America’s lust for gigantic breasts leads to impotence: the population genetics of captive-reared turkeys

Gobble? image from http://www.public-domain-image.com

Gobble? image from http://www.public-domain-image.com

The noble turkey, a centerpiece of the American Thanksgiving supper. It looms large from its prominent position on the dining room table. The master of ceremonies – or, in my case, the guy who keeps slicing himself open with various sharp objects yet is inexplicably the one people call on when there’s knife-work needs doing – draws a set of fine, honed knives, set aside for this particular task, and carves, delicately yet firmly, into the hefty white meat of the turkey’s breast. Sure, some favor the dark, rich meat around the legs, but this white meat, soaked in gravy and topped with cranberry sauce or stuffing, that is what we crave.

“We give thanks,” the benediction may begin, “to Charles Darwin, for determining the underlying mechanism by which a theropod may, over the course of 65 million years, through a process of gradual change by means of the retention of beneficial traits through successive generations, evolve into this delicious, delicious bird.” And then, perhaps, that surly teenager, the one determined to point out the social inequalities inherent in the holiday and the colonialist attitudes which led to the wholesale extermination of America’s native peoples – every family has at least one – will chime in to quip “you know, evolution didn’t shape the turkey. The modern Thanksgiving turkey is the product of an extensive selective breeding program that began in the 1940’s. Commercial turkeys can’t even reproduce naturally, they have to be artificially inseminated.” At which point the older members of your family may blush and/or faint at such an unseemly turn of phrase.

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