How Innovation Works: And Why It Flourishes in Freedom

by Matt Ridley

Mark Thomas and his colleagues at University College London wrote a paper in 2009 arguing that innovation in the Upper Paleolithic is all about demography. Dense populations inevitably spur human technological change, because they create the conditions in which people can specialize. The most striking evidence for this idea comes from Tasmania and concerns, not innovation, but ‘disinnovation’. The Tasmanian people became isolated 10,000 years ago when rising sea levels at the end of the ice age cut the island off from mainland Australia. They remained effectively uncontacted until Western explorers arrived. During these millennia of isolation, the population of the island was small – about 4,000 people – and not only showed little sign of technological innovation, but actually gave up some of the technologies that were there at the start. By the end, Tasmanians had no bone tools, no cold-weather clothing, no hafted tools, no nets, no barbed spears, fishing spears, spear throwers or boomerangs. In a key paper published in 2004, the anthropologist Joe Henrich explained this by reference to the sudden reduction in the ‘effective population size’ upon isolation. The Tasmanians went from being a small part of a huge population to the whole of a small population. That meant they could no longer draw upon the ideas and discoveries of many people. Given the need to learn skills, the technology shrank to what could be supported by limited specialization within a small population.