As Tuesday’s photo illustrated, horses can do things that look very strange—even frightening—to their two-legged owners.
The horse in the photo was yawning, but some owners will never see it happen. That’s because most horses very seldom yawn. The first time you see the behavior, you might mistake it for a seizure of some kind. The horse’s eyes roll back, his ears flop, and he opens his mouth wide enough to let his tongue hang out. The first time I saw a horse do that I was poised to run to the house and scream at my husband to “call the veterinarian!” Luckily the horse closed his mouth, chewed a little, and wandered off.
Gunsmoke exhibiting a flehmen response.
Backyard Horsekeeping 