BIOL 1202 Chapter : Chapter 22
Document Summary
We all came from a common ancestor but modified over time - descent with modification. Darwin- we all came from a common ancestor. Perceived unity in life , with all organisms related through descent from an ancestor that lived in the remote past. As the descendants of that ancestral organism spilled into various habitats over millions of years, they accumulated diverse modifications or adaptations that fit them to specific ways of life. evolution- two main ideas: change! Over time of the genetic composition of a population: descent of modern organisms with modification from pre existing organism. Accumulation of inherited characteristics that enhanced organisms ability to survive in specific environments. Bodies of living organisms a modified through the use or disuse of parts. These modifications are inherited by offspring (example of giraffe) Gradualism- slow natural forces(wind, water, earthquakes, volcanoes) caused geological formations (not catasrophes) Uniformitarianism - the mechanisms of change are constant over time.