In Brian Sykes's 2004 book Adam’s Curse: A Future Without Men, he described how male fertility could be decline to the point where men will no longer be able to reproduce naturally. In our recent interview with Dr. Sykes, we asked him what kinds of interventions he would endorse to save the Y chromosome.
There's a question about whether we should save the Y chromosome. There's many ways you could get around it with a sort of genetic engineering approach. I think that it’s a long time in the future, so there are other species that have lost their Y chromosome and have as a result gone extinct.
We at least know about it, so we can do something else. But I’ve always wondered whether actually it is technically feasible -- it will be soon -- for women to have children without the intervention of men at all, and I don't mean sperm donors even, but by fertilizing one egg with another. So from a sort of very long-range view that is entirely theoretical at the moment, I guess it’s possible that eventually a new human species will evolve which has no men at all and we’ll evolve from the reproduction of one woman with another.