Which Example Describes Mechanical Reproductive Isolation

Question

Which example describes mechanical reproductive isolation?
A) Two squirrel populations live on either side of a mountain range.
B) Two fly species have differently shaped genitals that prevent interspecies mating.
C) Two similar species of sunflowers bloom at different times of the year.
D) Individuals from two wildcat species produce infertile offspring when they mate.

Accepted Answer

Mechanical reproductive isolation refers to the physical or anatomical differences between species that prevent mating or fertilization. The example given in option B of two fly species having differently shaped genitals that prevent interspecies mating is the only one that fits this definition. The other options describe different types of reproductive isolation - geographical (option A), temporal (option C), and hybrid inviability (option D).