_Eomaia_ and dung-eating vultures...

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

Two papers in the latest nature of probable interest to the list:

QIANG JI, ZHE-XI LUO, CHONG-XI YUAN, JOHN R. WIBLE, JIAN-PING ZHANG & JUSTIN
A. GEORGI. The earliest known eutherian mammal.  Nature 416, 816 - 822
(2002).
        Ji et al. describe mouse-sized _Eomaia scansoria_, a non-placentalian
eutherian from the Yixian.  Close to 100% complete in terms of the skeleton,
and a halo of fur preserved with it. Proportions of manus and pes resemble
those of living scansorial mammals.  Comes out as part of a basal polytomy
in Eutheria outside of Placentalia (the eutherian crown group).  Epipubic
bones are present, and there is a narrow pelvic outlet, so it may have had a
marsupial-like mode of reproduction.
        A tasty treat for small Yixian coelurosaurs...

ANNE WEIL. Mammalian evolution: Upwards and onwards (News & Views). Nature
416, 798 - 799 (2002).
        Accompanies the above.


NEGRO, J. J., J. M. GRANDE, J. L. TELLA, J. GARRIDO, D. HORNERO, J. A.
DONÁZAR, J. A. SANCHEZ-ZAPATA, J. R. BENÍTEZ & M. BARCELL. Coprophagy: An
unusual source of essential carotenoids.  Nature 416, 807 - 808 (2002).
        The brightly colored yellow head of the Egyptian vulture (_Neophron
percnopterus_) is found to be associated with another of its distinctive
attributes: its habit of eating ungulate dung.  Apparently the carotenoids
in the dung (which vertebrates are unable to synthesize, but which
accumately in ungulate crap from the plants they eat) are incorporated into
the integumentary tissue of the vultures, providing the pigment for their
skin.

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796