Karl Popper, the philosopher of science, quite clearly supports the concept of a priori knowledge. Not knowledge as in knowing the laws of gravitation, but knowledge as in knowing about and how to deal with gravitation.
In the essay "The Epistemological Position of Evolutionary Epistemolgy" in the essay collection All Life is Problem Solving, Popper suggests that life must know something about the universe in order to survive through even the first few minutes of its existence.
For the adaptation of life to its environment is a kind of knowledge. Without this minimal knowledge, life cannot survive.The observable fact that life exists tells us that this knowledge, which Popper calls "genetically a priori," also exists.