Cave divers in Mexico’s Yucatan Peninsula area may have discovered the earliest evidence of humans in the Americas. Exploration of these flooded caves is in it’s early stages since the openings are hidden deep within the dense jungle. The geology of this area is primarily limestone that is easily dissolved with rainwater. Approximately 12,000 years ago, at the end of the Pleistocene epoch the melting of the ice caps caused a dramatic rise in global sea levels, which flooded low lying coastal landscapes and cave systems. At the Aktun-Hu cave system in the state of Quintana Roo, divers reached the furthest extent of that… the pit. The pit is approximately 200 feet deep and 120 feet in diameter and the bottom of it holds the mystery. They first came across several megafauna remains and what was clearly a mastodon bone, and a human skull resting upside down with other nearby remains at about 140 feet. The skull looks pre-Maya, which could make it one of the oldest set of human remains in the area. Gaining an understanding of how this human and these animals entered the site will reveal an immense amount of knowledge from that time. Dating of the skull is still being processed but it has potential to change history in the Americas.