Question

what is the most likely reason that horses and mountain goats have hooves?
○ they have homologous structures because they have a common ancestor.
○ they have analogous structures because they have a common ancestor.
○ these are vestigial structures in both animals because they are not used.
○ these are similar structures due genetic mutations.

Explanation:

To solve this, we analyze each option:

• Option 1: Homologous structures are similar due to common ancestry. Horses and mountain goats (both mammals) likely share a common ancestor, and hooves as homologous structures fit.
• Option 2: Analogous structures are similar due to similar function (convergent evolution), not common ancestry. Eliminate.
• Option 3: Vestigial structures are unused/reduced. Hooves are functional (e.g., for movement), so not vestigial. Eliminate.
• Option 4: Genetic mutations alone don't explain this shared structure; common ancestry (leading to homologous structures) is more likely. Eliminate.

Answer:

A. They have homologous structures because they have a common ancestor.