Fossil records indicate that Homo erectus emerged as a distinct hominid species about 2 million years ago. H.erectus possessed an increased cranial capacity relative to other pre-humans, having brains about 75 percent as large as those of modern humans. They were also the first hominids to migrate from Africa, reaching East Asia and much of Europe. They were certainly tool makers and users, but their mastery of fire is still debated

Some believe that H.erectus was too crude to master as abstract a concept as fire creation and management. There is little evidence that they ate burnt meat, suggesting that they never used fire for cooking. Hearths are not always to be found at sites visited and used by H. erectus, unlike sites used by more modern Homo sapiens, where hearths are ubiquitous. The theory goes that H. sapiens, the first modern human species, domesticated fire along with their other great discoveries.

Fire gave great advantages to whoever first tamed it. At night, it provided protection from the predators that preyed on pre-humans. It could prove a powerful aid in hunting by improving visibility and stimulating secondary growth of edible plants favored by game. Fire provides the light necessary to use dark, damp caves as shelter. Most crucially, it provided the warmth necessary for humans to spread out of Africa. It is difficult to imaging the hairless H. erectus living in Northern Europe without knowledge of controlled fire.

The most compelling evidence that early H. erectus managed fire comes from Kenya. There, at Koobi Fora, 1.6 million year old orange patches of earth contain clues about the origins of man-made fire. As with all such finds, it is necessary to demonstrate that these fires were the result of deliberate actions by pre-humans and not the result of a natural event such as a lightning strike. Two features of the patches at Koobi Fora provide highly persuasive evidence that H.erectus controlled fire. The first is the crystalline melting of earth indicating that the fires at these sites burned at around 400 °C. The second is the composition of the plant matter used for fuel, as indicated by phytolith analysis [1].

Campfires, by design, burn much hotter than natural brushfires. This is accomplished by better air flow and more suitable fuel. Everyone knows from experience how the bark surrounding tree and bush branches burns slowly, protecting the rest of the wood. One reason we use chopped wood in most hearths is that the interior, drier wood burns faster and hotter than the outer bark. Another is that cut wood has more surface area, allowing more air to fuel a fire. Modern campfires generally burn at nearly 600 °C, while a typical brushfire burns around 100 °C [1]. Therefore, evidence that the fires at Koobi Fora burned at higher temperatures suggests they were deliberately assembled and tended by the hominids who camped there. H. erectus certainly possessed the crude axes necessary to prepare wood and kindling for such a brightly burning fire. The question is then: did they have the reasoning and forethought to do so?

The phytolith analysis may help to answer that question. Phytoliths are nearly-indestructible silica deposits found in plants. Archaeologists are able to match different phytoliths to different plant species. The phytoliths at the Koobi Fora site came from a mixture of woods and grasses, with palm tree dominating [1]. Not only does the heterogeneous nature of the plant material indicate that it was gathered by humans, the predominance of palm wood suggests forethought went into creating these fires. Palm wood is easy to light and burns brightly [1]. If H.erectus was able to select the most suitable fuel, was basic wood preparation beyond the scope of his abilities? Both require experimentation, observation, and modification.

Even if one is unswayed by the ancient sites in Africa, there are many other Old World sites that show evidence of controlled fire prior to the emergence of H.sapiens from Africa 200 thousand years ago. In Israel, on the banks of the Jordan River, archaeologists have found hearths that date to about 790 thousand years ago [2]. In Europe, sites in Britain, France, and Germany all show hearths around 400 thousand years old [1,3]. It is clear that domesticated fire was not the brainchild of anatomically modern humans, but has been part of human evolution for nearly a million years, perhaps even longer.

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