AP BIOLOGY

Detailed explanation-1: -The fossil record Fossil remains have been found in rocks of all ages. Fossils of the simplest organisms are found in the oldest rocks, and fossils of more complex organisms in the newest rocks. This supports Darwin’s theory of evolution, which states that simple life forms gradually evolved into more complex ones.

Detailed explanation-2: -The fossil evidence definition refers to the evidence of bacteria, animals, and plants that lived in the past. Fossil evidence is used to determine what the organism was, when it lived, and what major events it experienced during its lifetime.

Detailed explanation-3: -Comparative Embryology 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-4: -Five types of evidence for evolution are discussed in this section: ancient organism remains, fossil layers, similarities among organisms alive today, similarities in DNA, and similarities of embryos.