This weekend, I came across an animal video on Facebook that blew me away. It depicted a turtle attacking a very startled orange tabby cat.

As the cat lay on the kitchen floor of some pet owner's apartment, the turtle repeatedly hit it with its head and shell. The cat, clearly annoyed, eventually moved two feet away and flopped down on the kitchen floor again — only to be tackled by the turtle again. On and on this behavior continued. My mouth was hanging open for the entirety of the video.

Captivated, I searched YouTube for other examples of this behavior — and boy was I surprised! In video after video, I saw turtles chasing cats (and some dogs), extremely slowly, in an attempt to hit and bite them.

I tried to rationalize the behavior. Some turtles are territorial, so maybe the cat was intruding on its space? Or perhaps the turtle had mistaken the cat for a very large, furry piece of food?

Let me just say this right now: I was super wrong. As it turns out, what I mistook as territoriality is actually just typical, albeit confused, turtle mating behavior.

"They are probably (mistakenly) exhibiting courtship behavior."

"Basically, the tortoises in the videos are almost certainly males and they are probably (mistakenly) exhibiting courtship behavior with the cats and dogs," says Lucy Hawkes, a marine turtle researcher at the University of Exeter in the UK. Given how perky the turtles are, these videos were probably shot sometime in the summer, which is typical mating time for sliders and spur-thighed tortoises, the types of turtles in the videos. And the hitting and biting is just the unfortunate way males woo their dates, she says.

"The males shell-butt the females"

"When they enter courtship, the males shell-butt the females and nip them (not very romantic eh?)," Hawkes told The Verge. "Turtles are not renowned for their higher cognitive skills, so I think they are mistaking some other animal creature — in this case cats and dogs — at the approximate same height as them for a lady turtle and they are trying to get it on."

In case you're wondering, this behavior isn't restricted to land turtles. "I have heard of marine turtles mounting SCUBA divers before, so it’s across the turtle domain really," Hawkes says.