Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
lecture 10
| Term | Definition |
|---|---|
| phylogeny | evolutionary of the lineage or lineages (populations, genes, or species) |
| phylogenetic tree | visual representation of a phylogeny |
| phylogeny is similar to | family tree |
| nodes | represent common ancestors for all descendent lineages |
| clades | common ancestor and all of its descendants |
| taxa | can be rotated around nodes and still depict the same relationships |
| tip | the terminal end of an evolutionary tree, representing species, molecules, or populations being compared |
| phylogenies depict | taxa in nexted hierarchies |
| taxonomic units are accurate if they | represent clades (monophyletic groups) |
| some linnaean taxa are | not monophyletic, such as the fishes |
| fish are | paraphyletic (4 monophyletic clades) |
| characters | are identifiable heritable traits (insect wings) |
| characters states | condition of the character (present or absent) (not primitive and advanced) |
| synapomorphy | derived character state shared by an ancestor and its descendants |
| outgroup | used to infer approximate ancestral character states |
| reconstruction of phylogenies is based on | analysis of character states |
| not all traits are | similar due to synapomorphies |
| homoplasy | character state similar not due to common descent |
| convergent evolution | independent evolution of similar traits in separate lineages (streamlined body form of dolphins and fish) |
| evolutionary reversal | reversion back to an ancestral character state (can happen thru mutations) |
| principle of parsimony | simplest scenario requiring the fewest evolutionary steps is usually preferred |
| polytomy | we cant determine which members of these branches are the most closely related |
| incorporating related fossils in a phylogeny adds | constraints to divergence times |
| fins and limbs are | homology thru time |
| coelacanths are | one of the closest living relatives of tetrapods |
| phylogenies can be used to | generate hypotheses about major transitions |
| coelacanth fins are | homologous with tettrapod forelimbs |
| tiktaalik | transitional fossils between fish and tetrapods (wrists and neck) |
| tiktaalik forelimbs share more | homologies with tetrapods than Eusthenopteron |
| eusthenopteron | bones that were homologous to the long bones of our arms |
| acanthostega | had all this plus 8 digits at the ends of its limbs |
| phylogeny revelas how | tetrapods traits evolved over time |
| mammalian ear bones are | homologous to bones of the reptilian jaw |
| phylogenies allow us to trace the | transition of bones from jaw to ear |
| zhenyuanlong | vaned feathers arranged in layers on their forelimbs |
| exaptation (also known as preadaptation) | describe a shift in the function of a trait during evolution, common in anatomy and behavior |
| feathers evolved from other functions such as | species recognition |
| exaptation | natural selection co-opts a trait for a new function |
| heterochrony | evolutionary change in form due to change in rate or timing of developmental events |
| a change in growth rate of parts can | produce a new final stage |
| paedomorphosis | a change of timing produces a sexually mature adult w/ juvenile feature |
Created by:
jcava141
Popular Ecology sets