Definitely yes, no and perhaps. Keeping in mind skeletons aren't exactly common, Mongolian Upper Cretaceous multituberculates tend to be seen as terrestrial, as is the case for a "symmetrodont" called /Zhangheotherium/ from Liaoning. /Haldanodon/ -an Upper Jurassic docodont from Portugal, got accused of desmane-like interests in burrowing and swimming, tastes then more spectacularly demonstrated by its earlier relative /Castorocauda/. And various mammals have been accused of having arboreal, or at least clambering interests: eg. /Henkelotherium/, /Eomaia/ and /Sinodelphys/.
A complicating factor is, should you have a head-body length of say ten centimetres, clambering skills are liable to be helpful when travelling across a bit of ground humans stupidly think of as being flat. Also, of course, as many taxa are based upon isolated teeth or even some teeth on a small bit of jaw bone, then evidence of relevance for such matters is slightly less then minimal.
Cheers Trevor Dykes On 31.10.2011 23:37, Anthony Docimo wrote:
Do most of the known Mesozoic mammals exhibit evidence of their living in
trees, on the ground...or is it like with Archie, and the evidence could be
interpretted either way?
(_Volatacotherium_'s a definate tree-dweller, I know; _Repomanus_(sp) seems too
bulky to be very good at climbing)