This led to " reproductive isolation " which is the hallmark for the concept of biological species, he said.
32.
That is, they still carry a significant part of their unique genetic inheritance, developed over millenniums of reproductive isolation.
33.
This indicates that the mechanisms of reproductive isolation can arise even though the interspecific hybrids are not selected against.
34.
In particular, Dobzhansky described the critical role, for the formation of new species, of the evolution of reproductive isolation.
35.
A key innovation may result in reproductive isolation, whereby those individuals with the innovation no longer breed with those without.
36.
Recently, molecular techniques including the combined use of backcrosses indicating limited fitness for hybrids and effective reproductive isolation and speciation.
37.
In many species where pre-copulatory reproductive isolation does not exist, hybrids are produced but they are of only one sex.
38.
Hochberg et al . suggest that parapatric speciation can result from reproductive isolation caused by social selection : individuals interacting altruistically.
39.
Usually complete reproductive isolation does not occur until many generations, but behavioral or morphological differences separate the species from reproducing generally.
40.
Basically all the forms of speciation have to do with some type of ( perhaps functional, not physical ) reproductive isolation.
