Abstract
Recent research argues that an association with fire, stretching back millions of years, played a central role in human evolution resulting in many modern human adaptations. Others argue that hominin evolution was driven by the roughness of topographic features that resulted from tectonic activity in the African Rift valley. I combine these hypotheses to propose that, for millions of years, active lava flows in the African Rift provided consistent but isolated sources of fire, providing very specific adaptive pressures and opportunities to small isolated groups of hominins. This allowed these groups of early hominins to develop many fire specific adaptations such as bipedalism, smaller teeth and mouths, shorter intestines, larger brains, and perhaps a host of social adaptations. By about 1.8 million years ago, Homo erectus emerged as a fire adapted species and mastered the technology necessary to make fire itself. This technology allowed them to move into the rest of the world, taking a new kind of fire with them that would change ecosystems everywhere they went. This hypothesis is supported by recent geologic work that describes a large lava flow occurring in the region of the Olduvai Gorge during the 200 000 year time period we believe Homo erectus emerged in the area.
Highlights
This paper evolved from a talk I gave in Savanna, Georgia, at the opening plenary of the 4th International Fire Ecology and Management Congress in 2009
I proposed that lava flows in the African Rift, occurring over millions of years, provided consistent and isolated sources of fire, perhaps creating specific adaptive pressures and opportunities for small isolated groups of hominins, and possibly leading to a set of adaptations that contributed to the evolution of modern humans
I propose that we consider the additional possibility that, like the other systems and species we study, humans are highly fire adapted
Summary
In his book Catching Fire: How Cooking Made Us Human, Wrangham (2009) argues strongly that many of the physical traits that separate species in the genus Homo from other species are the results of several million years of interaction with fire He argues that our consumption of cooked foods provided more efficient digestion, leading to shorter intestines, smaller mouths, smaller teeth, and freeing caloric resources to support increased brain sizes. Burton (2009) argues that, for perhaps as long as six million years, hominins’ relationship with fire led to exposure to nighttime light, producing changes in circadian rhythms and diurnal activity patterns, which in turn led to hormonal changes and many physical and social adaptations, ranging from bipedalism to language Both of these books offer compelling arguments and extensive literature citations for anyone interested in diving deeply into this emerging hypothesis of human evolution.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
