I too have been to New Mexico and through out all the South West, as a matter of fact. I've hiked in the desert. Not once did I see remains of dead indians, buckaroos, cows. Where's all the Southwest cattle drive evidence?
I saw petrified wood. But no bones or remains of any kind. I'm sure things die in the desert, I just didn't see any of that. It's a big ol' desert, the Southwest.
But like I said, there are remains of Semitic people living in Goshen for over a couple hundred years at least. The evidence is there, in the dirt.