Dogs sometimes rely more on their memory than sense of smell when trying to find a hidden treat, according to researchers who analysed data contributed by 500 citizen scientists from around the world.
Five hundred dog owners played the same games at home that researchers use in the laboratory, and contributed data to a study to help find out about a dog's cognitive skills and problem-solving.
On five of the seven tests analysed, citizen science data corresponded closely to what had been produced by labs.
For example, in one of the game-like tests, dogs were found to rely more on their memory than their sense of smell to find a hidden treat.
The dogs watched as their owner hid food under one of two cups. Then while the dog's vision was obscured, the owner switched the food to the other cup.
If dogs could smell the food, they should have been able to choose the correct cup, but owners found that most dogs went to where they last saw the food.
The data were collected through a website called Dognition.Com that was developed by Brian Hare, an associate professor of evolutionary anthropology at Duke University.
According to Evan MacLean, a senior research scientist at Duke University, the memory-over-smell result has been replicated in seven different research groups and more than a dozen different studies.
"Most people think dogs use their sense of smell for everything. But actually dogs use a whole range of senses when solving problems," said MacLean.
Analysis of the unusually large dataset created by Dognition has also found that all dogs have a unique set of cognitive skills that they use to navigate the world around them.
Some dogs were found to be good communicators, some had better memories and others were better at taking their owner's perspective.
"Most people think of intelligence as glass that is more or less full," Hare said.
"But intelligence is more like ice cream. Everybody has different flavours. Being good at one thing doesn't mean you will be good at everything else," Hare said.
The study was published in the journal PLOS ONE.
