AP Biology / Unit 7: Natural Selection
7.10 Speciation
Notes
A biological species is a group that can interbreed and produce fertile offspring.
- Allopatric speciation: geographic separation. Sympatric: no separation (polyploidy, behavior).
- Prezygotic barriers: habitat, timing, behavior, mechanics, gametes. Postzygotic: hybrid inviability or sterility.
Practice
A canyon splits a squirrel population, and they become separate species. This is:
Physical separation.
Two frog species mate in different seasons. This barrier is:
Timing.
A mule is sterile. This is a:
Hybrid sterility.
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