RE: Non-dinosaurian surprise

[Jeff Hecht <jeff.hecht@sff.net>]

At 5:53 PM +0100 12/13/06, evelyn sobielski wrote:
>Oh man, this will put so much water on the mills of
>the "waitoreke" entusiasts... in any case, does
>"mouse" imply a relationship with rodents? That would
>be a surprise indeed, but not shocking; after all
>there are scores of endemic rodents in Australia too.

The abstract in Proceedings of the National Academy of Sciences says:
"A partial relatively plesiomorphic femur and two
autapomorphically specialized partial mandibles represent at least
one mouse-sized mammal of unknown relationships. The material
implies the existence of one or more ghost lineages, at least one of
which (based on the relatively plesiomorphic partial femur)
spanned the Middle Miocene to at least the Early Cretaceous,
probably before the time of divergence of marsupials and placentals
125 Ma. Its presence in NZ in the Middle Miocene and
apparent absence from Australia and other adjacent landmasses at
this time appear to reflect a Gondwanan vicariant event and imply
persistence of emergent land during the Oligocene marine transgression
of NZ. Nonvolant terrestrial mammals disappeared from
NZ some time since the Middle Miocene, possibly because of late
Neogene climatic cooling."

A phylogeny groups it between Eutriconodontans and multituberculates, closer to 
the multis. Assuming that's right, its lineage goes back a long ways.

-- 
Jeff Hecht,    science and technology writer
525 Auburn St.,   Auburndale, MA 02466   USA
V 617-965-3834  F 617-332-4760  e-mail jeff@jeffhecht.com