what is reproductive isolation? what is its significant

Hello Student
Reproductive Isolation is when an ancestral species give rise to new species and these species are not able to breed or mate between each other due to geographical barrier or environmental barrier.
For example Mule is a species produce from the mating of a male donkey and female horse.
And this is the significance of this,as these are not able to breed or mate because these are not able to produce sperms.

Hello Student,
Reproductive isolation comprises behavioural or physiological processes that prevent interbreeding of animals of two different species. These processes help in maintaining integrity of species and prevents transfer of gene flow between species.