The young, blonde Brit had come all the way to Tanzania, notebook and pen in hand, with no concept that she would change the way we understood and studied animal behaviour and cognition; specifically, how we viewed intelligence and sentience in the chimpanzee, our closest living relative. Jane Goodall’s first ground-breaking discovery came in 1960, the same year she arrived in Tanzania to begin her research. While out in the forest one day, she saw a chimpanzee whom she called David Greybeard poking pieces of grass into a termite mound to fish out the insects and eat them. This was the first documented example of genuine tool use in a species other than Homo sapiens. Until then, tool use had been considered a defining characteristic of humankind.
Jane’s findings were published three years later by the National Geographic Society in an article titled ‘My life among wild chimpanzees’, which was accompanied by romantic photos of her in the forest surrounded by chimpanzees. For many of us, the connection Jane shared with them was plain to see. A famous photograph shows her stooping down and extending her right arm to a chimpanzee baby that is mirroring her posture, its fingertips stretched out to touch her hand.
Her research exposed a ‘human’ side of another animal species, one that begged us to reconsider our understanding of animal sentience and intelligence. The scientific community, though, found her discoveries difficult to swallow. Everyone, especially anthropologists, struggled to understand what this knowledge would mean for our species’ identity. When Louis Leakey, Jane’s mentor, received her telegram describing her landmark observation he stated, ‘Now we must redefine “tool”, redefine “man”, or accept chimpanzees as humans.’ Among the many questions triggered by her research, one stood out: if chimpanzees have more complex internal and social lives than previously thought, what about other animals? The floodgate was open.
Schools of fish and sharks circle in shallow, turquoise waters.
If chimpanzees have more complex internal and social lives than previously thought, what about other animals?
A pod of spinner dolphins (Stenella longirostris) swims in the open ocean.
Because the marine world has received less attention than its terrestrial counterpart, it's not widely known that the ocean also harbours intelligent beings.
A decade later, an enthusiastic marine biologist began his scientific career studying bottlenose dolphins off the coast of Hawaii. Louis Herman endeavoured to gain insight into the dolphins’ mental faculties by studying how they communicate. So complex did this field prove to be that he dedicated the next 46 years of his career, and life, to it. What he discovered would also change the course of behavioural and cognitive science. Louis and his colleagues documented dolphins’ abilities to learn and respond to human language transmitted through auditory and visual signals. Not only did they teach two dozen words of an artificial language to a pair of dolphins, but they also realised that the dolphins could understand what individual words meant and how their arrangement affected the meaning of a sentence.
Unlike many animals, which take time to learn what human gestures mean, dolphins were immediately able to understand a signal such as pointing. This hadn’t been observed in other species and it showed, crucially, that dolphins are able to understand a species other than their own. Also unknown until Louis’ research was that dolphins use echolocation to image their environment and detect the distance, shape and size of objects. His pioneering work and discoveries proved that dolphins have complex communication and comprehension skills, which is why they are now considered the cognitive cousins of chimpanzees.
Jane Goodall and Louis Herman helped shape the animal cognition field and ignite scientific interest in the subject. It became clear that, at least for mammals, animal sentience and intelligence are complex and mysterious. Future scientists would branch out to explore the inner lives of countless other animals: elephants, dogs, pigs, ravens, whales, fishes, octopuses and sharks and rays, among others. Yet historically the marine world has received less attention than its terrestrial counterpart. For that reason, it’s not widely known that the ocean also harbours intelligent beings.
Only in the past few decades have scientists begun to peel back the layers of ocean intelligence. The discoveries have been both surprising and enlightening. What has this research told us about the intelligence of marine organisms? And how does it affect the ways in which we view our own intelligence?