In 1897 Russian physiologist Ivan Pavlov proved that animals can be trained using associative learning—now, the same might be ...

Animals, from worms and sponges to jellyfish and whales, contain anywhere from a few thousand to tens of trillions of nearly genetically identical cells. Depending on the organism, these cells arrange ...

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Here’s what you’ll learn when you read this story: When biologists refer to ‘complex life,’ they almost ...

A recent study has found that a specific single-celled organism has the capacity for Pavlovian associative learning without a brain or even a neuron.

A growing body of peer-reviewed research is building the case that single-celled organisms, creatures with no brain, no ...