Monkey business: artist chimps paint in their own style, study shows

"Zamba draws nothing but dots. Loi sketches curves and triangles. Misaki fills the page with large fan-shaped patterns. These aren't children in an art class. They are chimpanzees, and they each have their own style," writes ethologist Cédric Sueur on Instagram, sharing images of each chimp's distinctive art.

Sueur is one of four primatologists, three from France and one from Japan, who collaborated on a study published this month in the scientific journal Primates.

The colleagues analysed nearly 500 drawings produced by six chimpanzees at the Great Ape Research Institute, a sanctuary in southern Japan that takes in chimpanzees and bonobos that were once used as laboratory test subjects.

The team provided the animals with paper, paint and brushes. They were not trained to use them and weren't offered a reward for doing so.

By analysing 494 drawings over eight years, each piece dated and attributed, the researchers discovered that every chimpanzee has its own unique graphic signature, which evolves over time.

"Three dimensions structure the artwork of all individuals – the way they occupy space, the diversity of shapes, the richness of colours – exactly the same way as in orangutans and human children," Sueur says. 

"These styles evolve over time: the chimpanzees increasingly fill the frame, diversify their shapes and develop more complexity."

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Changing styles, colours

Researchers observed that the colourful fans that Misaki systematically drew took up more and more space on the page, for example. Their shapes became more intricate, the colours changed with the seasons and, much like in children's drawings, their style refined itself over the years.

These changes may also reflect chimps' mood and energy levels. In winter, chimpanzees go out less and see fewer bright colours around them, Sueur posits.

"Their drawings change with the seasons, being less elaborate in winter, as if their inner state were leaving its mark on the paper," he writes.

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Although the chimps' drawings were always abstract, never figurative, they seem to be influenced by what they see. One chimpanzee named Molly began painting in blue and yellow after being visited by Japanese schoolchildren wearing uniforms in those colours.

Ethologists are continuing their research to better understand what motivates animal artists such as chimpanzees, orangutans and elephants, who have been known to paint with their trunks.

This article was adapted from the original in French by RFI's Caroline Lachowsky.