Americans’ love of turkey is driving producers to make the bird larger than nature intended.
The average weight of a turkey before it’s slaughtered has more than doubled since 1930, to more than 30 lbs.
Turkeys wouldn’t have gotten this large without humans. We wanted bigger birds, and science provided a way: artificial insemination. Larger turkeys can’t procreate naturally—they’re physically too large and muscled—so farmers use artificial insemination to bypass that step, while simultaneously ensuring genetic material for the largest possible turkey is being passed down.
“You can spread the one tom [male turkey] around better. It adds a whole new level of efficiency. You can spread him over more hens,” John Anderson, a breeder at Ohio State University, told The Atlantic. “It takes the lid off how big the bird can be.”
And it’s not just turkeys. Chickens have actually surpassed the Thanksgiving bird when it comes to weight gain, according to a report (pdf) from the US Department of Agriculture. Live-chicken weights have increased 40% since 1990, from an average of 4.38 lbs to an average of 6.12 lbs in 2015.