The Broad Breasted White breed of turkeys is the most common commercially-raised turkey in the US.  But there's a problem: 
These birds have shorter breast bones, exceedingly large breasts, are often very fat, and have shorter legs than "standard" turkeys, rendering them unable to breed without human assistance (typically via in vitro fertilisation).
Unless you intentionally buy a heritage breed for three times the price, this is the turkey you eat at Thanksgiving.  (via Freakonomics)

Slightly related:  Corn sex, grape sex #nature