Did cannibalism kill Anasazi civilization?

It is one of the great prehistoric puzzles: What caused the Anasazi people, who had one of the most sophisticated civilizations in North America, to abandon their beautiful stone dwellings in the mid-12th century? What made families walk away, seemingly in great haste, leaving behind food cooking over fires and sandals hanging on pegs?

In Chaco Canyon, a stark landscape in northwest New Mexico presided over by brooding red mesas, clues lie buried within a nest of hundreds of rooms strewn among the remnants of distinctive Cibola pottery and exquisite jewelry.

Bones. Chopped-up human bones with marks indicating systematic cutting and scraping, suggesting that groups of people were killed and butchered, the meat carefully cut away at the tendons and roasted. Long bones halved and boiled to extract the marrow. Skulls, their tops removed like lids, placed on hearths and cooked. Brains removed.

Scientists have long puzzled over the meaning of these artifacts. Now, at least one chilling explanation has come forth from physical anthropologist Christy Turner. With the publication this spring of "Man Corn: Cannibalism and Violence in the Prehistoric American Southwest," which he wrote with his late wife, anthropologist Jacqueline Turner, he has managed to anger Native Americans, rile scientists, horrify New Agers and provide a fascinating theoretical glimpse into the collapse of a great civilization.