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Re: K-T mammals



> Hey, we all know the extent of archosaur devestation over the K-T
> transition, but what about mammals?  What mammalian groups died after
> the K-T calamity?
> Quite a few, I assume.

Looks like it. I have no idea about multis
(www.paleocene-mammals.de/multis.htm only says "Although some lineages
became extinct during the faunal turnover at the end of the Cretaceous,
multituberculates managed very successfully to cross the K/T boundary and
reached their peak of diversity during the Paleocene"), but Metatheria is a
clear case -- Deltather(your favorite ending here) died out (whenever the
exact date, see below), Stagodontidae did (the Tasmanian Devil analogs of
Asia and NA), Pediomyidae (a North American group) did (except if the report
from the Paleocene of SA is confirmed), and I don't know if the Tertiary
Metatheria of Laurasia and Africa belong to Alphadontidae --
www.paleocene-mammals.de/marsupials.htm indeed says they do. However,
www.carnegiemuseums.org/cmnh/vp/paleocene.html lists "didelphid" marsupials
as immigrants to NA -- from Asia, I assume -- in the late Paleocene, so
maybe Alphadontidae died out completely in NA. Except them, only the small
branch that emigrated to SA, namely the ancestors of crown-group
Marsupialia, survived. The situation among Eutheria may be more similar than
thought for quite some time, but the fossil record appears to be worse. No
Eutheria with epipubes are known from the Cenozoic; the group that includes
Zalambdalestidae, Asioryctitheria, *Ukhaatherium*, *Kennalestes* and
possibly Zhelestidae retained them and is known from the LK (Coniacian to...
late Campanian? early Maastrichtian?) but not the Cenozoic. Leptictida (like
*Gypsonictops*) and Palaeoryctidae (like *Cimolestes*) survived (and died
out in the Oligocene); they may be outside the crown-group Placentalia or at
least outside the crown-group Laurasiatheria, as the *Eomaia* paper finds
them outside of (*Protungulatum* + *Erinaceus*), but that paper admits
itself that it doesn't include enough certain crown-group mammals to tell
anything for sure. (We've had the discussion about how old *Protungulatum*
is www.paleocene-mammals.de/condylarths.htm... not to mention
*Purgatorius*.) -- Among Triconodonta, representatives are known from the LK
of NA and SA. How old is the former (*Alticonodon*)? It doesn't appear in
www.dinosauria.com/jdp/misc/hellcreek.html#mammals. One SA dryolest(o)id(an)
is known from the Paleocene (*Peligrotherium*). A highly derived (probable)
docodont has been found in the LK of SA (*Reigitherium*), but none from the
Paleocene, but given that amount of fossils -- a scrap of dentary, of
course -- this may or may not mean anything. Gondwanatheria, whatever that
is, survived (in SA -- elsewhere [India, Madagascar] no Paleocene strata are
known IIRC). Among Australosphenida, only Monotremata are known from the
Paleocene, but again fossils are so scarce that anything can be interpreted
into their distribution (IIRC not one LK australosphenidan is known,
right?). Spalacotheriidae (like *Zhangheotherium*) seem to stop in the
Cenomanian... or Turonian... or maybe Campanian?
http://home.arcor.de/ktdykes/symmetro.htm. No idea what *Chronoperates* from
the Paleocene is www.cmnh.org/fun/dinosaur-archive/1997May/msg00778.html. To
step outside Mammaliaformes, the last tritylodontids known at the moment are
from the EK of western Siberia and Japan and may have died out anytime
later. Who knows.

I've found this here www.ucmp.berkeley.edu/museum/75th/ab5.html.
Unfortunately this is just an abstract for a poster session, so there's no
paper.