She Has Her Mother's Laugh: The Powers, Perversions, and Potential of Heredity by Carl Zimmer Read Free Book Online Page A

to know exactly how much early farmers understood about breeding as they carried it out. The historical record of their ideas is practically a void, but the results of their efforts were impossible to ignore. The wealth of the Habsburg kings of Spain, in fact, came in part from the mysterious art of animal breeding. The first sheep to graze the meadows of Spain were unexceptional creatures with rough wool coats. When the Moors arrived, they brought sheep with them from northern Africa, which they interbred with the resident flocks. The new cross came to be called theMerino. For centuries, Spanish shepherds bred Merinos by the millions, every year leading them on a journey across the country. The Merinos spent each summer grazing in the Pyrenees and then traveled narrow paths for hundreds of miles to the southern lowlands to pass the winter. Over many generations of breeding, Merino wool became extraordinarily soft, lush, and silky.
    Merino wool turned into a precious commodity. On their journeys, Spanish shepherds would stop to shear their sheep and sell their wool at fairs to merchants from across Europe. Henry VIII of England said he would accept nothing but Merino for his royal garments. Merino wool became so valuable to Spain that smuggling a single Merino sheep out of the country was made a crime punishable by death.
    In the seventeenth century, the magnificence of Merino wool was as mysterious as the suffering of the Habsburg kings. No one at the time would have guessed they shared anything in common. Some speculated that the environment in which the Merinos lived was responsible for their wool. The cold of the mountains and the heat of the tablelands influenced their seed, in the same unknowable way the terroir of a grapevine determined the taste of its wine. More evidence for this influence came from the few cases when sheep were smuggled out of Spain. In other countries, they failed to thrive. After a few generations of crossbreeding with native flocks, the sheep no longer grew good wool.
    Across Europe, the growing population was clamoring for more wool—as well as for more beef and leather from cows, for more eggs from chickens. Wheat, barley, and corn were in greater demand as well. Anyone who could steer heredity in a more profitable direction stood to make a good living. A particularly successful breeder could even become a celebrity. And no breeder in the 1700s was more famous than a portly Englishman namedRobert Bakewell. A duchess once referred to him as “the Mr. Bakewell who invented sheep.”
    Mr. Bakewell was born in 1725 on Dishley Grange, a 450-acre property that his father worked as a tenant farmer. His father encouraged him to learn new techniques by traveling to other farms around England, Ireland, and the Netherlands. He helped his father improve the farm, digging a labyrinth of channels and hatches to deliver water across the property, tripling the amount of grass that grew on it. Robert Bakewell took over Dishley Grange by the time he was thirty. A decade later the first hint of his breeding skill emerged when he won first prize at the Ashby Horse Show.
    But it was with sheep that Bakewell would become famous. He and his neighbors reared a humdrum local breed known as Old Leicester. The animals were heavy, long, and flat-sided. They grew rough wool, and their mutton, a coarse-grained meat with little flavor, brought no excitement to the dinner table. But when Bakewell looked at an Old Leicester sheep, he saw a New Leicester sheep waiting to emerge. The generating powers inside the animals could, with the proper guidance, produce a breed that could make sideboards groan with huge cuts of delicious mutton—while requiring relatively little feed. Bakewell was a man of his mechanical age, engineering woolen meat-making machines.
    Unlike an engineer, however, Bakewell did not understand the natural processes he was trying to manipulate. He could only guess, picking out ewes from his flock that