Two closely related beetles are in the same location.They exhibit reproductive isolation, and they are both diploid.Biologists are arguing about which is more likely, that they evolved via sympatric or allopatric speciation.What statement presents the best argument?
A) Allopatric speciation is more parsimonious (and thus most likely) because sympatric speciation would require the populations evolving genetic differentiation despite gene flow.
B) Allopatric speciation is more parsimonious (and thus most likely) because sympatric speciation would require the populations being separated by a barrier, evolving genetic differentiation, and then coming back together.
C) Sympatric speciation is more parsimonious (and thus most likely) because allopatric speciation requires heterozygotes to be less fit than either homozygote.
D) Allopatric speciation is the only plausible means of speciation except in the case of polyploidy.
E) Sympatric speciation is the only plausible means of speciation except in the case of polyploidy.

Question

Quizplus · Accepted Answer

Allopatric speciation is considered more parsimonious because it involves populations becoming geographically isolated, which naturally limits gene flow, allowing for genetic differentiation. Sympatric speciation, on the other hand, requires genetic differentiation without physical barriers to gene flow, which is a more complex scenario.

Two Closely Related Beetles Are in the Same Location