Unit #12: Speciation Flashcards
Define the biological species concept.
Defines that a species is a group of individuals that can interbreed and produce fertile offspring.
What is a hybrid.
Offspring of two different species. Usually infertile.
Define the morphological species concept.
Defines that a species is a group of populations that share physical characteristics (size, shape, form).
Define prezygotic barriers.
A barrier that physically prevents reproduction.
Define a postzygotic barrier.
A barrier that prevents survival/development/reproduction of offspring.
What is an example of a habitat isolation barrier.
One type of chipmunk is on an island, one chipmunk is on mainland, they never interact.
What is an example of temporal isolation barrier.
Some fish of the same species lay their eggs at different times of the year.
What is an example of behavioural isolation.
Sexual selection
What is an example of mechanical isolation.
Their “parts” not being able to physically work together.
What is an example of gametic isolation.
Egg doesn’t have right receptors for sperm.
What are the different types of prezygotic barriers?
Habitat isolation, temporal isolation, behavioural isolation, gametic isolation, mechanical isolation.
What are the different types of postzygotic barriers?
Reduced hybrid viability, reduced hybrid fertility, hybrid breakdown.
What is reduced hybrid viability?
Zygote is not viable
What is reduced hybrid fertility?
Hybrid cannot breed
What is hybrid breakdown?
When offspring is much smaller than the parent, and it cannot put enough energy needed into reproduction.
