I see that: "I assume you question the validity of evolution." Was correct. Then there is no sense in pretending. You will not accept the time line of mammalian evolution, so what is the point in discussing it any further. I can not present the physical evidence to you. You will need to educate yourself and determine if it is acceptable to you or not. But for what it's worth here: http://en.wikipedia.org/wiki/Evolution_of_mammals "These changes forced the Mesozoic mammaliforms ("nearly mammals") into nocturnal niches, and may have contributed greatly to the development of mammalian traits such as endothermy, hair and a large brain" "The first clear evidence of hair or fur is in fossils of Castorocauda, from 164M years ago in the mid Jurassic."