BIOL 180 Chapter Notes - Chapter 6: Long Term Ecological Research Network, Flowering Plant, Proterozoic

• School: UW
• Department: Biology
• Course: BIOL 180
• Professor: H E R R O N, J O N

Document Summary

The two most compelling types of evolutionary events are: periods when species originate and diversify rapidly, periods when species go extinct rapidly. Adaptive radiation - occurs when a single lineage rapidly produces many descendant species with a wide range of adaptive forms. May be observed as the sudden appearance of related, diverse species in the fossil record, or it may be inferred by phylogenetic analysis. Three hallmarks of an adaptive radiation: species is a monophyletic group, species speciates rapidly, species diversi ed ecologically, into many niches. Niche - a range of conditions that a species can tolerate and the range of the resources that it can use. Factors extrinsic (external) to organisms, such as favorable new conditions in the environment. Factors intrinsic to (within) organisms, such as the evolution of key morphological, physiological, or behavioral traits. Ecological opportunity - marked by the availability of more resources or new types of resources - has driven a wide array of adaptive radiations.