AP BIOLOGY

Detailed explanation-1: -Fossils, anatomy, embryos, and DNA sequences provide corroborative lines of evidence about common ancestry, with more closely related organisms having more characteristics in common. DNA underlies the similarities and differences in fossils, anatomy, and embryos.

Detailed explanation-2: -Biologists often compare the sequences of related (or homologous) genes. If two species have the “same” gene, it is because they inherited it from a common ancestor. In general, the more DNA differences in homologous genes between two species, the more distantly the species are related.

Detailed explanation-3: -Evidence for common ancestry can be found in the fossil record, from comparative anatomy and embryology, from the similarities of cellular processes and structures, and from comparisons of DNA sequences between species.

Detailed explanation-4: -Fossils document the existence of now-extinct species, showing that different organisms have lived on Earth during different periods of the planet’s history. They can also help scientists reconstruct the evolutionary histories of present-day species.