According to the Pacific Northwest Region of the Forest Service (or the person responsible for the agency’s Twitter feed, anyway), a tom turkey’s wattle changes color depending on the mood he’s in. If he’s scared, it’s blue; if he’s feeling randy, it turns bright red.
Reminds me of when I was a kid. Raised as I was on Peanuts and comic books and Saturday morning cartoons, I was convinced—up until an embarrassingly late age—that the irises of my eyes turned into hearts whenever I spied an attractive girl.
Never said I was a particularly smart kid.