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Archeology and Anthropology

Human ancestors not to blame for ancient mammal extinctions in Africa

New research finds grassland expansion drove the decline of giant mammals over the last 4.6 million years

New research disputes a long-held view that our earliest tool-bearing ancestors contributed to the demise of large mammals in Africa over the last several million years. Instead, the researchers argue that long-term environmental change drove the extinctions, mainly in the form of grassland expansion likely caused by falling atmospheric carbon dioxide (CO2) levels.

Navajo Rug

Like her mother before her, 84 year-old weaver Salina Begay, creates Navajo rugs the old fashioned way. With help from her daughter, Begay raises her own sheep, cards, spins and dyes the wool, then weaves the yarn into traditional Navajo patterns.

Hopi Pottery

Modern ethnographic jar made by the late Joy Navasie (Frog Woman), a Hopi-Tewa potter. 

Catalog number is ET578

Donated by Dr. Allan Nelson, MD, Chicago, Illinois in 2013


Glenna Nielsen-Grimm

In 2008, Glenna Nielsen-Grimm joined the staff as the anthropology collections manager and is responsible for the care of over 900,000 objects that date as early as 10,300 BP and represent North America, South America, Mesoamerica, Pacific Islands, Middle East, Great Basin and Northern Colorado Plateau.