold and both instinctively and because of childhood experience, moves south. Many birds follow their parent early on and so learn at a young age to fly south every year. The bird also notices that as it keeps moving south, it tends to get warmer. This operant reinforcement only strengthens the behaviour.

In the end, the brain is just an organ like any other. Specifc neuron patterns that lead to specific knowledge and behaviour are just as phyiscal as specific cell patters that lead to a kidney.

The same evolutionary process created them both.

[Clarksist]

No bird "figured out" going south, rather it developed, as any trait does, out of genetic mutations. Those birds which developed the mutation that motivated them to fly south were much more likely to reproduce and so had children that had the same genetic mutation.


Wait so do you think that if given the time, people with the OCD of washing their hands often end up being cleaner and end up producing more and the OCD remains?

If not I don't quite understand your meaning.

[LSD]

Wait so do you think that if given the time, people with the OCD of washing their hands often end up being cleaner and end up producing more and the OCD remains?

There are a couple of problems with that analogy.

One, OCD is not entirely genetic.

Two, OCD is not a benneficial disorder. Most people with that form of Obsessive Compulsion do not actually end up being cleaner, they just end up damaging themselves. Furthermore, they tend to become socially isolated and hence are less likely to propagate their genes.

But if, hypotheticaly, there was a genetic mutation that did lead to better hygiene with no adverse effects, it is indeed more than likely that, given enough time, it would become a dominant trait within the species.

At least that's how it would work in most species. But because of the nature of human society, a genetic predisposition for hygiene wouldn't really be that much of a bennefit.


If not I don't quite understand your meaning.

Behavioural traits evolve in the exact same way as physiological ones: the nonrandom survival of randomly variant mutations.

More Lamarckian views have been thoroughly discredited (for the most part).

[Severian]

Originally posted by Exploited [email protected] 7 2005, 09:08 PM
Where is it stored in DNA/Genes and within the brain.
Some genes have been identified as controlling instinctive behavior in fruit flies for example; many others are stilll unknown. That's true of other inherited traits as well; we know some of the genes that control body structure for example but not others.

But it's not necessary for us to identify the gene, in order for natural selection to work on it. Darwin didn't know about genes at all. But he was able to explain that if a behavior is inherited, then natural selection can work on it like any other inherited trait. If it's learned, then it has nothing to do with Darwinian evolution. If it's partly inherited and partly learned, natural selection can work on the inherited part.

In the way LSD's explained. Darwin gives some examples in "Origin of Species" (http://www.bartleby.com/11/8003.html)

And as Darwin explained, the same process is used consciously by breeders to produce different instincts in domestic animals, especially the different breeds of dogs. Dogs with the desired behaviors were chosen to breed the next generation. This was continued for many generations, and the result was the different hunting and herding behaviors, and differing temperaments of different breeds of dogs.

[pastradamus]

There is no Biological Study of Instinct to speak of. Its more a psycological Study.

Instinct Was best explained to me by my old music teacher Who was also a Bachelor of psycology & a MENSA member.
He Picked up a stick and pretended to strike me with it before I ducked and covered my face in a sub-conscious reflex.

[Exploited Class]

Sorry I didn't reply back earlier on my own thread, busy the last few days.

Well the explinations clear this up a bit for me and reading the article by darwin helped a little, although some of it wasn't exactly clear.

A cat covers its own waste after it is done, I can't imagine that a gene mutation got a cat to do that or any other animal and I think this is where I am having issues. I see that it is a benefit for the animal to do so, but I don't see how a gene did that. I believe this is where I am running into problems, more of a what makes a thing a thing, the genes or the the brain....Am I me or am I genes?

So what instincts do we as people have at this point?
Flight or Fight
Self Survival (which we can overcome)

And Yeah I did think about the whole "breeding of dogs for temperment" idea.

[codyvo]

I too am boggled by how exactly the gentic structure of an animal can impact it's physical behaviour. But I would like to know, hypothetically: if a tribe of early humans traveled, say, west for better land, and their kids did the same, and theirs, and theirs and so on. When their is no more land west would they still try to go west?

