Support for the theory of evolution

Fossil Record Provides evidence of Earth's changing life The oldest fossil evidence of life consists of chemical traces in rocks from Greenland that are 3.8 billion years old Fossils of species that became extinct-species that no longer exist -help scientists reconstruct the past

Fossil Record

Fossil Evidence Fossil evidence supports the hypothesis that whales, which have no hind limbs, evolved from land-dwelling ancestors that had four limbs. Paleontologists digging in Egypt and Pakistan have identified ancient whales that had hind limb bones

Similarities in Structure Homologous Structure: similar structure found in more than one species that share a common ancestor -Suggests common ancestor

Similarities in Structure Vestigial Structure: remnants of structures that may have had important functions in an ancestral species, but have no clear function in some of the modern descendants For example, the whales of today lack hind limbs, but some have small vestigial hipbones probably derived from their four-footed ancestors Natural selection would favor the survival and reproduction of individuals with genes for reduced versions of those structures