Are animals as smart, or as dumb, as we think they are?

Does my dog only think of eating, sleeping and chasing squirrels? Does my girlfriend’s cat really have the capacity to plot my accidental death? Are cows just walking hamburgers and pigeons intent on world domination?

Measuring animal intelligence is extremely complex, yet some animals may
be smarter than we think [Credit: Rader of Gin]

Opinions vary on the answers to these questions. But where do we get our opinions on animal intelligence?

Our understanding of, and feelings for and against different species seem to be linked to our cultural and personal prejudices. We have compassion for those closely related to us. Mammals are viewed smarter than birds and reptiles, while we think of less related species, like insects, as non-thinking machines.

The reality is intelligence is a complex concept, difficult to define and hard not to base around our own abilities.

Measuring intelligence is even more difficult. With humans we can converse or give them a written test. But the lack of language and opposable thumbs makes it extra tricky to measure intelligence in animals.

So how are researchers changing their approach to measuring animal intelligence? Today, animal cognition scientists avoid viewing humans as the apex of intellect and look at animals not as dumb furry humans, but as intelligent species that view the world in fundamentally different ways.

Tool-use is a form of intelligence long thought to be exclusive to humans. Examined in many species, only few have succeeded. When elephants were first tested, experimenters gave them a stick and placed food just out of reach. In this setup, elephants failed. Elephants knew where the food was placed and could grab the stick, but would not use it to obtain the food.

Later, researchers realised a species bias in the experimental design. Grabbing the stick with its trunk inhibited the elephant's ability to smell and feel; senses that elephants rely on much more than vision. So researchers tried something different. They added a box to the experiment. The result? Elephants kicked the box until able to stand on it to reach the food.

Deep in thought. Chimps have a better short term memory
than humans [Credit: Dmitri Fedortchenko]

In a recent study monkeys learnt that two different types of tokens would exchange for food: one type would gain food for them only while the other token type provided food for both monkeys. This set-up proved successful. Monkeys preferred tokens that rewarded both individuals.

These are two simple examples among many where animals seemed void of a certain type of intelligence. But in reality they only failed solving a task the way we expected a human would. Negative findings tell us only so much. By designing a test for the specific species in mind, researchers were able to reveal the animals' true cognitive capacities.

As tough as it is to define intelligence and to measure animals' cognitive capacities, research has provided ample evidence that animals across many different species have complex intelligence.

Squirrels fake hiding seeds when they know others are watching. Crows can construct hooks out of wire to use as tools. Chimpanzees have better short-term memories than humans.

Bumblebees can solve some problems faster than computers. Rats feel empathy for their species companions. Honey bees can recognise faces. Magpies are self-aware.

And Caenorhabditis elegans, a worm with only 302 brain cells, can learn and remember.

For some, hearing that animals are intelligent is enthralling. But for many, losing their exclusivity on intelligence is discomforting.

Several studies have shown that we rate animals' intelligence much lower if and when we eat them, a form of denial that may help us feel less guilty.