Your lily-white bed linen may, in fact, be less hygienic than the nest of an animal known for throwing its own poo around. According to a new study by researchers from North Carolina State University, chimpanzees have cleaner sleeping arrangements than humans – and that may be precisely because we insist on using the same sheets over and over. More than a third of the bacteria found in human beds is from our own bodies, be it skin, oral or faecal. PhD student Megan Thoemmes, the lead author of the paper, which was published in the journal Royal Society Open Science, said she and her colleagues “wanted to know how this compares with some of our closest evolutionary relatives”. Chimpanzees build fresh beds from branches and leaves every day. Thoemmes led a team of researchers collecting swabs from 41 such chimp nests in Tanzania and found they contained significantly fewer body bacteria than a bed in the average human household. “We found almost none of those microbes in the chimpa