Theme 1 - Phylogenies and Primate Evolution

selective agent

factor in environment that favors certain traits, causes natural selection (ex. arsenic pollution)

branch point

point on phylogeny where multiple species diverge from common ancestor

phylogenetic tree

type of phylogeny, shows relations between taxa like family tree

-hypothesis about past common ancestors

-rooted includes one common ancestor, unrooted does not

phylogeny

diagram showing how different groups of species are related, common ancestors

taxon

group of species compared in phylogenies

taxonomy

study of classifying organisms

analogy

analogous structure; similar appearance but different evolutionary history

cladistics

system that sorts organisms based on common ancestor into groups (clades)

maximum parsimony

organisms developed new traits in the simplest way (least number of branch points)

molecular systematics

using molecular data to classify species

monophyletic group

a clade (group of organisms that share common ancestor)

shared ancestral trait

shared derived trait

anthropoid

group of primates including monkeys, apes, and humans

hominin

primates that stood on two legs and evolved into humans, found in Africa

primates

Order of mammals that climb trees, have flat nails, perceive depth, and have larger brains (lemurs, tarsiers, monkeys, apes, humans)
-divided into prosimians and anthopoids