Asked by: Annie Trolley, Taunton
Scents provoke strong responses, and not everyone responds in the same way: some people love the smell of geraniums, others feel queasy just thinking about it. But research at the London School of Hygiene and Tropical Medicine has found that some things universally provoke disgust, and they include many smelly things like rotting meat and bodily excretions. According to Dr Valerie Curtis, who led the study, this supports the theory that our disgust at certain smells is an evolved response that protects us against sources of infection. Not all researchers agree that disgust is hard-wired into our genes, though: some think we acquire our reactions during early childhood.
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