They could be just from being in to dry or hot of an enviornment. Probably won't get much worse if the guitar is kept in an area with at least 40% humidity. I am sure there will be more opinions coming.
those are very cosmetic in nature, and should not significantly affect the guitar in anyway except looks. the top headstock layer is a veneer. so your cracks are in the finish and veneer if that deep. mainly considered weather checking like worknot said