A yellow labrador retriver dog with pink nose. Credit: Wikipedia.

(Phys.org) —Humans have been deceiving themselves for thousands of years that they're smarter than the rest of the animal kingdom, despite growing evidence to the contrary, according to University of Adelaide experts in evolutionary biology.

"For millennia, all kinds of authorities – from religion to eminent scholars – have been repeating the same idea ad nauseam, that humans are exceptional by virtue that they are the smartest in the animal kingdom," says Dr Arthur Saniotis, Visiting Research Fellow with the University's School of Medical Sciences.

"However, science tells us that animals can have cognitive faculties that are superior to human beings."

He says the belief that humans have superior intelligence harks back to the Agricultural Revolution some 10,000 years ago when people began producing cereals and domesticating animals. This gained momentum with the development of organised religion, which viewed human beings as the top species in creation.

"The belief of human cognitive superiority became entrenched in human philosophy and sciences. Even Aristotle, probably the most influential of all thinkers, argued that humans were superior to other animals due to our exclusive ability to reason," Dr Saniotis says.

While animal rights began to rise in prominence during the 19th century, the drive of the Industrial Revolution forestalled any gains made in the awareness of other animals.

Professor Maciej Henneberg, a professor of anthropological and comparative anatomy from the School of Medical Sciences, says animals often possess different abilities that are misunderstood by humans.

"The fact that they may not understand us, while we do not understand them, does not mean our 'intelligences' are at different levels, they are just of different kinds. When a foreigner tries to communicate with us using an imperfect, broken, version of our language, our impression is that they are not very intelligent. But the reality is quite different," Professor Henneberg says.

"Animals offer different kinds of intelligences which have been under-rated due to humans' fixation on language and technology. These include social and kinaesthetic intelligence. Some mammals, like gibbons, can produce a large number of varied sounds – over 20 different sounds with clearly different meanings that allow these arboreal primates to communicate across tropical forest canopy. The fact that they do not build houses is irrelevant to the gibbons.

"Many quadrupeds leave complex olfactory marks in their environment, and some, like koalas, have special pectoral glands for scent marking. Humans, with their limited sense of smell, can't even gauge the complexity of messages contained in olfactory markings, which may be as rich in information as the visual world," he says.

Professor Henneberg says domestic pets also give us close insight into mental abilities of mammals and birds. "They can even communicate to us their demands and make us do things they want. The animal world is much more complex than we give it credit for," he says.