Apparently saliva contains natural painkillers which is interesting to think about as an incentive for animals to lick their wounds that evolved: https://www.ne

Apparently saliva contains natural painkillers which is interesting to think about as an incentive for animals to lick their wounds that evolved: https://www.newscientist.com/article/dn10514-natural-born-painkiller-found-in-human-saliva/ https://www.newscientist.com/article/dn10514-natural-born-pa...