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
What 5 types of prezygotic (prevent fertilization) are there?
- habitat/geographical isolation
- temporal isolation
- behavioral isolation
- mechanical isolation
- gametic isolation
Biological species concept
Individuals that freely interbreed + produce viable, fertile offspring = the same species.
What does post-zygotic mean?
Hybrid of the offspring, nonviable or non fertile.
What are the limitations of the biological species concept?
Fossils, asexual reproduction, and relies on reproductive isolation.
Sympatric speciation
“Same homeland”, happened in same geographical location.
Allopatric speciation
“Different homeland” happened due to separation of geographical location.
