GRE Subject Test: Biology : Understanding Divergent and Convergent Evolution

Study concepts, example questions & explanations for GRE Subject Test: Biology

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : Understanding Divergent And Convergent Evolution

Which of the following is an example of convergent evolution?

Possible Answers:

Two species merge together to form a single species

Two populations living in the same geographic region acquire enough differences to diverge into two separate species

A species regains a trait that an ancestor had previously lost

Two different species independently gain the ability to fly

Correct answer:

Two different species independently gain the ability to fly

Explanation:

Convergent evolution is the phenomenon by which two separate species evolve a shared trait. A classic example of this is that both birds and bats have evolved wings, but do not share a common ancestor prior to the development of this trait. Birds and bats developed their wings separately through completely unique mechanisms.

A population diverging into two separate species while residing in the same area describes the phenomenon of sympatric speciation. A species regaining a trait is an example of evolutionary reversal. 

Example Question #2 : Understanding Divergent And Convergent Evolution

An example of __________ is the speciation of Darwin's finches through the accumulation of many small, distinct traits.

Possible Answers:

artificial selection

divergent evolution

convergent evolution

parsimony

Correct answer:

divergent evolution

Explanation:

Convergent evolution is the phenomenon by which two species independently evolve a similar trait. An excellent example is the evolution of flight/wings in birds and bats, which do not share a common ancestor. Parsimony is a principle that guides scientific explanation toward simple terms, rather than eleborate principles. By parsimonious thinking, the simplest explanation is also the most likely to be true. Artificial selection is a form of evolution in which organisms are selected and bred for beneficial traits that would not necessarily be selected for in nature. Dog breeding and the production of numerous types of produce and grains are subject to artificial selection by humans (this is different from genetic modification).

Divergent evolution describes the accumulation of distinct traits that can lead to speciation events. A large population consists of a single ancestor species. Over time, different groups of the population come to inhabit different niches and develop traits for specialized inhabitance of that niche. As these changes accumulate, the population slowly develops distinct groups. When these groups can no longer reproduce due to some sexual barrier, a speciation event has occurred. This process aligns with the theory of evolution for Darwin's finches.

Learning Tools by Varsity Tutors

Incompatible Browser

Please upgrade or download one of the following browsers to use Instant Tutoring: