>> The genus _Rattus_ has 137 species and is known to have originated just
>> before the middle ages. (see L.Drew Davis A list of Observed speciation
>> events" Talk.Origins archives. and G. H.H. Tate, "Some Muridae of the
>> Indo-Australian Region," Bull, Amer. Museum Nat. Hist. 72: 501-728, 1963)
Not that affects your point that this is a known example of speciation,
but Rattus has been around a lot longer than that. Davis was referring
only to rats in Indonesia and Malaysia.
-- Jim Foley Symbios Logic, Fort Collins, COJim.Foley@symbios.com (303) 223-5100 x9765 I've got a plan so cunning you could put a tail on it and call it a weasel. -- Edmund Blackadder