The sample size of six fossils is small, encapsulating only a particular time period, region, and subset of all early mammals, he says– though adds that’s not abnormal for paleontology.

Small mammals like mice are dependent on trees and ... “The take-home message of all the research we are doing is that individuals are important. There’s a big push in the science community ...

not fish and like all mammals, they have hair. Not much hair, just a few bristles, but it’s still there. Some mammals are small and live near you. Like dogs and cats who have soft hair or fur.