Question

The chart below shows three different stages of embryonic development for three different animal species.

Stages of Development of Three Animal Species



The earliest stage in the chart appears very similar for all three species. For example, all three embryos at this stage have gill slits and a large embryonic tail.

What do these similarities most likely indicate?
A.
All three species share a distant common ancestor.
B.
All three species evolved in the past 100 years.
C.
All three species look very similar as adults.
D.
All three species evolved from a single mammalian ancestor.

Answer 1

A. All three species share a distant common ancestor.

Explanation: Similar early embryonic structures (like gill slits and tails) are evidence of common descent — conserved developmental stages inherited from a distant common ancestor.