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
Sympatric speciation
When any method other than geographic isolation is the reason speciation occurs
What is similar between allopatric and sympatric speciation?
both use reproductive isolation factors
