105. When comparing 2 populations of animals, which state most likely indicates
     they are the same species?
     A. They produce fertile offspring.
     B. They inhabit the same general area.
     C. Their outward appearance is similar.
     D. They consume the same type of diet.

A. They produce fertile offspring. In the world of biology, one of the classic ways to define species is through the concept of reproductive isolation. If two populations can mate and produce fertile offspring, it suggests they share enough genetic similarities to be considered the same species, bestowing them the magical stamp of “genetic compatibility!”

B. It’s important to note, however, that two populations might live in the same habitat or eat the same foods without being the same species. For example, many different species of birds might inhabit the same forest, but they have unique adaptations that keep them distinct. Always look beyond the surface and dig deeper when comparing different animals!