A rule in the desert is never to put your hands or feet into places you can't see! Now you know why!
That's a Western Diamondback Rattlesnake, one of the largest and commonest around here, and we nearly trod on it!
The combination of this dramatic threat posture and vigorous tail-rattling is pretty intimidating. So its perhaps not surprising that a number of harmless snakes also rattle their tails in this way.
