SYDNEY, Oct. 28 (UPI) -- Guppies don't appear all that bright. How much can a fish brain that small actually compute? Enough to do simple math, apparently.
New research out of Australia proves guppies can count, some better than others.
In a series of experiments, scientists at Macquarie University found guppies were able to differentiate between groups of two and three, both in real-world and artificial contexts. Some fish were able to differentiate between three and four.
Previous research suggests the ability to accurately differentiate between two number sets hits a threshold at three versus four. Animals can still differentiate between the sizes of two groups, but they use a less-precise system of ratios to estimate and compare sizes.
The latest research links the guppy's counting abilities with brain structure. Guppies with more lateralized brains -- brains which process different information in two separate portions of the brain -- were better counters.
"It's a bit like having a dual processor in a computer," Culum Brown, a biologist at Macquarie, said in a press release. "Obviously information processing is far more efficient and faster if two processors can independently analyse two different sources of information simultaneously."
"Our experiments show that fish with strongly lateralised brains could differentiate between three versus four objects, both in natural and artificial contexts, whereas those with non-lateralised brains could only differentiate two versus three," Brown said.
In a new paper, published in the journal Frontiers in Behavioral Neuroscience, Brown suggests the guppy may explain why animals began evolving increasingly lateralized brains.
Being able to accurately differentiate between two groups is advantageous when you're in the wild trying to decide which group of prey to follow or which groups of predators to avoid.
"Imagine a scenario where one pack of wolves faces another in a territorial dispute," Brown explained. "The smaller pack is much less likely to win and should back down if they are out-gunned. When faced with a predator guppies must chose the largest shoal to join because there is safety in numbers."
