Survival of the Fittest?

[unworthyone]

I'm a bit confused now.

Do traits tend to survive because they are the strongest traits, meaning, they have more muscle?

or....

Do traits tend to survive because they give the host organism a better chance for survival?

What the heck is meant by that? What is the cause of survival of the fittest?

 

[secularfuture]

Oh no! Not ANOTHER evolution post!

"Do traits tend to survive because they are the strongest traits, meaning, they have more muscle?"

In a way, yes. "Mother nature" keeps what is most useful, and gets rid of what isn't. "She" also refines us, all the time (evolution hasn't stopped) to make us better for our environment.

 

[seebs]

Okay, imagine that you have two kids, who are mostly identical. One of them is 90% likely to die before reaching reproductive age; the other is 20% likely to die before reaching reproductive age.

Which of them do you think will have more children?

 

[LewisWildermuth]

One would think that by now you might have bothered to open atleast an intro to basic biology book Worthy...

A trait survives evolutionary wise because it either does not hinder or helps the organism possesing said trait to survive and reproduce.

Now this only applies to traits that are incorperated with the sex cells or gammedes <sp?>. Any mutations that appear elsewhere will not be passed on and thus not selected.

 

[Nathan Poe]

Originally posted by unworthyone
I'm a bit confused now.

Do traits tend to survive because they are the strongest traits, meaning, they have more muscle?

or....

Do traits tend to survive because they give the host organism a better chance for survival?

What the heck is meant by that? What is the cause of survival of the fittest?

The second one, with an addition. Traits that survive are the ones that give the host organism a better chance of survival and breeding in its current environment.

Whatever the case, beneficial traits give the organism a better chance not only to survive, but to find a mate and breed, thus passing on its traits to the next generation. Organisms with harmful traits tend to die ( usually from environment or predators) early off, before they breed.

 

[secularfuture]

"The second one, with an addition."

Actually - its more or less both of them.

 

[Pete Harcoff]

Originally posted by unworthyone
What is the cause of survival of the fittest?

Everything harmful to an organism's survival. Predators, competition for food, disease, etc...

Survival of the fittest is a bit of misnomer (and usually leads people to think "bigger and stronger"). I prefer "survival of the best-adapted".

 

[unworthyone]

Originally posted by seebs
Okay, imagine that you have two kids, who are mostly identical. One of them is 90% likely to die before reaching reproductive age; the other is 20% likely to die before reaching reproductive age.

Which of them do you think will have more children?

I'm sorry Seebs but that is just confusing. They both could have kids, the 20% may never have any, so I'm gonna need more then that.

 

[unworthyone]

Originally posted by LewisWildermuth
One would think that by now you might have bothered to open atleast an intro to basic biology book Worthy...

I have and I get different responses, hence the question meanie.

A trait survives evolutionary wise because it either does not hinder or helps the organism possesing said trait to survive and reproduce.

Why would it survive because it helps? How does the organism recognize it is being helped?

 

[Pete Harcoff]

Originally posted by unworthyone
How does the organism recognize it is being helped?

It breeds before it dies.

 

[secularfuture]

unworthyone,
Nathan Poe &amp; Pete Harcoff pretty much explained it the best, so far.

 

[RufusAtticus]

The traits that survive are the ones that get passed on. If there is competition between traits, then the one more likely to get passed on is the one that survives. This is what is meant by a trait's "fitness."

The process of evolution is simply the imperfect replication of the ability to successfully replicate.

 

[unworthyone]

Originally posted by Pete Harcoff
It breeds before it dies.

So its really just keeping some traits that are not harmful. Anything else&nbsp;the&nbsp;host&nbsp;just lets it go if the trait can survive on its own.

 

[seebs]

Originally posted by unworthyone
So its really just keeping some traits that are not harmful. Anything else&nbsp;the&nbsp;host&nbsp;just lets it go if the trait can survive on its own.

Something like. In reality, "harmful" and "not harmful" is often not an either-or thing. There's a gene where one copy of it makes you immune to malaria, and two copies give you sickle-cell anemia. Is that gene "harmful" or "helpful"? A bit of each.

 

[Pete Harcoff]

Originally posted by unworthyone
So its really just keeping some traits that are not harmful. Anything else&nbsp;the&nbsp;host&nbsp;just lets it go if the trait can survive on its own.

Like seebs said, the differentiation between harmful and not harmful isn't quite black and white. What is harmful in one environment can be beneficial in another.

Human skin colour is an example of this. People with dark skin typically live in very hot, sunny environments (like Africa) and are exposed to more UV radiation than people who live in cooler environments (like Northern Europe). Dark skin acts as a protection against UV rays, to prevent things like skin cancer.

At the same time, a certain amount of exposure to UV rays is necessary for Vitamin D production. Hence, people living in cooler climates require lighter skin because they are exposed to fewer UV rays.

However, if you were to transport a dark-skinned person to Northern Europe and a light-skinned person to central Africa, their skin colour adaptations would work against them. The dark-skinned person would likely end up with Vitamin D deficiency (unless supplemented from another source), and the light-skinned person would get burned and probably wind up with skin cancer (unless they used lots of sunscreen).

Hope that helps explain things a bit.