I think the "paleo" comment is a bit unfair! ;-) And it has to be said that we do appear in fact to know with a good degree of certainty that at least one of t

I think the "paleo" comment is a bit unfair! ;-) And it has to be said that we do appear in fact to know with a good degree of certainty that at least one of the common cold viruses is very, very new in humans. OC43 (a coronavirus) almost certainly arrived in humans in the 1890s (and is now thought to be what caused the deadly "Russian Flu" pandemic). And we have another one to add now.