Dig site in Gilbert, AZ reveals more treasure

I find it fascinating to contemplate how vast the temperature changes occurred in this region to make it a place suitable for giant tortoises and mammoths.

Extreme global warming, long before factories, automobiles and CFCs.

What transforms a lush, cool region into a desert wasteland? How much do we really know about how deserts are formed and sustained? Could it be as simple as an intense solar radiation event killing almost all living things in the region at once?

And when one sees Mars, is it as easy to imagine that beneath the surface of that wasteland, a similar story awaits to be uncovered?

Food for thought. Giant tortoises aren't known for their speed. Vegetation, food and water had to be plentiful here at one time.