Charles Darwin's theory of evolution by natural selection, one of the

Can someone explain the solution to this question. I chose A over D.

Any answer?
I too choose A over D.
A is the only one that illustrates a case where 'survival of the fittest' is contested. Mating vs survival.
Correct?

nitzzi, Wonderwoman31 - I have tried to explain the situation. Hope it is helpful for you.

Guys, Let me attempt this question. Charles Darwin's theory of evolution and if you know it, do not refer to that info. Only thing we know about it is this

Pre-thinking - What I need to do is find an option that is verifying above given definition. on simple lines, I will evaluate that bird (or animal) with it in 100(or more/less) yrs ago. With time what evolution did to them.

Out of A and D, let see which one fits above info and Why?

A. Studies have shown that a type of male flycatcher (a bird) with an extra-long tail is more desirable to females as a mate than flycatchers with shorter tails, even though the longer tail hinders the bird's flying ability and makes it more vulnerable to predation. ---- Lets ask few question to analyze this. so long tail is cause of evolution or cause of genetics or any thing else of that bird. it would have been evolution if 1000 yr back this bird used to have a very small tail and now have a very large one. A female is selecting out of many on the basis of a physical trait. This can not be the example of above given definition.

D. A type of moth near London was observed to change from a population consisting mostly of light-colored moths to a population of mostly dark-colored moths over a period of 50 years as a response to darkening of rocks and trees in the area due to soot and smoke from London factories. ---- Evaluation impacted for sure. Let see it with an example. Let say 5000 yrs ago a chameleon dont need to change colour, but with change in environment, it adopt this thing some how. Hope you see how two situations are similar. and this one is for sure an example of this theory.

I chose A over D since D explains a situation in which a variant survived because it was best suited to. Dark colored ones were more suited, so they survived and bred more than the other variant and therefore we have more dark colored moths now. It does not explain how "survival of the most fitted one" was challenged or was insufficient.

Charles Darwin's theory of evolution by natural selection, one of the foundational concepts of modern biology, is often summed up by the phrase, "survival of the fittest." Many people interpret this phrase to mean that evolution always favors the organism that is best suited to survive in its environment, but this narrow interpretation is actually insufficient to explain many phenomena observed in nature.

Understand:
- evolution theory suggests that the evolution favours those that are well suited/adapted to the challenges right now or the ones expected in future.
- author's point: but there are certain phenomenons where the theory doesn't really explain the evolution. An evolution which actually had nothing to do with survival per se. But due to some other reason.

Which of the following, if documented in a scientifically valid way, is most likely to be an example of the phenomena mentioned above?
- we have to find such a situation in which the evolution was not because of adaptability or survival but because of certain other reason.


A. Studies have shown that a type of male flycatcher (a bird) with an extra-long tail is more desirable to females as a mate than flycatchers with shorter tails, even though the longer tail hinders the bird's flying ability and makes it more vulnerable to predation.
- this option tells us that females selected a mate that had certain traits compared to others... Now this actually exemplifies the survival or fitness aspect. If the females are actually selecting the supposedly weaker ones (in certain aspects) then the mates might actually be genetically stronger !! This is in line with evolution theory.

B. It has been documented among whales, birds, and terrestrial mammals that colder temperatures encourage the development of larger animals, because larger animals have a lower surface-to-volume ratio and are therefore better able to conserve heat.
- evolution theory

C. Farm animals bred by humans are generally larger, slower, and less intelligent than their wild ancestors.
- no relevance

D. A type of moth near London was observed to change from a population consisting mostly of light-colored moths to a population of mostly dark-colored moths over a period of 50 years as a response to darkening of rocks and trees in the area due to soot and smoke from London factories.
-this option tells us that there was A change not due to survival instincts but due to changes that the organisms had gone through because of an external source ,which had nothing to do with survival...

E. Male lions fight for control of prides, and thereby the capacity to reproduce, even though these fights can end in the death or maiming of the loser.
- evolution theory

[size=80][b][i]Posted from my mobile device[/i][/b][/size]

The question asks which option is more appropriate 'if documented in a scientifically valid way'.

Both options A and E relate to selection rather than 'survival of the fittest' in a scientific way.
Option A states females select the ones with the longer tail - (The flycatcher birds haven't evolved or in some sort of way changed their tails )
Option E states that the fight which the lions go through 'CAN' end in a death or injury (not that it will always) - this doesn't show any way of evolution (this is just their selectivity criteria)
Option D backs it up with the fact that the population of the 'light colored moths' have actually reduced and hence the population consists more of the 'Dark colored moths' because it is the environment due to which they have to adapt and change their respective characteristics (in this is case the color)

It specifically talks about the environment that a creature adapts to, mating is an instinct and A emphasises on the instinct. From "A" we can also derive that there is no survival threat to birds with shorter tails, they just don't get mates. Whereas, if the cause of moths becoming darker (as suggested in option D), is well documented and it's survival is attributed to darkening of trees and rocks then that becomes the perfect example for "survival of the fittest" or "adapting to your environment" because the environment itself has changed.

thanks for the explanation. that helped

Hello expert,
I think D indeed proves “survival of the fittest” because the moth changes its color to well fit its environment and camouflage to protect itself from the predators. So why D is correct?
Also, I went with C and could you help to explain C? Thanks.

I have narrowed the answer to A and D.

"Many people interpret this sentence to mean that evolution always favours the organism best adapted to survive in its environment, but this narrow interpretation is actually insufficient to explain many phenomena observed in nature."

For (A), this seems to me to fit the part some phenomena are not the best adapted to survive in the environment, however, it doesn't really say anything about evolution, we don't know if the long-tailed trait is growing or dying.

Hence, in my opinion (D) is the better option to say that evolution is influenced by the environment.

A. Studies have shown that a type of male flycatcher (a bird) with an extra-long tail is more desirable to females as a mate than flycatchers with shorter tails, even though the longer tail hinders the bird's flying ability and makes it more vulnerable to predation - No correlation between adaptive ability and evolution instead it is the opposite

B. It has been documented among whales, birds, and terrestrial mammals that colder temperatures encourage the development of larger animals, because larger animals have a lower surface-to-volume ratio and are therefore better able to conserve heat.- Very similar to A

C. Farm animals bred by humans are generally larger, slower, and less intelligent than their wild ancestors.(wrong)

D. A type of moth near London was observed to change from a population consisting mostly of light-colored moths to a population of mostly dark-colored moths over a period of 50 years as a response to darkening of rocks and trees in the area due to soot and smoke from London factories- Talks about adaptive ability and evolution (correct)

E. Male lions fight for control of prides, and thereby the capacity to reproduce, even though these fights can end in the death or maiming of the loser. - Not related

GMATNinja could you help us elaborate on this

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