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1. macro-evolution: evolution above the species level
2. micro-evolution: evolution below the species level
3. speciation: occurs when one species splits into two, which involves a reproduc-
tive isolating mechanism
4. example of reproductive isolation but NOT speciation: leopard frogs in Florida
vs. Maine, can still reproduce but just can't because they are isolated; gene flow can
happen
5. extrinsic isolating mechanism: factors producing geographic isolation which
physically separates individuals (ex: movement of tectonic plates; mountains)
6. Intrinsic/ Pre-zygotic: no a physical barrier separation; this isolating mechanism
prevents sperm from meeting egg; prevents zygote from ever forming
7. example of pre-zygotic isolating mechanism: different pine tree species pro-
duce pollen at different times of the year
8. post-zygotic: a zygote forms but might have a mutation that will cause it to die
after
9. examples of post-zygotic isolating mechansim: infant can be born but is sick
and dies; the resultant offspring is sterile!
10. fundamental principle of natural selection: rate of evolutionary change is
directly proportional to the degree of variability in the population
11. corollary natural selection principle: fate of all evolutionary lineages is extinc-
tion; 99.9% of all lineages ever existing on Earth went extinct
12. anagenesis: change in a species over a long period of time; supports gradual-
ism theory of evolutionary change
13. cladogenesis: sudden split results in formation of 2 species from 1 species;
supports punctuated theory of evolutionary change
14. phyletic gradualsim: emphasizes anagenesis; slow change over time that
leads to formation of a new species
15. punctuated equilibrium: emphasizes cladogenesis; evolutionary change from
sudden speciation events
16. adaptive radiation: rapid expansion & diversification of a group of organisms as
they adapt to a newly available ecological space; involves rapid speciation/cladoge-
nesis; occurs from new changes that open up potential new habitats to a group of
organisms
17. what type of theory of evolutionary change does a phylogenetic tree
