YOU might not believe it on a gloomy November morning, but scientists say we are born to laugh. According to their research, chuckling at a good joke or when someone tickles us, is instinctive. But crying when were sad, like other 'emotional vocalisations, is something we learn to do. The fact that a baby cries at birth is more likely to be down to the shock of birth or a reflex search for oxygen than sadness. For the study, Dutch scientists asked 16 volunteers to make the sounds behind several emotions without using words. Half the volunteers were deaf. The interpretations of sadness, terror, relief, anger, hilarity and other emotions were then played back to 25 volunteers with normal hearing, who were asked to name the emotion. Only laughter and sighs of relief were easily identifiable on the tapes of the deaf volunteers, New Scientist reports. All the other sounds, including cries of terror and sobs of sadness, were much easier to guess when made by volunteers without hearing problems. As the deaf volunteers have never heard others laugh, it suggests this is something we are born knowing how to do. But learning how to convey other emotions, such as sadness, comes with experience, an Acoustical Society of America conference will hear next week. Researcher Disa Sauter said laughter and smiling may have evolved to diffuse confrontation. 'Even other primates laugh, if you tickled a gorilla or orangutan.Professor Sophie Scott said: 'The finding makes sense. Laughter has been described as being more like a different way of breathing than a way of speaking. But Professor David Ostry said deaf people may simply learn to laugh by watching others do it. Daily Mail