Speciation Flashcards
What are the 3 things that qualify for a population as a species?
ability to mate with one another, produce fertile and viable offspring, and occur in nature (naturally)
Isolation _____ lead to speciation
could
Isolated species have to be what type of isolated to go through speciation?
reproductive isolation
Reproductive Isolation
Condition in which a reproductive barrier keeps two species from interbreeding
What are the two types of reproductive barriers?
prezygotic and post-zygotic
What are the types of pre-zygotic barriers?
geography, temporal, behavior, mechanical/anatomy, genetics
What are the types of post-zygotic barriers?
hybrid sterility and hybrid non-viable
Pre-zygotic geographical
Physically separated species by geographic barriers
Pre-zygotic temporal
Timing of mating is not aligned
(ex. different breeding seasons, time of day)
Pre-zygotic behavioral
Different courtship or mating behaviors
(ex. songs, gestures)
Pre-zygotic mechanical/anatomy
Reproductive structures are physically incompatible
Pre-zygotic genetics
gametes contain different numbers of chromosomes or can not fertilize each other
(ex. diff chromosome # and diff proteins that help with fertilization)
Post-zygotic hybrid sterility
offspring are sterile
(ex. horse x donkey = mule (sterile/infertile))
Post-zygotic hybrid non-viable
offspring do not develop or are too weak to mature
Allopatric speciation
When geographic isolation leads to speciation
