Timeline of human history - Timeline 9: 1,750,000 BP to Present - The Age of Homo Erectus. Evolution of the Human. Fire, language, social life, complex tools

Timeline of human history
version 2 - by Finn Sivert Nielsen

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Timeline 9 - 1,750,000 BP to Present
The Age of Homo Erectus. Evolution of the Human. Fire, language, social life, complex tools

Zooming further in to the last 1.7 million years before the Present, we can now indicate roughly the climatic fluctuations contained within the 2.58-million-year-long Quaternary Ice-Age. The ragged top edge of the green field in the timeline indicates approximate temperatures during the period in question, with the high points (reaching interglacial temperatures of the kind we are used to) suggested in red. About mid-way along this edge the glacial-interglacial cycle suddenly lengthens from about 40,000 to about 100,000 years. At present we thus experience a series of 100,000-year glaciations, alternating with approximately 10,000-year interglacials. All of what we know as "human history" is contained within the later parts of the last, Holocene, interglacial. Timeline 9 draws attention to the long reign of homo erectus preceding the Holocene. During the last 2 million years many essential developments have clearly taken place, though detailed evidence or good dating may be difficult or impossible to obtain. The most obvious example is language. We will never have positive knowledge of when language originated, for the simple reason that all language at the time was spoken or signed and none of it written down. There are, roughly, two theories of how language originated. In one, the process is gradual, lasting perhaps millions of years, and proceeding step by step from simpler to more sophisticated forms. In the other theory, the preconditions for language may accumulate over time, but language itself comes as a sudden quantum leap, in which all the preconditions suddenly fit together into a functioning whole. My own view of this matter (for what it is worth) tends toward compromise. It seems natural to assume a gradual evolution of language, punctuated by more or less dramatic and sudden imaginative leaps, in which "everything comes together" - for a while. Control of fire is another elusive innovation that most likely originated at this time, perhaps in several places simultaneously, and no doubt proceeding gradually from fire "caught" in the wild to fire actually lit by humans. Finally, hunting itself - as a technique, an esthetic, a system of knowledge, and a coordinated cooperative venture - evolved gradually from what was essentially scavenging to true hunting, though most likely it too, as suggested above, went through minor quantum leaps in the course of its evolution. Homo heidelbergensis had a brain size of 1250 ccm, considerably larger than that of h. erectus, and only somewhat smaller than our own. Around 600,000 BP these brainy creatures start spreading out of Africa into Europe and Asia (where they encounter h. erectuses that arrived from Africa a million or so years before). The conditions they encounter as they venture northward are alluring, but tough. Most of the time, glaciation covers large parts of the North, though the ice recedes for brief interglacials. Outside the glaciated areas, large deforested swathes of tundra and steppe opened up, where immense flocks of grazing animals could be hunted by the new arrivals. At least two homo species evolved in direct response to these conditions: Homo (sapiens) neanderthalensis, otherwise known as the Neanderthals, evolved in Europe, the Middle East and parts of West Asia, where they are well documented. Suggestively, they have a brain size larger than our own, though the significance of this is unknown. It is also interesting to note that Neanderthals survived on Earth for more than half a million years, while homo sapiens sapiens (ourselves) have so far been around for no more than 200,000 (an absolute maximum, more reasonably 130,000) years. More recently, scientists have found skeletal remains of what is clearly another homo species, in the Altai mountains of Siberia, dubbed homo (sapiens) denisova, though little else is known about them. Homo sapiens sapiens, in contrast, evolved in Africa, and only started spreading to the rest of the world around 50-60,000 years ago. To return to the subject of sudden vs. gradual change, note the simultaneity of: i. the evolution of homo sapiens sapiens, ii. a sudden diversification of the limited, by now ancient, acheulaen repertoire of tools, iii. the near-certain achievement of modern language.