Ancient 'alien-like' skulls have been found on every continent but Antarctica. Anthropologists are starting to figure out why.

An illustration of a skull missing the jawbone, with two ropes tied around its conical-shaped forehead, with rocks on both the front and rear of the skull to help shape it. .

When the Spanish first reached the Andes, they found something surprising: Many of the locals had long, pointy heads. They discovered that the Collagua, an indigenous group in Peru that was conquered by the Inca, had a practice of shaping the head starting in infancy, before the skull bones fused and soft spots disappeared.

The Spanish jumped to the worst conclusions.