Several decades ago there was a problem with overpopulation
on an African game preserve - too many elephants. Limited by the technology
available at the time, the solution arrived at was to move the babies to new preserves.
Everyone watched, gravely concerned, but the babies thrived.

However, unintended consequences emerged. At the new locations, a decade
or so after the transfer, someone was killing off rhinoceros which are an endangered species.
It turned out the killers were young male elephants. At first the game wardens
couldn't believe it, this was uncharacteristic behavior never before seen in elephants.

They deduced that the young males had grown up without fathers - without
male role models. New technology had made it possible to transport into these
locations some large mature bull elephants. There was concern that it would be too late, that
the adolescent males had to have grown up with their elders, that
bringing "daddies" in now would do no good. But they tried it anyway.

It worked like a charm. The mature bulls arrived and set things
straight. The young males immediately stopped their precocious, rampant sexuality,
killing and violence.