Scientists know some of the broad strokes for how life emerged from primordial Earth, but digging into the processes that allowed for the emergence of an oxygenated atmosphere, processes like ...

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 ...

Much more difficult is learning to connect different types of stimuli or events, and predicting that one is linked to another. Such associative learning was most famously demonstrated when Ivan Pavlov ...