Darwin on Inbreeding


Darwin‟s start in life was not promising. He showed no interest in following his father‟s profession of medicine and no aptitude for any of the professions open to a gentleman. His
father wrote to him in despair. “You care for nothing but dogs, shooting and rat catching. You will bring nothing but shame and disgrace upon yourself and your family.”

Even so he sent his son to Cambridge, from where Darwin emerged three years later with a degree. Ignoring his father‟s disapproval, Darwin immediately signed on the sailing ship Beagle as a
collator of fossils, flora and fauna, a study for which he was eminently suited. Five years later he returned with his findings, though it was to be another twenty years before
he published his controversial book “The Origin of the Species.” It was an immediate best seller, but Darwin was almost submerged by the tide of fury and scorn that descended on him,
mainly from the religious section. They had always taught that God made the world in seven days and all his creatures were immediately perfect and immutable, which Darwin rejected;
Darwin‟s reply was “I cannot prove my theories but I believe that one day enlightened scientists will do that for me.”


To date no one has ever been able to prove Darwin wrong. His interest in inbreeding was fuelled by the loss of four of his beloved children at a young
age. His wife, who was very religious, put this down to „An Act of God.‟ Darwin, who was not, attributed it to the fact that he was the third generation of his family to marry their
cousin. Amongst his other interests Darwin was a great pigeon fancier and marveled at the diverse breeds that had all descended from the same forbear the humble rock dove. He also owned extensive greenhouses in which he conducted countless experiments on plant inbreeding. In the end he reached two firm conclusions. 1. All close inbreeding leads to a loss of vigour and fertility.
2. Continuous close inbreeding leads to extinction. Thirty years ago when Professor Yates of Bristol University was shown a Collie pedigree, in
which every male and most of the females went back to Dazzler, he said “You will pay for this.” His words have always haunted me. Fortunately modern pedigrees show more
diversity, but we would do well to keep Darwin‟s findings in mind. Recently there have been quite a number of importations of collies from abroad, most of them
of excellent quality, not everyone is in favour but at least it will enlarge the gene pool, and that can only be a good thing.