Although the earliest Homo sapiens arose forty thousand years ago, humans evolved from several hominid species, the first of which emerged four million years ago in Africa (8-9). However, the leap to civilization wasn’t made until eight thousand BCE, because this leap required several advances (15). Agriculture, communication, technology, and leadership were just some of the conditions humans had to fulfill to have a culture. For scientists, anthropology is the study of how our species has been modified over epochs to fit in its ecological niche today. For historians, studying prehistory is the key to explaining our culture and what drives the actions that have comprised history ever since. But for both, this provides a door to explore the human condition we all share.
The twentieth century yielded substantial evidence that modern humans have evolved from four to one million year old ape-like ancestors in Africa (7). Although it was common belief that the first humans emerged in Asia, archaeological digs (especially those by the Leakey family and Johanson in the 1970s) have found the earliest fossils in countries such as Tanzania, Ethiopia, Chad, and Kenya (10-11). The first of these, 3.6 million year old footprints, are of an Australopithecus africanus. Since they are bipedal, they are of the Hominidae family and thought to be a direct evolutionary ancestor of the Homo genus (7). Many more fossilized species, some evolutionary dead ends and others immediate ancestors of Homo sapiens, were found, most of which were in the Homo genus (8-9). Eventually, a Cro-Magnon was discovered in Europe dating back to thirty thousand years BCE. Cro-Magnons were morphologically identical to modern humans. Although very much prehistoric, they were toolmakers, planned hunters, and even artists (cf. Lascaux Cave Paintings in France). These and other portents of civilization enabled them to outcompete their hominid ancestors and populate the world (10, 13).
Hominids and modern humans emerged and evolved because their traits were selected for reproduction by the environment; this follows the principle of natural selection. The first hominids, australopithecines, had two distinct and advantageous attributes that enabled them to survive: bipedalism and an opposable thumb. The former enabled them to, “travel distances more easily…spot threatening animals, and carry food and children” (7). The latter enabled them to grasp and make tools (7). However, tools weren’t made until a new genus and species evolved called Homo habilis. Next, the Homo erectus outcompeted the H. habilis because of its adaptability and sophistication. “Upright man” made specialized tools, migrated, controlled fire, and even had the rudiments of a language (8). Finally, the Homo sapiens appeared as Cro-Magnons, who, with their superior intellect, populated the earth (9). Each of these human species was selected for because they had a larger brain than their ancestor (8-9). Thus, the modern human is the fine-tuned product of ancient ape-like ancestors; the refinery in this case has been natural selection.
Although human civilization first appeared ten thousand years ago, the seeds were planted much before this time. Two achievements we accredit to the hunter-gathering Cro-Magnons of the Paleolithic Age are language and leadership (24). The former was already developing with Homo erectus, but Cro-Magnons used it more comprehensively (8, 10). This form of communication was essential to having humans work together in a civilization. The latter occurred in small familial hunting groups, where the patriarch would guide the rest to game and safety. A leader was necessary to maintain order within the kinship group, which would eventually lead to a civilization (14). However, one invention that was pivotal in the development of culture occurred during the Neolithic Age: agriculture. When, “some of the women may have scattered seeds near a regular campsite,” and came back later to see crops growing, the agricultural revolution sprung to life (15). Along with this came the skill of taming animals (16). Growing crops and domesticating animals provided a steadier source of food in comparison to hunting. The results of this were twofold: first, clans could now settle down in one place (cf. Jarmo and Catal Huyuk), and second, certain members could adopt less survival-focused jobs. With these conditions met, the roots of a culture could finally branch out (15-18).
As discoveries in the past century have demonstrated, from australopithecines to Cro-Magnon men, while the Hominidae genus has evolved over forty million years, civilization and culture has existed for less than ten millennia. However, humanity’s tale has not finished. New transitions in the fossil record are still to be found which will provide a more detailed portrait of our evolutionary ancestors. For example, just in 2002, a six million year old skull—the oldest human ancestor yet—was discovered in Chad (11). Moreover, the Homo sapiens species is not the end of the hominid phylogenetic tree. We are merely a stepping-stone to a much greater species—one that the environment will select from within us to populate the earth one day.