EVERYDAY SCIENCE

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: -Embryos of different species can have similarities that are not visible when the organisms are fully formed. Many of these similarities are homologous features. These features provide evidence that the species are related through evolution. embryos have homologous structures called pharyngeal arches, or gill arches.

Detailed explanation-3: -Similarities in structure among distantly related species are analogous if they evolved independently in similar environments. They provide good evidence for natural selection. Examples of evidence from embryology which supports common ancestry include the tail and gill slits present in all early vertebrate embryos.

Detailed explanation-4: -Explain why similarities in the early development of different species suggest that the species are related. It shows that by having similar body structures, they probably have a common ancestor. What type of evidence is the best indicator of how closely two species are related? DNA codes are the best.

Detailed explanation-5: -Evidence of an evolutionary common ancestor is seen in the similarity of embryos in markedly different species. Darwin used the science of embryology to support his conclusions. Embryos and the development of embryos of various species within a class are similar even if their adult forms look nothing alike.