A. Natural Selection is only one part of the theory of evolution. B. Theory explain natural phenomena based on observations C. Evolution states that all organisms on Earth have descended from a common ancestor
A. Fossil Record 1. Record of species that lived long ago 2. Ancient species are similar to current ones 3. Some species have remained unchanged for millions of years
B. Anatomy– physical bodies of current and extinct species may show relationships 1. Homologous structures – Anatomically similar structures inherited from a common ancestor
2. Analogous Structures- Can be used for a similar purpose but ARE NOT evidence of evolution. a. Similar traits can evolve independently b. bird wings and insect wings
3. Vestigial Structures– structures that are the reduced forms of functional structures in other organisms
C. Comparative Embryology 1. An embryo is an early pre-birth stage of an organisms development 2. Many vertebrates have similar stages while in the womb A. Pharyngeal pouches – we have “gills” guess embryo interactive guess embryo interactive
D. Comparative Biochemistry 1. Similar features in DNA, RNA, amino acids 2. The more similar the features the more closely related.
E. Geographic Distribution 1. Species are more closely related to species close to them geographically 2. Created field of biogeography– study of the distribution of plants and animals on earth
A. Adaptations Inherited traits Increase FITNESS Fitness = traits which lead to greater survival and/or reproduction B. Non-adaptations Not all features are adaptations
1. Camouflage– allows species to blend with their environment 2.Mimicry- one species evolves to resemble another one 3. Antimicrobial resistance— Bacteria have adapted to be resistant to antibiotics