BIOL 1F90 Lecture Notes - Lecture 23: Adaptive Radiation, Apoptosis, Hox Gene
Document Summary
Macro- large, can be seen with the naked eye. Compare and contrast pre-zygotic and post-zygotic isolating mechanisms. Compare and contrast the concepts of gradualism and punctuated equilibrium. Describe how the spatial expression of genes, such as bmp4 and gremlin, affects pattern formation. Explain the importance of hpx genes and the body plan of an animal species. A group of organisms that maintains a distinctive set of attributes in nature. Known number of species is about 1. 4-1. 6 million. Estimates of unidentified species range from 2-100 million. A single species may exist in 2 distinct populations that are in the slow process of evolving into 2 or more different species. Amount of separation time for 2 populations o o. May find situations where some differences are apparent but difficult to deicide if the 2 populations are truly different species o. Short time - likely to be similar and considered the same species. Long time - more likely to show unequivocal differences.