From exactly where, I could not say, but I love bones-- especially old, weathered skulls. To me, they are like art objects even as I know some might regard them as ghoulish. My home has them in assorted places around it-- some outside and some in.
We bury all the cattle or sheep who die on the place, but if a skull shows up years later, washed out by a storm or dug up by predators (yes, it's happened), it's fair game.
These bones, aged by nature, mostly came from the valley in which I live-- but a few were found on the desert. The last one was purchased in Mexico.
And the following is a mystery-- which is why I am posting on this subject. To what animal does this skull belong? We thought maybe coyote or fox but the photos we saw online don't look right for its shape. It was found in one of our fields without the front teeth but does have a side tooth that looks like a predator.
The painter, Georgia O'Keeffe, famously painted skulls from New Mexico. I have yet to use any of mine as models, but you never know-- maybe someday.