Human embryos have a developmental stage during which they have a tail and pharyngeal pouches (those pouches develop into gills in fish).How can we explain these characteristics of human embryos?
A)Human embryos need a tail and gills to breathe during development in the placenta.
B)Human embryos spend time in the water where tails and gills are useful.
C)Human embryos share a common ancestor who had gills.
D)Both A and B are correct.

Question

Quizplus · Accepted Answer

Human embryos have a tail and pharyngeal pouches because they share a common ancestor with fish that had these features. These ancestral traits have been conserved through evolution, although they have been modified and lost over time as humans adapted to life on land. Embryonic development follows a pattern that reflects this evolutionary history, even though the final form of the organism may look very different from its early developmental stages.

Human Embryos Have a Developmental Stage During Which They Have