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In the U.S., it’s Thanksgiving, which means today is all about the Turkey. So here’s a fun fact you may not have heard to chew on as you masticate your meal: you can tell a turkey’s sex by it’s poop.

That’s right — male turkeys and female turkeys crap different turds. The toms’ feces are long and skinny, while the hens’ are coily little clumps.

A tale of two poos. (Credit: Figure 1 from Bailey, 1956. Reproduced with permission from the publisher.)

While it might seem strange that males and females would have such different bowel movements, it makes a lot more sense when you consider their anatomy.

The quirk of clumping results from the fact that turkeys, like many birds, expel their droppings from a multi-functional orifice also used for reproduction. Separation of the terminal ends of their genital and digestive tracts just isn’t their thing. And that a one-stop shop is called a cloaca.

In female turkeys, the droppings exit the large intestine into the cloaca. Because this little corridor is large and stretchy (remember, it fits around their eggs as well), the droppings can curl and clump before finally exiting.

Male turkeys have a rudimentary phallus in their cloacas located near the tail end of their digestive tract. That means less space for the droppings on their way out — no wiggle room for coiling.

Why don’t all birds show this kind of sex-specific poop shape? In other species, like chickens, the males’ genitalia are further reduced, so their poops are less distinctive.

Also of note: turkey droppings contain both feces and “urine” — that’s the white part (if you want to learn more about that, see this post). Because you really never can know too much about turkey turds, right?

Now you know, and you can tell your family all about the different shapes of turkey droppings while you gather around the table to feast. It’ll be slightly less nauseating than talking politics, amirite?

Happy Thanksgiving!

Citation: Bailey, R.W (1956). Sex Determination of Adult Wild Turkeys by Means of Dropping Configuration. The Journal of Wildlife Management 20(2), 220. Figure 1 reproduced with permission from Wiley.