Reproductive isolation occurs when barriers prevent two populations from interbreeding – keeping their gene pools separate
There are two main categories of reproductive isolation barriers:
Prezygotic isolation – occurs before fertilisation can occur (no offspring are produced)
Postzygotic isolation – occurs after fertilisation (offspring are either not viable or infertile)
Prezygotic isolation barriers can be temporal, behavioural, geographic / ecological or mechanical; whereas postzygotic isolation barriers include the inviability, infertility or breakdown of hybrid organisms
Reproductive Isolation Mechanisms
reproductive isolation
Temporal Isolation
Temporal isolation occurs when two populations differ in their periods of activity or reproductive cycles
Example: Leopard frogs and wood frogs reach sexual maturity at different times in the spring and hence cannot interbreed
Behavioural Isolation
Behavioural isolation occurs when two populations exhibit different specific courtship patterns
Example: Certain populations of crickets may be morphologically identical but only respond to specific mating songs
Geographic Isolation
Geographic isolation occurs when two populations occupy different habitats or separate niches within a common region
Example: Lions and tigers occupy different habitats and do not interbreed (usually)
i hope this helps
Answer:
False
Explanation:
Buoyant forces act on objects that are submerged in fluids. This includes gases and liquids.
Directional selection is where one phenotype is favored, so an example would be "a population of madagascar hissing cockroaches suffers heavy predation from lizards. Because their heads are small, the lizards are unable to eat the very largest adult cockroaches, and instead prey upon small and medium sized adults, so as a result the large cockroaches are favored and live".
Meanwhile, disruptive selection is where both extreme phenotypes are favored, an example would be "a population of rabbits can have black fur, white fur or grey fur. This population of rabbits lives in an area of white rocks. When a local volcano erupts, black volcanic rock now dots the landscape amongst the white rocks. Now the black and white rabbits live longer because the black and white spots on the landscape camoflauge them. The two extreme phenotypes are being favored."
