During all but the last 70,000 or 40,000 years of [...] two million years of tool-making, the hominid family’s potential command over the biosphere hardly began to be translated into accomplished fact. There was, of course, some technological progress during the Lower Palaeolithic Age, but in that age this progress was slow and feeble, and each of the successive technological innovations spread uniformly throughout the Oikoumenê (in the Lower Palaeolithic Age, the Oikoumenê did not yet include the Americas). The dissemination of Lower Palaeolithic technological innovations was slow; for the new type of tool had to be transmitted by pedestrians from one community to another, and, in this food-gathering stage of economy, human communities could not live close to each other, since each party required a large area to roam over in order to pick up its livelihood.
Though there was perhaps some ocean travel even by Middle Palaeolithic hominids.
Lower Palaeolithic runs from c 2.6 million years ago. Middle Palaeolithic from c 300,000. Upper from c 50,000, soon after homo sapiens had left Africa, until the invention of agriculture c 10,000 years ago.
If you distinguish only Lower and Upper, homo sapiens appears in Lower. Otherwise, he can be said to have reached anatomical modernity during Middle.
Moreover, we may guess that Lower Palaeolithic hominids, including the most successful species, homo sapiens, were conservative-minded, and that they were shy of adopting an innovation, even when they had the new pattern in their hands. The reason why, nevertheless, new types of tool spread uniformly throughout the Oikoumenê was that, though transmission was slow, innovation was infrequent. The time-intervals between successive innovations were long enough to allow each innovation to spread throughout the Oikoumenê before the next one followed.
In the history of technology the Upper Palaeolithic revolution, which broke out about 70,000/40,000 years ago, was epoch-making. From this time until the present day, improvements in tools of all kinds have accelerated, and, though there have been local and temporary pauses, and even relapses, acceleration has been the paramount tendency in the history of technology during this latest age.
But the age of relative uniformity continued until the beginning of civilisation.
During the period c. 3000 B.C.-A.D. 1500, the respective speeds of dissemination and innovation were reversed. New types of tools were invented before the previously current types had time to spread throughout the Oikoumenê. Consequently the ecumenical uniformity that was characteristic of the Lower Palaeolithic Age [and Upper] gave way, during the subsequent ages, to differentiation. New inventions did not have time to travel from their place of origin to the farthest extremities of the Oikoumenê before they were superseded regionally by further inventions.
The speed of dissemination did not overtake and surpass the speed of invention again till after the fifteenth century A.D. when the conductivity of the Oikoumenê was suddenly increased by the West-European peoples’ invention of a new type of sailing-ship which could stay at sea for months on end and could therefore reach every shore and could circumnavigate the globe.
Now uniformity has returned.
Within the last five hundred years, the speed of both the dissemination and the invention of tools has become immensely greater than it was during the first two million years of tool-making. But the Modern Age and the Lower Palaeolithic Age have one feature in common with each other. In the Modern Age [post-AD 1500] and the Lower Palaeolithic Age alike, the speed of invention has not kept pace with the speed of dissemination, and in both cases the consequence, on the technological plane, has been a high degree of ecumenical uniformity.
Mankind and Mother Earth, OUP, 1976, posthumous