Evolution | Page 2

The Fossil Record

Fossil record, history of life as documented by fossils, the remains or imprints of the organisms from earlier geological periods preserved in sedimentary rock. In a few cases the original substance of the hard parts of the organism is preserved, but more often the original components have been replaced by minerals deposited from water seeping through the rock. Occasionally the original material is simply removed, while nothing is deposited in its place; in this case, all that remains is a mould of the shape of the plant or animal.

Comparative Anatomy

Comparative anatomy has long served as evidence for evolution; it indicates that various organisms share a common ancestor. Also, it assists scientists in classifying organisms based on similar characteristics of their anatomical structures. Comparative anatomy supports Darwin's theory of descent with modification, also known as evolution. A common example of comparative anatomy is the similar bone structures in forelimbs of cats, whales, bats, and humans.