[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Downy early birds



        Just noticed that Hou (1995) reports down feathers, as well as 
contour feathers, from specimens of Confuciusornis.  Isolated down feathers
from the Lower Cretaceous (Aptian) of Brazil have also been recently 
described (Kellner et al 1994).  Since down feathers function as thermal
insulators (Gill, 1990), the occurrence of down feathers in Lower
Cretaceous birds suggests that high resting metabolic rates and endothermy
were intrinsic features of basal avian evolution.  If down feathers
represent a shared derived character of Confuciusornis + modern birds,
then it is possible that down feathers may have been present even in birds
similar to Archaeopteryx.

REFERENCES
        Gill, F.B. (1990).  Ornithology.  W.H. Freeman & Company, New York.
        Hou, L. (1995).  Morphological comparisons between Confuciusornis
and Archaeopteryx.  In Sixth Symposium on Mesozoic Terrestrial Ecosystems
and Biotas, Short Papers (Sun, A., & Wang, Y. eds), pp. 193-201.  China
Ocean Press, Beijing.
        Kellner, A.W.A., Maisey, J.G. & Campos, D.A. (1994).  Fossil down
feather from the lower cretaceous of brazil.  Palaeontology, 37 (3), 
489-492.

Guy Leahy
n9435712@henson.cc.wwu.edu
Dept. of PEHR
Western Washington University
Bellingham, WA 98225