Profitable Wonders James Le Fanu
There was nothing inevitable about the ascent of man. Indeed, despite the theoretical advantages of the upright stance and (relatively) large brain, our earliest ancestors were almost pathetically ill-adapted for survival: defenceless against the powerful muscles and razor-sharp teeth and claws of hungry lions; unable (unlike their primate cousins) to make a speedy escape to the safety of the forest canopy; poorly insulated, due to their hairless state, against the extremes of heat and cold; and burdened with the obligation to care for their dependent offspring.
The crucial event in improving their chances in the struggle for existence was, as all know, the mastery of fire – the earliest evidence for which, approximately 1.5 million years ago, was unearthed in the 1970s by archaeologist Charles Brain in the Sterkfontein cave in South Africa. His excavations of the oldest deposits accumulated on the floor of the cave revealed the remnants of the gnawed bones of early hominids, indicating they were the prey of local carnivores. But in successive strata above he found the burned bones of wildebeest and antelope together with primitive stone tools. ‘ Homo erectus had not only evicted the predators’, he writes in his popular account The
Hunters and the Hunted, ‘but had taken up residence in the very chambers where his predecessors had been eaten.’
This mastery of fire was as much a mental as a technical achievement, requiring considerable foresight to accumulate stocks of combustible wood and the manual dexterity to generate the heat necessary to light it – whether by friction (the fire drill) or striking sparks off flints. It radically shifted the natural balance of power in Man’s favour – as exemplified by the Aboriginal practice of ‘firestick farming’. ‘They procure a great abundance of game by setting fire to the undergrowth with a kind of torch made of leaves’, recalled one observer in 1831. ‘The concealed hunters position themselves in the paths most frequented by the animals and with facility spear them as they pass by.’
As well as providing for the immediate necessities of food, warmth and protection, fire’s role as a catalyst would be more significant still by allowing humans to transform the material world around them to their immense advantage. Here cooking is the most obvious example, rendering edible the otherwise inedible: tough tubers left to soften in the embers overnight, meat tenderised and preserved by smoke.
The art of handling fire would prove essential too to the early practice of agriculture, transforming scrub and forest into fertile arable land by the practice of ‘slash and burn’: first killing trees by cutting off their branches and then, several months later, setting them ablaze. The first crops to be cultivated on a large scale, wheat and barley, were fire-dependent in a rather different way. The combination of their high nutritional value and storability for long periods made them an ideal staple food for the town dwellers of the Fertile Crescent – but they required the heat of the baking oven to be digestible.
The next, and largest, stride in the use of fire came soon after with the invention of metallurgy. Smelting malachite in charcoal furnaces at temperatures in excess of 1,000C released the red metal copper that, alloyed with tin, produced a harder metal to be moulded, drawn, hammered and cast and then fashioned into that limitless range of beautiful tools, weapons, ornaments and vessels characteristic of the Bronze Age. By the first century AD there was, notes Johan Goudsblom in his book Fire and
Civilisation, scarcely a craft or skill practised in Ancient Rome that did not rely on fire – legions of smiths and bakers, potters and glass-makers, brewers and coopers, wood-workers and ship-builders
The ascent of man is thus essentially a human construct inextricably linked to his ability to manipulate fire. But man certainly can’t take the entire credit for fire itself, which is predicated on a whole series of fortuitous phenomena stretching back hundreds of millions of years. Both the necessary raw materials of wood and oxygen are the product of photosynthesis, the chlorophyll in the leaves of trees transforming carbon dioxide and water into the sugars and cellulose necessary for their growth while simultaneously releasing oxygen back into the atmosphere. Combustion too is a unique chemical reaction, providing heat and energy while its low reactivity allows for the safe and controlled use of fire. Further, the heat generated by the hearth, it turns out, was ‘just right’ to warm our ancestors without scalding them. And the much higher temperatures from burning charcoal are ‘just right’ for smelting those metal ores. And those attributes of humans, their size and strength, dexterity and intellectual capabilities, are similarly ‘just right’ to manipulate fire – accounting for why the ability to do so lies so far beyond the competence of any other creature.