Journal ArticleIn a 1945 monograph, Hrdlička argued that, at 1,000 BP, Paleo-Aleut people on Umnak Island were replaced by Neo-Aleut groups moving west along the island chain. His argument was based on cranial measurements of skeletal remains from Chaluka Midden and mummified remains from Kagamil and Ship Rock burial caves. By the 1980s, researchers had concluded that the transition demonstrated by Hrdlička, from a high oblong to a low-vaulted wide face, was merely one example of a global trend in cranial morphology and therefore population replacement had not occurred
