And in order to make sure their chompers are up to the task, they lose and replace about 20 teeth every day, according to a new study published in Proceedings of the Royal Society B. "For you and I, that basically looks like losing a tooth every single morning," co-author Karly Cohen, a doctoral candidate at the University of Washington, told As It Happens host Carol Off. "Like, we'd wake up and a tooth would be gone and then it would come back. It's nuts."