Reproductive Barriers

Reproductive barriers are physical processes that prevent 2 different species coming together to mate and produce offspring. Reproductive barriers have been classified into 2 separate ways either prezygotic barriers which are the barriers that the 2 different species face before, or if they even can reproduce and produce offspring postzygotic barriers are the barriers that the 2 species face after they produced offspring that usually is sterile. There are many different types of prezygotic barriers but the main ones include habitat, temporal, behavioral, mechanical, and gametic isolation.

Habitat Isolation is when the 2 different species that are similar live in 2 different habitats such as one may live in water and one may live on land. There is a possibility for reproduction but it is highly unlikely.

Temporal Isolation is when the 2 different species live in 2 different temporal areas meaning 2 different climates. Grizzly bears are found in warmer areas and polar bears are found in extremely cold areas that barely get any sun, they are both bears but live in different temporal zones of the world.

Behavioral isolation is when 2 similar species act completely different from each other and the other species doesn’t know how to react to it. Wood and leopard frogs are an example of behavioral isolation because they are both frogs but the wood frog has a mating call that only attracts the opposite sex from the wood frogs and the leopard frog has a mating call that only attracts the opposite sex of the leopard frog.

Mechanical isolation is when the 2 different species are extremely similar but their reproductive tracts don’t match up. An example of that would be snails because the bulkiness of their shells and different locations for their genitals make it a challenge for them to reproduce, also another challenge is that snails are hermaphrodites.

Gametic Isolation is when the 2 species are not able to reproduce because the sperm and egg are not compatible so there is no way of offspring being able to be produced, an example would be some sea creatures one species being a red color and only reproduce with the same color because the red colored sperm doesn’t match up with a purple sea creatures eggs.

 

Postzygotic barriers are when 2 different species are able to reproduce but their offspring is not able to reproduce making it sterile, a good example of that would be a donkey and horse coming together to make a mule but in the end the mule is sterile making it not be able to reproduce with any other species or even its own.