BIOL 2400 Chapter Notes - Chapter 9.3: Molecular Evolution, Hiv, Restriction Enzyme
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Phylogenetic trees are actually hypotheses about the relationships among species or groups of individuals the relationships are constantly being tested as more and more evidence and new methods become available. Maximum parsimony a statistical method for reconstructing phylogenies which identities the tree topology that minimizes the total amount of change, or the number of steps, required to fit the data to the tree. Purifying selection (negative selection) removes deleterious alleles from a population. It is a common form of stabilizing selection. Bootstrapping a statistical method for estimating the strength of evidence that a particular node in a phylogeny exists. Distance-matrix methods methods that construct phylogenetic trees by clustering taxa based on the proximity (or distance) between their dna or protein sequences. These methods place closely related sequences under the same interior node, and they estimate branch lengths from the observed distances between sequences. Neighbor joining a distance method for reconstructing phylogenies.