BIOLOGY 1M03 Lecture Notes - Lecture 1: Multicellular Organism, Insular Biogeography, Body Plan
11 Dec 2015
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Document Summary
Case study: adaptive radiation, then mass extinction of cichlids in. Developing a large database of dna sequences from the same region of the genome. Are instances of rapid diversification of a lineage accompanied by ecological diversification: e,g, darwin"s finches, very rapid speciation that arrived from a common ancestry. Adaptive radiations can be triggered by ecological opportunity and morphological innovation: ecological niches, allows them to access things that previously could not be, e. g. feathers in birds allows them to enter a new realm. May include high diversity of species spectacular divergence of specialization, or both. An adaptive radiation is the differentiation of a single ancestor into an array of species that inhabit a variety of environments and that differ in traits used to exploit those environments . Criteria to detect adaptive radiation: common ancestry, phenotype-environment correlation, trait utility, rapid speciation. Rapid speciation can be coupled quickly that the true phylogeny can not be pinpointed (very close and quick separation)
