麻豆传媒

WATCHING a group of 5-year-olds chasing each other in a park it is easy to forget that child鈥檚 play is a serious business. Through play children figure out how to interact socially, practice problem-solving and learn to innovate, skills that will be indispensable to them as adults. But if experiences gained during play are so crucial for cognitive development, what would it mean if a species had a shorter childhood?

This is exactly the case for our closest relatives, the Neanderthals. Behaviourally they were very similar to us, with some important differences which, to paraphrase Sigmund Freud, may stem from their childhoods.

Neanderthals evolved in Europe some 250,000 years ago, spread to the Middle East and eventually went extinct about 30,000 years ago. Much like their human counterparts they made complex tools and hunted large game animals. But they also ate fish, tortoise, hare and a variety of plants, adapting their diets to local conditions. They had language, created fire, at least occasionally showed compassion for others in their group and sometimes buried their dead. The single greatest difference between Neanderthals and humans that we can see in the archaeological record, however, lies in both the quantity and nature of the artefacts they imbued with an obvious symbolic dimension.

Humans today live in what we call a symbolic culture. All the objects around us have a symbolic dimension. The clothes we wear, for instance, send out signals about us that are unrelated to their practical function. We form symbolic relationships where no biological relationship exists, with a husband, sister-in-law, godchild, blood-brother, for example. Language, of course, is another key example, the relationship between the words and the objects and concepts to which they refer is completely arbitrary and that is the essence of a symbol.

Neanderthals created few symbolic artefacts. Before about 50,000 years ago there is very little evidence of any that stand up to scientific scrutiny. A few Neanderthal sites dating from 50,000 to 30,000 years ago contain some beads, pigments, raptor talons and indirect evidence for .

Burst of creativity

But these artefacts pale next to the record of symbolic material culture created by early humans who first evolved in Africa 200,000 years ago. Even if we focus on just the period 50,000 to 30,000 years ago we find that early humans created bone flutes, the in France, imaginative personal ornaments such as ivory beads carved to look like shells, and figurines incised with geometric patterns. Two examples that stand out for me are the region of Germany (currently on display at exhibition at the British Museum, London) and the painting of a bison-woman from Chauvet, both fantastical, imaginary creatures.

The ability to reproduce a three-dimensional form on a two-dimensional surface, or to 鈥渟ee鈥� a figure in ivory, requires a completely different way of imagining the world. Neanderthals created nothing like these artefacts and I believe this can be explained by the games they played, or more correctly did not play, as children.

. As a result, they had a shorter childhood than us. We know this because Neanderthals occasionally buried their dead so we have a relatively large collection of Neanderthal infants and children from which to measure their development. One study in particular was a game changer. In 2010, Tanya Smith from Harvard University and colleagues studied Neanderthal and early human teeth, counting daily growth lines to calculate the exact age. By comparing this to the individual鈥檚 patterns of growth, Smith concluded that .

Why should this make a difference to the minds of Neanderthals compared to modern humans? To understand this, we need to take a closer look at childhood. In general, species like us, with longer dependency periods, tend to play more and engage in many more types of play. This influences our minds, because play is an important part of the healthy cognitive development of many animals, not just humans, and being deprived of opportunities to play can be detrimental. For example, a demonstrated that those raised normally but without access to playmates suffered from the same kinds of problems as rats with damage to their prefrontal cortex, a region of the brain involved in social behaviour, abstract thinking and reasoning. In other words, play shapes the brain. But the kind of brain we have also shapes the type of play we engage in.

Humans are unique in that we engage in fantasy play, part of a package of symbol-based cognitive abilities that includes self-awareness, language and theory of mind. Its benefits include creativity, behavioural plasticity, imagination and the ability to plan. Being able to imagine novel solutions to problems and to work out their consequences before implementing them would have been an enormous advantage for our early human ancestors 鈥� this is exactly what we are practising when we play 鈥渨hat if鈥� games. From what we can tell, it is unlikely that Neanderthals were able to engage in fantasy play, and it is this level of imagination that underlies the differences in material culture between Neanderthals and early humans.

We need to add one final piece to the puzzle: the Neanderthal brain. Neanderthals experienced accelerated brain growth compared to us, according to from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who concluded that this meant the environment has less impact on the connectivity of their developing brains. Taking a modern example, accelerated brain growth in children with autism lessens their ability to read social cues and engage in fantasy play. The same may have been true for Neanderthals. This leads us to believe that their perception of the world, and their level of engagement with it, was different from ours.

鈥淣eanderthals鈥� level of engagement with the world was different from ours鈥�

I think that it is only through years of 鈥渢raining鈥� their unique brains through fantasy play in childhood that modern humans were able to create fantastical symbolical artworks like the Chauvet bison-woman. The shorter Neanderthal childhood, combined with their lack of complex fantasy play, influenced the adults they became, and the artefacts they left behind.

This article appeared in print under the headline 鈥淎ll work and no play left little time for art鈥