BIOLOGY 1M03 Lecture Notes - Lecture 5: Pipidae, Dusky Seaside Sparrow, Genetic Drift
5 Apr 2016
School
Department
Course
Professor
Document Summary
Biologist commonly use the following three approaches to idenify species: the biological species concept, the morphospecies consept, the phylogeneic concept. A species is deined as an evoluionarily independent populaion or group of populaions. Gene low homogenizes geneic variaion amount populaions so evoluionary independence starts with a reducion of cessaion of gene low. If the gene low between populaions stops, natural selecion, geneic drit, and mutaion begin to act on populaions independently. Allele frequencies and other characterisics of these independent populaions can become disinct species. The biological species concept bsc assigns individuals to the same species if they actually or potenially interbreed. Postzygoic isolaion: prevents gene low ater the zygote is formed: hybrid viability: hybrid ofspring do not develop normally and die as embryos, hybrid sterility: hybrid ofspring mature but are sterile as adults. Prezygoic isolaion occurs when individuals of diferent species are prevented from maing: ex.
