Question

Which pattern of development among vertebrates is evidence that they share a common ancestor? A. All vertebrates have a vestigial structure called gills. B. All vertebrate embryos have pharyngeal pouches during development. C. All vertebrates have tails as both embryos and adults. D. All vertebrates have identical embryos but differences among structures as adults

Answer 1

Answer: B. All vertebrate embryos have pharyngeal pouches during development.

Pharyngeal pouches are a common feature of vertebrate embryos, indicating that all vertebrates share a common ancestor. This is because the pouches are a remnant of the gill slits that were present in the ancestral vertebrate, and are passed down through the generations. The presence of these pouches in all vertebrate embryos is evidence of their shared evolutionary history.