“Why did humans evolve big brains? St Hugh’s Tutorial Fellow in Human Sciences, Professor Thomas Püschel, is quoted in an article from New Scientist exploring changes in brain sizes throughout human evolution. The article mentions some recent work by Professor Püschel and colleagues, where they analysed the human fossil record to better understand the patterns that describe brain size increases over time. While many studies have explored this topic, none have specifically distinguished between changes within individual species and those between different species.
Using a new analytical approach, this study shows that the growth in brain size over approximately 7 million years primarily occurred within individual species, leading to a general increase in relative brain size across human evolution. For example, when Homo erectus first appeared in the fossil record about two million years ago, its brain volume was as little as 550 cubic centimetres. By the time the last Homo erectus were walking the Earth, some 108,000 years ago, that volume had at least doubled. This within-species increase seems to have been experienced by most, if not all, hominin species. Notably, this work also shows that the trend of increasing brain size has accelerated in more recent lineages, meaning that later species, such as Neanderthals and modern humans (that’s basically us), increased their brain sizes at a faster pace.
To read Professor Püschel’s paper in full please click here.
