Evolutionary Patterns Flashcards
What are the ways evolutionary patterns can be studied?
By looking at:
- Origination patterns (originate in bursts or constantly?)
- Extinction patters (grouped at certain times or constant?)
- Taxonomic duration (how long species exist for)
- Rates of evolution
- Fossils and biogeographic patterns
How can cladograms be used to study evolutionary patterns?
By replacing the name of species with the location they were found. It can show the migration of a group over time.
What are the three types of extinction?
- Background extinction (standard rate of extinction)
- Pulses of extinction (extinction events)
- Mass extinctions
What are the big five mass extinctions?
- End Ordovician (short glaciation)
- End Devonian (pulses due to aquatic anoxia)
- End Permian (atmosphere pollution and heating)
- End Triassic (atmosphere pollution and heating)
- KT (bolide impact)
What is the Red Queen hypothesis?
Evolutionary arms race, things must be constantly evolving. Due to competition.
What is the Court Jester hypothesis?
Environment drives evolution
What is the interaction between the Red Queen and Court Jester hypotheses?
They are not mutually exclusive (can occur simultaneously)
What is the Signor-Lipps Effect?
The fossil record of an organism will never be complete. (First and last organism will never be recorded)
What is the difference between phyletic gradualism and punctuated equilibrium?
Phyletic gradualism: species gradually evolve
Punctuated equilibrium: there are quick evolutionary changes from species to species
PE is what actually happens.
Why are mass extinctions hard to study?
Long stratigraphic sections are needed in a variety of habitats
What does species sorting mean for evolution?
Fledgling (new) species are more likely to survive if they are ecologically different to parent species. (Have a different ecological niche).
What does species selection mean for evolution?
Differential rates of speciation and extinction. (e.g. ammonites speciate quicker than other species)
What does habitat tracking mean for evolution?
Ecological communities follow habitats as they move during environmental change.
Shifting locations to preferred habitats.
What defines a bird?
- Feathers
- Carpometacarpus (remodified arm)
- Unique foot structure (for perching)
- Pygostyle (tail)
- Hollow bones with pneumatic foramen
- Sternum and keel (supports flapping muscles)
- Furcula (wishbone, attaches sternum and keel)
- High EQ, advanced vision
What was an archaeopteryx?
A feathers dinosaur with flight feathers and a furcula.
