Scientists in New Zealand have devised a surprising new strategy for fighting climate change: potty-training cows. That might sound strange, but cattle waste contributes to the creation of greenhouse gases, which trap heat in Earth’s atmosphere. If cows peed in a stall, though, it could prevent some of the gases, such as nitrous oxide, from making their way into the environment, says Douglas Elliffe, a scientist on the team. Elliffe’s group selected 16 calves and offered them food rewards for peeing in a pen designated as a bovine latrine. After about 15 days, many cows learned to associate peeing there with receiving a treat and held it in until they made it to the latrine. From there, the urine could be collected and disposed of, or potentially turned into fertilizer. Next, the team wants to share the training with real farms. Elliffe says that when he tells people about the research, they often laugh, but once they understand it, “they start taking it seriously and see how useful it could be. Sometimes the craziest ideas can be the best ones.”