I think the answer to this is the answer to everything else, insticts are practical. The birds fly south to stay warm, and so if their were a climate change then they would no longer fly south, because it would no longer be practical.

This is just my take on it, I am not positive, in fact I am very doubtful but it is a very interesting topic.

[LSD]

A cat covers its own waste after it is done, I can't imagine that a gene mutation got a cat to do that

Nonetheless, that's what happened.

Obviously it didn't happen "all at once", rather it is the gradual resulting combination of various benneficial mutations.


I believe this is where I am running into problems, more of a what makes a thing a thing, the genes or the the brain....Am I me or am I genes?

Well, what is "you"?

All that "you" are is the combination of your genetics and your environment. Your "personality" developed out of the combination of those interacting factors. Your brain developed based on your DNA. The neuronic imprint on this brain then changed as it encountered various enviornmental conditions.


I too am boggled by how exactly the gentic structure of an animal can impact it's physical behaviour. But I would like to know, hypothetically: if a tribe of early humans traveled, say, west for better land, and their kids did the same, and theirs, and theirs and so on. When their is no more land west would they still try to go west?

They might, they might not.

But if they did, it would not be the result of instinct, but rather of society.

That is, if you are taught all your life that you must move west ...you probably will. But that is not instinct, it's just education.

Instincts do not result from directed actions. I.E., no bird "figured out" flying south. Instinct, by definition, are the result of random mutations, those which proved to be benneficial to survival. Lamarckian views of instinct tranference have simply not panned out.


The birds fly south to stay warm, and so if their were a climate change then they would no longer fly south, because it would no longer be practical.

Many of them probably still would, but enough would have weak enough genetic instincts that they would be able to consciously overpower it and not fly south.

Eventually, the birds that still flew south would die out (because it was too cold), but those that did not will survive. Their genetics would then become dominant. That's how evolution works!

[Severian]

Originally posted by Exploited [email protected] 14 2005, 10:03 PM
I believe this is where I am running into problems, more of a what makes a thing a thing, the genes or the the brain....
Since the genes program the structure of the brain, why do you think this is counterposed?

(Of course there are environmental influences on the brain as well, but we're talking about instinct not learning here.)

[Severian]

Originally posted by [email protected] 14 2005, 10:52 PM
if a tribe of early humans traveled, say, west for better land, and their kids did the same, and theirs, and theirs and so on. When their is no more land west would they still try to go west?
Humans aren't controlled by instinct to the same degree; learned behavior has a larger role. Including culture; a habit of traveling west would be a cultural trait not an instinct. Cultural traits can also survive after their original purpose has died, but that's another subject...anyway, they can change much more quickly than genetic traits.


I think the answer to this is the answer to everything else, insticts are practical. The birds fly south to stay warm, and so if their were a climate change then they would no longer fly south, because it would no longer be practical.

Do you know of some observation to support this? In science you can't go on just whatever seems likely to you.

If their behavior could change quickly, or because they reasoned out on some level that it wasn't practical, then it wouldn't be an instinct. Instinct is inborn, genetically programmed behavior. Not learned behavior.

Plenty of animals try to migrate instinctively even though their instincts are no longer appropriate to a changed situation. Think salmon trying to migrate through a dam turbine. Those salmon won't pass on their genes for that instinct of course.

If all instincts and "everything else" were always practical, that would actually be evidence for creationism; only an omniscient Designer could arrange everything perfectly. It's the many flaws and impracticalities of living things which prove evolution. All the things like the panda's thumb, or our carpal tunnels and lower backs, that would be poorly designed....if they were designed at all.

[amos]

Cats covering their waste could be any number of things, ie less diseases spread through populations which cover their waste, enabling them to breed more successfully, or it makes it harder for predators to find them, or any number of other benefits which I can't think of at the moment.

Or possibly its a residual of some other behaviour which served to improve the chances of a cat breeding, the necessity for which has long since gone the way of the Dodo, leaving only the behaviour behind.

Don't forget we're talking about things happening over large numbers of generations (in the high thousands or more) for traits/mutations to become dominant.


Cheers
Amos