1. Speciation Pt 2
There are different kinds of isolation that can lead to speciation; some are prezygotic and some are postzygotic.
mechanical isolation: this occurs when mating pairs genitalia are not compatible with one another
ex: plants
reduced hybrid fertility: hybrid offspring can survive, but are unable to produce more offspring
ex: ligers and tions, mules
habitat isolation: mating pairs become geographically isolated from one another through migration or from physical barriers, do not reproduce, and over time end up being incapable of reproducing with one another
ex: Galápagos finches, fish populations

2. Speciation Pt 2
temporal isolation: mating seasons occur at different times during the day, month, or year and this means that reproduction does not occur
ex: toads and plants
reduced hybrid viability: hybrid offspring do not live very long and subsequently do not reproduce
ex: plants
gametic isolation: reproductive cells between a mating pair are incompatible with each other
ex: chimpanzee and humans

3. Speciation Pt 2
behavioral isolation: mating rituals/behaviors differ between mating pairs and mating pairs do not reproduce together as they do not recognize mating signs
ex: birds
hybrid breakdown: happening more often with plants, hybrids are viable, but as generations continue to reproduce, the hybrids become sterile

4. Prezygotic or Postzygotic?
Consider the different types of isolation below. Indicate whether they are prezygotic or postzygotic and why.
1. mechanical isolation
2. reduced hybrid fertility
3. habitat isolation
4. temporal isolation
5. reduced hybrid viability
6. gametic isolation
7. behavioral isolation
8. hybrid breakdown
1. pre-
2. post-
3. pre-
4. pre-
5. post-
6. pre-
7. pre-
8. post-