The human capacity for language has long been considered unique to our species. However, recent studies have challenged this notion by revealing that chimpanzees possess a complex communication system that rivals that of humans in terms of its combinatorial potential. Researchers from the Max Planck Institutes for Evolutionary Anthropology and Cognitive and Brain Sciences, along with colleagues from the Cognitive Neuroscience Center Marc Jeannerod and Neuroscience Research Center in Lyon, France, have recorded thousands of vocalizations from wild chimpanzees in the Taï National Park in Ivory Coast.

Their findings reveal that chimpanzees employ four distinct methods to alter meanings when combining single calls into two-call combinations. These include compositional and non-compositional combinations, analogous to the key linguistic principles in human language. The study also highlights the versatility of these combinations, which are used in a wide range of contexts beyond mere predator alerts.

One of the most significant aspects of this research is that it suggests that chimpanzees’ complex communication system may be more similar to human language than previously thought. This has implications for our understanding of the origins of language and the evolutionary history of humans. The study’s authors propose that the capacity for complex combinatorial capacities was already present in the common ancestor of humans and great apes, challenging the views of the last century that communication in great apes is fixed and linked to emotional states.

This research opens up new avenues for investigation into the evolution of language and highlights the importance of studying the communicative capabilities of our closest living relatives. As Cédric Girard-Buttoz, first author on the study, notes, “Our findings suggest a highly generative vocal communication system, unprecedented in the animal kingdom… This changes the views of the last century which considered communication in the great apes to be fixed and linked to emotional states, and therefore unable to tell us anything about the evolution of language.”

The lives of Sumatran orangutans living in zoos have been found to significantly alter how they interact with their environment, according to a recent study comparing wild and zoo-housed individuals. Researchers analyzed over 12,000 instances of daily exploratory object manipulation (EOM), revealing that orangutans in zoos engage in more frequent, diverse, and complex exploration than their wild counterparts.

“Our study shows that orangutans in zoos not only explore more but also explore differently,” said Isabelle Laumer, first author of the study. “What’s especially fascinating is that even when exploring the same kinds of objects, zoo-housed orangutans showed a richer repertoire of actions and were more likely to use tools or manipulate multiple objects at the same time.”

The study compared EOM behaviors in wild and zoo-housed orangutans across a wide age range. Data were collected from 33 wild individuals aged between six months and 76 years, as well as from 24 individuals in four zoos in Germany and Switzerland, with ages ranging from seven months to 49 years.

The results showed that zoo-housed orangutans explored objects more frequently than their wild counterparts, while there was no difference in exploration duration when individuals did explore. In contrast, wild orangutans primarily explored naturally occurring objects like plants, bark, and sticks, whereas zoo-housed orangutans engaged with a wider variety of enrichment items designed to encourage manipulation and cognitive engagement.

Importantly, the age at which orangutans first engaged in specific types of exploration was consistent across both settings, suggesting an innate developmental sequence. However, zoo orangutans continued to explore into adulthood, while wild individuals’ EOM declined sharply around weaning age (about 8 years old), likely due to the demands of survival in the wild.

In human infants, object exploration enables learning about physical properties such as texture and weight while stimulating cognitive and motor development – a pattern observed in many non-human animals as well. The heightened exploration may enhance cognitive flexibility and problem-solving skills in zoo-housed orangutans, as they interact with varied enrichment items and have more time and energy to devote to learning through exploration.

“These findings underscore how profoundly the environment influences animal behavior and cognitive development,” said Caroline Schuppli, senior author of the study. “And it also offers unique opportunities – by comparing wild and zoo-housed animals, we can better understand the full extent of a species’ cognitive potential.”

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In a groundbreaking study, wild chimpanzees have been observed eating and sharing fruit that contains alcohol. Researchers from the University of Exeter set up motion-activated cameras in Guinea-Bissau’s Cantanhez National Park to capture footage of these fascinating creatures.

For the first time, scientists have confirmed that chimps are consuming fermented African breadfruit, which contains ethanol (alcohol). This raises intriguing questions about whether and why our closest relatives deliberately seek out alcohol.

In humans, drinking alcohol leads to a release of dopamine and endorphins, resulting in feelings of happiness and relaxation. Sharing alcohol through traditions like feasting helps form and strengthen social bonds. Could wild chimpanzees be getting similar benefits from eating fermented fruits?

The researchers used cameras to film chimps sharing fermented breadfruits on 10 separate occasions. The fruit was tested for alcohol content, with the highest level found being equivalent to 0.61% ABV (Alcohol By Volume). While this is relatively low, the scientists suggest it may be just the tip of the iceberg, as 60-85% of chimps’ diet consists of fruit, which could lead to significant consumption.

The researchers emphasize that chimps are unlikely to get “drunk,” as this would clearly not improve their survival chances. However, recent discoveries about a molecular adaptation that increased ethanol metabolism in the common ancestor of African apes suggest eating fermented fruits may have ancient origins in species including humans and chimps.

Dr Kimberley Hockings from the University of Exeter notes, “Chimps don’t share food all the time, so this behavior with fermented fruit might be important. We need to find out more about whether they deliberately seek out ethanolic fruits and how they metabolize it.” If so, it suggests the human tradition of feasting may have its origins deep in our evolutionary history.

Anna Bowland’s work was funded by the Primate Society of Great Britain, providing a fascinating glimpse into the behavior and biology of our closest relatives.