June 18, 2009

Some Fish “˜Learn’ Like Humans

Scientists have discovered that sticklebacks exhibit an advanced, sophisticated learning technique never before seen in the animal world. 

The research reveals that the learning methods of fish may resemble that of humans more than previously believed.

The study, conducted by researchers at St. Andrews University and Durham University in Britain, found that nine-spined sticklebacks can observe others to make better decisions. This ability to select the best food patch by comparing how successful others are has not been seen in animals before.

The scientists studied 270 nine-spined stickleback fish, and discovered a majority of them were capable of comparing the behavior of other sticklebacks with their own experience and select which fish to emulate to find more food.

The researchers speculated the fish might be capable of something known as the "hill-climbing" strategy, something humans have but has not yet been discovered in other animals.

"Nine-spined sticklebacks may be the geniuses of the fish world," said Professor Kevin Laland from the school of biology at St. Andrews University, the study's co-author.

"It's remarkable that a form of learning found to be optimal in humans is exactly what these fish do," he told BBC News.

The researchers put the fish in an aquarium, and gave them worms from feeders at each end of the tank. The fish initially preferred the feeder with more worms.   The scientists then fed the fish more worms from the feeder at the other end of the tank, while the first group of fish was allowed to observe before feeding themselves.

The scientists found that nearly three-out-of-four of the observing fish were able to determine that the feeder which initially gave them fewer worms was now dispensing more, and went for that second feeder.

Interestingly, if the fish observed feeders providing roughly the same amount of food they did not emulate the other fish and instead kept with their own selection.

The researchers said the findings add to the understanding of brain evolution and the types of brain required for some types of cognitive functions.

"Lots of animals observe more experienced peers and that way gain foraging skills, develop food preferences, and learn how to evade predators," said Dr. Jeremy Kendal, the study's lead author, with Durham University's anthropology department.

"But it is not always a recipe for success to simply copy someone."

"Animals are often better off being selective about when and who they copy," he told BBC News.

"These fish are obviously not at all closely related to humans, yet they have this human ability to only copy when the pay off is better than their own.

The research was published in the journal Behavioral Ecology.


On the Net: