species to the island continent, they carried and distributed fire.
Even for a fire planet like Earth, humans are special. For the first—and probably the only—time an organism seized control over ignition itself. That moment was unique, unprecedented, and it is unlikely that Homo will ever allow another species that experience. Thus the elaborate rituals by which human societies preserve fire have an allegorical dimension. Once acquired, humans would never allow fire to be extinguished. Fire remained as part of Homo’s biological heritage, and around it much of human culture has evolved. Take fire away from a human society and its technological base would be devastated.
The onset of domestication and the acquisition of fire were reciprocal processes: if Homo domesticated fire, it was equally true that the nurturing of fire advanced the domestication of Homo. The hearth fire became the practical and symbolic center of human society; it defined family, group, nation. The hearth expanded to become a ring of fire that shielded humans from the dangers of the night. It divided the world of the human from that of the nonhuman. As the ring moved outward, it projected human will and imprinted a human touch. Humans advanced like a flaming front, steadily expanding their protective, transforming, magical ring of fire.1
RING OF FIRE
Again and again, as conditions waxed and waned, new species of Homo incubated in Africa, then dispersed to all the contiguous lands accessible to them. The critical range was apparently the chronically disturbed rift valley of eastern Africa. Near here the other great primates flourished; here the fossil record, though always tenuous, is best preserved; here climate and biological potential carved savanna from forest on a landscape abundantly fired by lightning and volcanics. Here it appears Homo emerged as a distinct genus some 2 million years ago.
The event was long in coming. During the Miocene anthropoids had colonized the Gondwana tropics in Africa, Eurasia, and South America. The ancestral great apes, Pongidae, thrived only in Africa and Eurasia, however, appearing about 15 million years ago. Hominidae arrived probably 5–4 million years ago. The hominid alliance included Australopithecus and, perhaps 2 million years later, Homo; some specialists would accept also Ramapithecus, which is ancestral to the australopithecines, and the closest of the great apes, the chimpanzee and the gorilla. While the precise evolutionary relationships between the major members of the alliance are unclear, a reasonable guess is that the earliest hominid, Homo habilis, broke free of Australopithecus around 2 million years ago. Within a few hundred thousand years—that is, by 1.7–1.5 million years ago—it was replaced as the dominant hominid by Homo erectus. H. erectus thrived until 200,000 years ago, and perhaps as recently as 100,000 years ago, when Homo sapiens claimed supremacy.2
Among the critical differences between H. habilis and H. erectus were a dramatic growth in brain size, more sophisticated stone tools, and the acquisition of fire. With firemaking, the new hominids merged two evolutionary trends, one trend common to many genera and one specific to Homo. To the fire adaptations among Earth’s flora and fauna, hominids added others. To the human capacity to make and use tools, they contributed a new implement. Toolmaking was a necessary preadaptation to fire, for without the capacity to grasp tools, humans could not apply or remove firebrands. Likewise, the capacity to start fires by percussion or drilling, as distinct from the much older ability to preserve fire, surely derived from experiments in tool manufacture with flints, bone, and wood.
Yet fire was not mandatory to hominids. Australopithecus apparently wandered widely throughout Africa and southern Eurasia without fire, as did Homo habilis, who possessed some stone tools but lacked fire. Few flora are utterly helpless before fire; few fauna recoil in terror from flames. Domesticated dogs and livestock will lie or stand beside humans as they, too, stare into flames. The Philippine tarsier, it is reported, will gather around a quiet fire and even pick up coals (from which practice comes its scientific name, Tarsius carbonarius). Full-blown flight occurs only before rare conflagrations, a reasonable response. When early hominids used fire, they mimicked processes in nature—hunting along fire fronts as did other predators and raptors, scavenging among burned areas, slashing and burning not unlike winds and lightning. But once established, Homo’s fire practices revolutionized human society and its relationship to the natural world.
Homo erectus became a fire creature. The hearth granted heat, light, power. Cooking redefined the availability of foods, rendering edible many seeds, meats, and roots otherwise too tough, poisonous, or unpalatable to consume; anthropogenic fire began to slow cook the Earth. The reformation of diet made possible a reformation in dentition, which allowed new patterns of facial muscles and a loftier skull. A controlled flame fire-hardened wooden spears and gave flint a stony tempering. Later, fire made possible a primitive metallurgy and ceramics. Humans used fire to fell trees, to carve trunks into dugout canoes, even to mine. The hearth fire expanded the realms of climate accessible to human existence. The controlled flame was a technology of incredible, almost universal power.
The warming hearth similarly reconstituted society as it drew together bands of hominids and restructured domestic relationships. It defined a family or a group; it defined Homo. Yet it was a precarious presence, in need of constant attention. Humans knew how to capture and preserve fire long before they knew how to make it. Even when the skills and equipment were present to ignite fire almost at will, fire was preserved in slow matches or coals. The hearth fire acquired ceremonial, sacred properties, and was never to be allowed to extinguish; the role of fire keeper was among the earliest of human roles and institutions. The preservation of fire, in turn, demanded shelter, which fire often helped provide. If windbreaks shielded flames, so too could fire hollow large trees into habitable cavities, and smoke could drive off bears, sloths, and saber-toothed tigers that would otherwise compete for caves. Even without roofs and sides, fire itself made a kind of cave of light and heat. Fire’s brilliance prolonged the day, extended the realm of human activity, even apparently altered the circadian rhythms that governed sleep cycles. With fire, humans—hunted by so many nocturnal predators—could quell some of their fears of the night. Within their protective ring of fire they could work, eat, talk, and sleep.3
That fire ring segregated their cultural world from the natural environment around them. For such creatures there could be no innate fear of fire. Any member who instinctively pulled back from flame would be automatically excluded from the human group. To pass through the ring of fire—to live within it—was, in practice and symbol, the mark of humanity. Around their evening fires they told stories, related myths, danced to rites; fire induced a kind of hypnotic, contemplative reverie. Though sacred, fire remained peculiarly human—a gift (or theft) from the gods, but not often a god itself. Still, the ability of humans to use firebrands and the capacity of so many lands to receive fire expanded the ring of fire from hearth, cave, and hollowed bole outward. It remade the natural world into a humanized world.
Broadcast fire was important for hunting and habitat, for foraging and the early domestication of flora and fauna. Fire could drive game—and most birds and mammals valued as game by humans thrive in fire-prone biotas. Smoke flushed game out of nests and caves. Burned areas were prime sites for scavenging and tracking; the sour odor of charcoal even suppressed most smells, an advantage for humans whose sense of smell was crude. Burning maintained such preferred habitats as savannas and forest-grassland eco-tones. Broadcast burns temporarily swept away cover and made travel easier. With torches humans could hunt fish and wildlife at night. Burning favored many of the tubers, nut trees, forbs, and other plants useful to a diet of foragers and exposed them to harvest. By hunting large browsers and grazers, hominids upset fuel complexes, and had they not fired sites, those fodder-rich biotas would have shifted toward scrub and woodlands.
Early hominids answered a wanderlust that urged even Australopithecus as far as Java by 2 million years ago, H. habilis throughout Africa and possibly into Southeast Asia, and H. erectus from an African hearth to Europe, China, and Java along what was becoming a virtual pilgrimage route for peripatetic hominids. But this time hominids had fire, and their progress through mountains and plains resembled a flaming front, a broadening ring of fire, feeling its way into grasses, brush, bog, and forest, here flaring and there dampening, but always widening like fiery ripples