The Maya civilization had one of the most intricate religious systems in the ancient world. From powerful gods like the maize god and the rain god Chaac to the complex calendar cycles and ancestor ...

Priests recorded their rituals in hieroglyphic books ... gods and human sacrifice were even more important. The Maya believed the Earth had the form of a giant turtle that floated on an endless ...

It was within the caves that the Maya performed their rituals and sacrifices. Today, it's possible to visit these caves when you explore the jungles of Quintana Roo and Yucatan near Cancun.

But while "only male children were selected for sacrifice" here, rituals varied. Ancient DNA degrades faster in tropical areas, but "we're getting better and better at retrieving even very small ...