Chapter 4 Flashcards
traits:
anatomical features, developmental process, behavioral pattern
phylogenetic systematics:
Classify org. to their evolutionary histories
What’s the dif. bet. pedigrees and phylogenies
Pedigrees tells the ancestry of indiv. while phylogenies tells the ancestry of a population
taxon (plural taxa):
Group of related organisms
outgroup:
taxon related to group of interest, but it happened earlier in the evo. history
poytomy
node with more than 2 branches arising from it. This is how uncertainty is communicated
monophyletic group
taxonomic group with all descendants of group’s most common ancestory
clade
always consist of a group that shares a single common ancestor
polyphyletic group
dif members that don’t have the same common ancestor
paraphyletic group
common ancestor but not all the descendants are included
unrooted trees
do not indicate direction of time, branch tips represent more recent species than interior nodes
cladograms
trees that do not have branch length (114)
phylograms
trees that represent evolutionary change with branch lengths
chronograms
branch length rep. actual time, common in paleontology
homologus
trait that’s inherited by ancestor
analogous traits
traits shared but not from common ancestor
divergent evo
when closely related populations diverge cuz of natural selection
convergent evo
2+ populations are simi to each other cuz thye’re exposed to simi. selective conditions
synapomorphy
shared derived trait.
How it is applied: use syn. to reconstruct evo trees. The more traits 2 species have in common, the more closely related they will be
homoplasy
analogous trait
symplesiomorphy
shared trait in group that’s not shared by the 2 most closely related groups
poloarity
order of appearance in evo time
vestigal traits
class of homologous traits. Traits that have no known currenct func, but seems to have been important in the past
