What's even more impressive is that the long-term memory of a flatworm is apparently two weeks. These guys barely have a brain and are decapitated and have to regrow their heads and tiny brains and still know exactly how to find food they were taught to find two weeks previously, when we have trouble remembering where we put our car keys this morning...io9 also remarks on the passing of RIP Elaine Morgan, popularizer of the Aquatic Ape Hypothesis, a truly bizarre theory that proposed proto- humans spent time adapting to a water environment (which, she said explained a newborn's innate ability to float). The theory also threw feminism into the mix, as if it wasn't convoluted enough. But it was the 70s, which might explain it. Beyond that, we have no explanation--we can't even find our car keys, remember?