Question 16

[jimmytech3124]

Hi can somone please explain me this question/answer. i spent alot of time but cant seem to reason it out. i'd appriciate if somone could clarify. Thanks


The passage suggests that one result of interspecific interactions might be:


genetic drift within sympatric populations.[x]
genetic drift within allopatric populations.[x]
genetic mutations within sympatric populations.[x]
genetic mutations within allopatric populations.[x]

[kwon.denni6401]

I also had question about #16. I understand how the population must be allopatric but I do not understand how "genetic drift" or "mutation" fits into this question.

Genetic drift is the "process of change in allele frequencies that occurs entirely from chance" (wikipedia)

Interaction between two species that produce "random" changes in allele frequency doesn't seem to explain how one species affects the other. Mutation is the random "changes to the nucleotide sequence of the genetic material of an organism" (wikipedia)

How do random events explain how one species affects the other??

Thanks for the clarification

[asfi]

is genetic mutations ruled out because its more of a "survival of the fittest" situation? would choice a be ruled out because genetic drift doesn't occur between two different species?

[mybirdnest7483]

I thought genetic shift was caused by selective pressure.

I just ruled out mutation because there's no mutagen, but it's the selective pressure that's causing evolution.

[jellywing_2058]

Drift or mutation does fit in this question since the context says that the parasite and the host are in a race to co-evolve.

Also, a parasite is a living being that takes advantage of its host in order to survive. Usually, parasites harm the host; therefore the host must have a genetic drift in order to develop resistance against the parasite. As a consequence, the parasite must have a genetic drift as well in order to overcome the resistance developed by the host.

Quote: is genetic mutations ruled out because its more of a "survival of the fittest" situation? would choice a be ruled out because genetic drift doesn't occur between two different species?

No. Choice A makes sense; however the context talks about populations that do not live in the same territory. Also, as mentioned in the explanation, a mutation is a random change that occurs in an individual’s DNA which is most of the time bad for its survival. Therefore the answer cannot be a mutation.

[deblinak1531]

This question makes no sense, and there is no way to justify the answer unless we engage in slippery slope arguments.

First, the passage basically says that there are two outcomes to interspecific interaction: (1) genetic drift occurs in the local population (sympatric speciation) or (2) genetic drift occurs in the parasite population.

Insofar as there are TWO options (P2), the answer could be either A or B. Personally, I think A is a more direct answer.

This question should be changed.

[jellywing_2058]

As I mentioned before and as the explanation says as well, choice A cannot be right because the interaction is not sympatric but allopatric. This makes answer choice B the correct answer.