test1 Flashcards
What is phylogeny?
Common ancestry of an organism.
Illustrations of phylogeny?
Phylogenetic trees.
T/F phylogenetic trees are a hypothesis
True
Branch points
Divergence from a common ancestor.
Sister taxons
Organisms that share an immediate common ancestor.
Basal taxons
Group that diverged from common ancestors first.
Polytomy
More than 2 sharing a relating recent ancestors.
What do phylogenetic trees tell us?
Evolutionary relationships, patterns of decent (not phenotype, unless stated), tell us common ancestry– not who evolved from who.
Creating a tree uses both what?
Morphological and molecular data.
Definition of parsimony
kiss = keep it simple/ simple explanation.
What are the steps to creating a tree?
- observe morphological features of organisms (qualitative)
- determine # of sim/diff between organisms (qualitative)
- Start the tree, start w/ least amount of differences: sister taxons.
Morphological species concept
Individuals who look alike = same species
Ecological species concept
Individuals who share same habitat + share resources = same species.
Phylogenetic species concept
Individuals who share a common ancestor are the same species.
What 2 types of reproductive isolation are there?
Pre-zygotic and post zygotic