BIOL 150 Chapter Notes - Chapter 28: Paleozoic, Polyphyly, Proterozoic
Document Summary
Adaptive radiation - rapid evolutionary diversification within one lineage, producing many descendant species with a wide range of adaptive forms. Ancestral trait - a characteristic that existed in an ancestor. Background extinction - refers to the lower, average rate of extinction observed when a mass extinction is not occurring. Cambrian explosion - the adaptive radiation of animals. Cenozoic - divided into the paleogene, neogene, and quaternary periods. Cladistic approach - based on the principle that relationships among species can be reconstructed by identifying shared derived characters--synapomorphies. Convergent evolution - occurs when natural selection favors similar solutions to the problems posed by a similar way of making a living in different species. Derived trait - a characteristic that is a modified form of the ancestral trait, found in a descendant. Doushantuo microfossils - include tiny sponges and corals. Ecological opportunity - the availability of new or novel types of resources.
