Frans De Waal: “How do you give a chimp—or an elephant or an octopus or a horse—an IQ test? It may sound like the setup to a joke, but it is actually one of the thorniest questions facing science today. Over the past decade, researchers on animal cognition have come up with some ingenious solutions to the testing problem. Their findings have started to upend a view of humankind’s unique place in the universe that dates back at least to ancient Greece…A growing body of evidence shows, however, that we have grossly underestimated both the scope and the scale of animal intelligence…Experiments with animals have long been handicapped by our anthropocentric attitude: We often test them in ways that work fine with humans but not so well with other species. Scientists are now finally meeting animals on their own terms instead of treating them like furry (or feathery) humans, and this shift is fundamentally reshaping our understanding.”