Scientifically, turtles are said to stack in order to be closer to the sun for warmth, since ideal basking spots may be scarce. Also, it might be a defense against predators, to make themselves look larger. This turtle duo looks like a two headed monster, and of course two heads are better than one.
Perhaps more intriguing is an anecdote at the start of Stephen Hawking’s book, A Brief History of Time. He describes a scientist talking about modern astronomy. At the end of the lecture a woman insisted he was wrong, and that the world is supported on the back of a tortoise. When the scientist asked her what the tortoise was standing on, she replied “It’s turtles all the way down.”
Hawking went on to say that if the turtles are symbolic, this idea might not be absurd. In the views of modern physics, there is either one turtle at the bottom that stands on nothing, or it is actually turtles all the way down. Though largely discarded as an archaic Hindu myth, it makes me wonder what I might have seen if the water hadn’t been so murky. Perhaps the turtles were just the tip of an unseen pile going straight from a pond in Costa Rica to the center of the universe!