It would take a lot of bending the laws of plausibility to say that this imprint isn't a human hand. It has four defined fingers and a thumb, and resembles a hand in every single way. Despite that, scientists insist that it can't be.
The imprint, which can be found on the Canadian side of the arctic, is approximately 110 million years old. Humans evolved approximately 2.8 million years ago. Who did this hand belong to, then? An alien visitor? A human time traveler?