- justin gregg
- special for BBC
Dolphins – sociable, playful and communicative – are widely considered the second most intelligent animals after humans.
But in recent years interest in the cognitive capacity of dogs has risen and researchers from specialized centers say that many more things happen in the brain of dogs than previously thought.
In some cognitive tests, they actually outperform great apes and dolphins.
So what does science say? Can dogs be intellectual rivals of dolphins?
«There is a lot of evidence that dogs have a better ability than primates to interpret a person’s communicative intentions,» says Laurie R. Santos, a psychologist at Yale University, USA, who studies primates and canines to understand better human mind
«They understand that people try to communicate information and they use those communicative signals better than primates.»
This ability of dogs makes them one of the few animals that understand what humans mean when they point to something.
Even chimpanzees don’t look further than a fingertip when a person points to a plate of food.
A dog can use the finger signal and gaze direction as clues to locate objects.
This talent is very rare in the animal kingdom, although dolphins have it too.
But there is one cognitive feat in which dogs outperform almost all animals.
According to American advisers who train Chaser, a Border Collie dog, she can understand more than 1,000 words used to name her toys.
When asked to bring a Bamboozle, an orange horse, Chaser easily distinguishes it among various other objects.
Kanzi the bonobo, a famous language-altered ape, has a vocabulary of less than half the words of Chaser’s.
And the prodigious dolphins at the Kewalo Marine Base Mammal Laboratory could only manage 40 words.
Dogs win, it seems, if it comes to learning the meaning of individual symbols.
More than 1,000 words
Unlike dogs, dolphins seem to be good at solving problems.
In an experiment, they were asked to find a series of weights scattered in a pool to put on a box to get a reward (food).
Almost immediately, the animals had the idea of picking up all the weights at once instead of placing them one by one on the box.
This suggests that the dolphins plan their behavior and reflect on possible solutions.
Furthermore, dolphins are among the few animals that understand that they are seeing themselves when they are in front of a mirror (others are chimpanzees, elephants and magpies).
Researchers have used the mirror self-recognition test to see if animals understand that they exist as separate entities in the world, with their own thoughts and minds.
This level of self-awareness opens the door to greater flexibility when faced with new problems or when trying to find out what is going on in the minds of other animals.
Dogs, for their part, don’t «pass» on this particular intelligence test.
a matter of intelligence
At first glance, dolphins’ problem-solving abilities and self-awareness may seem like evidence to support those who assume that these charming mammals are more intelligent than dogs.
However, relying on hunches to assess intelligence can be problematic.
For starters, the concept of human intelligence as an ill-defined mix of various cognitive abilities, and efforts to assess it, such as IQ or IQ tests, are controversial.
Is someone good at solving algebraic equations smarter than someone who can quickly determine the motivations of others?
Is being able to remember data a sign of intelligence? And is it more or less important than logical reasoning?
Even if there were a universally accepted and human definition of intelligence, why would it have to be consistently applied to other animals?
Dogs have been bred to live in a human-generated environment: they are particularly adept at reading human social cues.
The talents with which they excel – understanding when pointed at or identifying objects – are largely the result of humans having spent thousands of years educating them to understand concepts important to us.
We have molded them according to our definition of intelligence.
On the other hand, dolphins have developed their cognitive abilities in a world unaltered by humans.
Even so, they seem intelligent to us because their complex social behavior reminds us of ourselves.
Dolphins are perhaps the most human-like non-primate animals, and that is precisely why we consider them intelligent.
But a dolphin’s brain has evolved to produce behavior that helps it deal with dolphin problems.
That includes the ability to find fish buried in the sand with echolocation or sleep with only one half of your brain at a time so you can come up to the surface to breathe.
another way of thinking
The way a dolphin thinks is a direct result of its physical, social and ecological needs, just like dogs.
Since each species has different needs, each has a unique way of thinking.
An example of why intelligence is such a problematic term is how different species perform on tests of object permanence.
This is the ability to understand that things exist even when they are out of sight, something that humans achieve at the age of 2 and is not a problem for great apes.
In one version of the test, the animal is shown a ball, for example, which is then placed in a box and covered with a blanket.
If the animal understands object permanence, it should realize that the ball is under the blanket.
However, neither dogs nor dolphins made it. Does that mean they are less intelligent?
It could, instead, indicate that they think differently.
smell and echolocation
Dogs live in a world of scents, and their understanding of objects partly involves chemical trails that will linger for hours or days.
Perhaps, then, things that are not present to the eye still have a chemical presence for them.
This can make it hard to understand what the researchers are asking.
Dolphins, for their part, have an extra sense that can make the concept of object permanence tricky.
They are able to see through some materials by penetrating them with sound waves. So a fish hiding in the sand may be invisible to the naked eye, but detectable to an echolocating dolphin. Therefore, perhaps the objects will never disappear for the dolphins.
In short, it makes as much sense to wonder which animal is smarter than it does to wonder if a hammer is a better tool than a screwdriver.
The answer depends on the task they have to perform.