8 Convergent EvolutionDescribes the independent evolution of similar features in different species.Example – wings
9 Different means of obtaining evidence to create Phylogenetic trees and cladograms 7 Definitions
10 DefinitionsHomoplastic evolutionary changes: acquisition of a similar form or structure between species of different lineages as a result of convergent evolutionBiogeography: the study of the geographical distribution of species and their evolutionary relationships. Species appear to have colonized island habitats from mainland areas and then been modified by natural selectionFossil Record: the fossilized remains of organisms provide a historical record of life on earth. Reveals the vast time scale over which the process of evolution has occurred
11 Homology: structures in closely-related species have been a similar underlying structure that appears to have been modified by natural selection in different environmentsAnalogy: Structures in distantly-related species have no similarity in underlying structure but have a similar function. These structures appear to have evolved under natural selection in similar environments.Embryology: similarities and differences in embryological stages indicate evolutionary relationships among organisms.Molecular biology: similarities and differences in the structures of DNA and protein indicate evolutionary relationships among organisms.
12 Phylogenic trees and cladograms are constantly being revised New research with biological dataNew mathematical and computational ideasCurrent knowledge compared to emerging knowledge
13 HARDY WEINBERG EQUILIBRIUM Requirements for H/W equilibriumNo mutation takes placeNo migration (emigration or immigration)Random matingVery large populationNo selection occurs (leaving more offspring than competing organisms)If all five are met, the allele and genotypic frequencies will remain the same from generation to generation.