The earliest instances of deliberate use of fire in the archaeological record appear increasingly across a huge geographic region from around 400,000 years ago. Researchers have suggested that this represents the earliest clear example of widespread cultural diffusion.
The ability to control fire was perhaps the most important technological innovation within human evolution. Fire provided a source of protection against cold climates and predators, extended the length of the day, and allowed humans to manipulate materials and consume a wider range of foods.
According to a paper recently published in PNAS, researchers from the University of Leiden and the Eindhoven University of Technology have shed new light on how early humans may have learnt to control fire.
The team gathered examples of early signs of fire use from archaeological sites across the world for examination.
They identified that the regular use of fire occurred at a geologically similar time (around 400,000 years ago) across major regions of the Old World – spanning Eurasia to Africa.
For example, they compared traces of charred bones recovered from layers at the Aroeira cave site in Portugal dated to c. 400,000 BC, and remains of heated lithics from Jebel Irhoud in Morocco dated to c. 300,000 BC.
Based upon this pattern, they propose that knowledge of fire was transmitted across vast regions within a short period of time due to cultural diffusion – the process of passing on practices and ideas through social learning – as the fire signals appear too rapidly to be explained by independent invention.
For different hominin groups to have passed on information about creating fires, as well as the location of raw materials, it suggests they must have encountered one another frequently, and have been tolerant enough to have socialised. Genetic evidence of interbreeding between Late Pleistocene humans supports this.
The paper also draws upon the Levallois technique as a parallel. This method of stone knapping developed rapidly around 300,000 years ago and was used by different hominin species over the same regions of the Old World.
‘To date, it was always thought that cultural diffusion actually started only 70,000 years ago when modern humans started to disperse. But the record for the use of fire now seems to show that this happened much earlier,’ said Katharine MacDonald, one of the study’s authors.
‘There will no doubt be people who don’t agree with us,’ said Eva van Veen, whose thesis inspired the study. Nonetheless, she hopes future research looks ‘more at what the use of fire meant for human development and how that related to social change’.