This is a video of a little tortoise chasing a plastic ball across his home's hardwood floors. Come on -- install some carpet, man, you'll get better traction. Also the title of the video is 'Tortoise thinks it's a dog', which I'm fairly certain is inaccurate because there's no way that tortoise thinks it's a dog just because it's chasing a ball, I'm pretty sure it thinks the ball is another tortoise and wants to bang it. Remember: the simplest answer is often the right one, especially if it has to do with trying to bang things.
Keep going for the video. SPOILER: He abandons the ball under a cabinet and starts chasing the camera at the end.
Thanks to Luc, who wants to see that tortoise chase a hamster in a hamster ball.