Scientists were honoured at the annual Ig Nobel Prizes for a range of unusual but genuine research, celebrating studies that first make people laugh, then think. The ceremony, held in Zurich, took place outside the United States for the first time in its 35-year history, reportedly due to concerns that some winners might struggle to obtain US visas. Organised by the Annals of Improbable Research, the awards remain distinct from the actual Nobel Prizes, which are due to be announced in October.

This year's winners included research into cockroach milk, the evolutionary history of kissing, and the use of underwear to test soil health. Other honoured studies examined why wealthier people are more prone to unethical behaviour, the correct technique for blowing one's nose, and what provokes snakes to bite when stepped on. Further prizes went to work on splash-free urinal design, 3D printing using dead mosquitoes, and findings that parents enjoy the smell of their newborns but not their teenagers. Researchers also traced kissing back roughly 21.5 million years, suggesting Neanderthals may have practised it too. Winners receive a trophy resembling a cross between a mushroom and a human foot, while the audience traditionally pelts the stage with paper aeroplanes.