JAMB Biology 2002 Question 25

Question 25

Evolution

The structure that is common in the embryos of mammals, amphibians, birds, fishes and reptiles and which is an evidence of their common ancestry is the

A.eye
B.chorion
C.allantois
D.gill-slits

Show the answer and explanation

Answer: D (gill-slits)

Explanation

All vertebrate embryos develop gill slits (pharyngeal clefts) at an early stage. This shared feature points to a common fish-like ancestor.