AP BIOLOGY

Detailed explanation-1: -Similarities in embryos are likely to be evidence of common ancestry. All vertebrate embryos, for example, have gill slits and tails. All of the embryos in Figure 9.3. 4, except for fish, lose their gill slits by adulthood, and some of them also lose their tail.

Detailed explanation-2: -Similarities in embryos are evidence of common ancestry. All vertebrate embryos, for example, have gill slits and tails (see the Figure below). Most vertebrates, except for fish, lose their gill slits by adulthood. Some of them also lose their tail.

Detailed explanation-3: -All vertebrate embryos have gill arches, notochords, spinal cords, and primitive kidneys.

Detailed explanation-4: -Similar anatomy across different species highlights their common origin and can be seen in homologous and vestigial structures. Embryology provides evidence for evolution since the embryonic forms of divergent groups are extremely similar.

Detailed explanation-5: -Embryology is important to understanding a species’ evolution, since some homologous structures can be seen only in embryo development. For example, all vertebrate embryos, from humans to chickens to fish, have a tail during early development, even if that tail does not appear in the fully developed organism.