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2 "new" refs.

Finds from the Ferris Formation in the Hanna Basin, southern Wyoming tell
an interesting story of "Vertebrate Faunal Changes through Lancian and
Puercan Time in Southern Wyoming" ( Lillegraven, J.A. and J.J.
Eberle, Journal of Pal. V. 73, No. 4 1999, pages 691-710).

- non-avian dinosaur diversity remains high up to the boundary (though
boundary is vague)
- condylarths (including Arctocyonidae, Periptychidae, and Mioclaenidae)
appear in the record "just as" non-avian dinosaurs disappear.  They are
apparently immigrants because there is no record of them prior to this

Second ref. Eberle, J.J. 1999 Bridging the transition between Didelpodonts
and Taeniodonts, Journal of Paleontology. 73:(5)936-944

- describes a coyote-sized mammal within about 400,000 years of the K/T
boundary (Alveugena carbonensis)

I have never received a response to the following question: speaking
statistically, isn't it likely that if a very rare animal is found in a
certain strata, that its range is probably broader than that strata.
Specifically, isn't it probable that this animal was present before the
K/T, 400,000 years earlier? (Personally, I don't think this likely.  I'm
just trying to get at the statistical argument.)