AP BIOLOGY

Detailed explanation-1: -Homologous features If two or more species share a unique physical feature, such as a complex bone structure or a body plan, they may all have inherited this feature from a common ancestor. Physical features shared due to evolutionary history (a common ancestor) are said to be homologous.

Detailed explanation-2: -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.

Detailed explanation-3: -Molecular similarities provide evidence for the shared ancestry of life. DNA sequence comparisons can show how different species are related. Biogeography, the study of the geographical distribution of organisms, provides information about how and when species may have evolved.

Detailed explanation-4: -Common descent is an effect of speciation, in which multiple species derive from a single ancestral population. The more recent the ancestral population two species have in common, the more closely are they related.