For most of the 17 years she worked at the Aztec Animal Shelter, Kellie Willits says she used to make a habit of assuring every person who surrendered a stray or unwanted animal at the facility ...

This was an essential precaution, as weaning would not take place until the child was two years or older, and the Aztec had no animals whose milk could be used as a substitute. During those four ...

This is believed to be one of the most abundant cases of mass animal sacrifice ever found in Teotihuacán and comparable only to those conducted by the Aztec empire more than 1,000 years later.

They are comparable to the animal sacrifices conducted by the Aztec empire a millennium later. The Aztecs conducted ritual sacrifices often, offering 400 different animal species to their gods.