EVERYDAY SCIENCE

Detailed explanation-1: -These shared genes preserve a record of an ancestor that they share with each other, but not with bacteria. Because genes change over time, the more similar the DNA of two organisms, the more recently they share a common ancestor. Observations from anatomy, fossils, and embryological development are all rooted in DNA.

Detailed explanation-2: -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-3: -Evidence for evolution: Molecular biology Like structural homologies, similarities between biological molecules can reflect shared evolutionary ancestry. At the most basic level, all living organisms share: The same genetic material (DNA) The same, or highly similar, genetic codes.

Detailed explanation-4: -Similarities can often be explained by common descent; features are considered homologous if they are shown to be inherited from a common ancestor. For example, although the arms of four-limbed vertebrates externally appear quite different, all have the same basic underlying skeletal and muscular pattern.

Detailed explanation-5: -Ancestral organism shared by two or more descendent lineages-in other words, an ancestor that they have in common. For example, the common ancestors of two biological siblings include their parents and grandparents; the common ancestors of a coyote and a wolf include the first canine and the first mammal.