ANT101H5 Lecture Notes - Allele Frequency, Macroevolution, Mutation
Document Summary
Analogies - structures that are superficially similar: share a similar function, built from different parts, do not pass through similar stages during embryonic development, organisms do not share a common ancestor, homoplasy: process that leads to analogy. Homologies - structures possessed by 2 different organisms that arise in a similar fashion: pass through similar stages during embryonic development, organisms that share a common ancestor, may serve different functions. Microevolutionary forces small changes in allele frequencies acting on the human gene pool. Vs macroevolution - appearance of new species due to many generational changes in allele frequencies. Divergent: a single ancestral species gives rise to 2 or more descendant species, physical & social barriers. Convergent: two phylogenetically unrelated organisms develop greater similarities, similar environments. Systematics: traditional approach, categorize organisms based on homologous traits. Cladistics: determine ancestral versus derived (modified) homologous traits to determine lineage, clade: a group of organisms with a common ancestor.
