All creatures, from the banana-buzzing fruit fly to the great blue whale, have some form of memory. Elephants remember the locations of distant watering holes. Mice remember how to find their way through laboratory mazes to food. And squirrels, who bury up to 10,000 nuts every year, remember—most of the time—where they put them. Crows remember human faces. So, beware: If you’re ever mean to a crow, they’ll likely remember you.
Of all the memories in the animal kingdom, though, yours is especially impressive.
Each human brain contains about 90 billion neurons—and each of these can form more than a thousand connections with other neurons. Memories are stored in these connections, called. This all adds up, scientists estimate, to more than 60 trillion connections, 2.5 million gigabytes (GB) of
