Victorians Undone: Tales of the Flesh in the Age of Decorum. Kathryn Hughes

      Like any migrating countryman, William Willis brought his old skills and pastimes with him when he settled in London. Breeding pedigree dogs and fancy birds had long been a profitable sideline for urban barbers, since it required minimal space and capital. It drew too on a discerning eye and a feel for physical form. If you could tend a gentleman’s whiskers, or advise him on his bald patch, it was a short step to running your hands over a prize spaniel’s coat, or measuring the length of its tail with your eye.

      Although Darwin had himself been born a countryman – it was only eleven years since his exasperated father had yelled at him for caring about nothing except shooting and dogs – he had been away from the loamy farmlands of Shropshire for a long time. Talking to men like Willis jogged his memory about the way forward-thinking landlords, including his own Uncle Jos Wedgwood in Staffordshire, cross-bred livestock to produce juicier, taller, woollier, stronger, milkier animals, which could be mated in turn to bring about a permanent swerve in the species. Here, thought Darwin, might be a useful analogy for what happened in a state of nature, where animals that were best adapted to their surroundings survived and bred, passing on their genetic advantage to their offspring. Cooped up in the ‘vile, smoky … prison’ that was London in high summer, Darwin harvested his country friends’ expertise on selective breeding. He quizzed his old college contemporary Thomas Eyton about his owls and pigs, while William Yarrell, a Fellow of the Zoological Society, was happy to explain his experiences of crossing established breeds with hybrids.