Natural Selection Unit Biology
January 29: Lesson Question How might new species form? What keeps species separate? On the top of page 80
What is a species?
Species and Speciation Let’s watch this short video on speciation. Specitaion So what is speciation?
Geographic Isolation (allopatric) A physical barrier separates a population into two (or more groups)
Speciation What keeps similar species from breeding and becoming one species?
Ecological Isolation Species occur in same region but rarely encounter each other. Eastern Blue Bird Mountain Blue Bird
Temporal Isolation Species that breed during different times of the day, different seasons or different years cannot reproduce. Western Spotted skunk (winter) Eastern Spotted skunk (summer)
Behavioral Isolation Mating behaviors are different between similar species. Birds of Paradise Blue Footed Booby
Mechanical Isolation For many insects, male and female reproductive organs of closely related species do not fit together. Damsel fly penises