Authors: Paul Whelan, Department of Environmental Studies, Western Washington University, Michael Medler*, Western Washington University, Kate Harrison, Department of Environmental Studies, Western Washington University
Topics: Biogeography, Human-Environment Geography, Africa
Keywords: Hominin, Evolution, Cooking Hypothesis, Volcanism
Session Type: Paper
Presentation File: No File Uploaded
We propose that hominin evolution may have been influenced when our ancestors began cooking food on thermal features associated with the long-term volcanism found in the African Rift. Richard Wrangham’s “cooking hypothesis” proposes that access to cooked food drove many of the evolutionary adaptations that differentiate modern humans from the other hominins found before the arrival of Homo erectus approximately two million years ago. These adaptations include, among others, reductions in the size of mouths, teeth, jaw muscles, and digestive tracts. Wrangham also argues that access to the extra nutrition available in cooked food provided the energy required for the sudden 50% expansion of the brain we see with the arrival H. erectus. However, there is little direct evidence that hominins were able to control fire at that time, or that fire was a daily agent on the landscape. We propose that during this time, many groups of hominins may have had access to thermal features, such as steam vents or hot springs. Such access could have provided a means of cooking food for evolutionarily significant populations of hominin long before they developed the cognitive abilities necessary to make or control fire. To evaluate the veracity of our hypothesis, we developed maps overlaying hominin archeological sites over the massive lava flows occurring while these steps in our evolution were occurring. These maps demonstrate that many of the hominins were living in close proximity to long term active volcanism and likely had access to thermal features that could cook food.