A Primitive Enantiornithine Bird and the Origin of Feathers
Fucheng Zhang,*
Zhonghe Zhou
A fossil enantiornithine bird, Protopteryx fengningensis
gen. et sp. nov., was collected from the Early Cretaceous Yixian Formation of Northern China. It provides fossil evidence of a triosseal
canal in early birds. The manus and the alular digit are long, as in
Archaeopteryx and Confuciusornis, but are
relatively short in other enantiornithines. The alula or bastard wing
is attached to an unreduced alular digit. The two central tail feathers are scalelike without branching. This type of feather may suggest that
modern feathers evolved through the following stages: (i) elongated
scale, (ii) central shaft, (iii) barbs, and finally (iv) barbules and
barbicel.
Institute of Vertebrate Paleontology and Paleoanthropology,
Chinese Academy of Sciences, Post Office Box 643, Beijing 100044, China.
*
To whom correspondence should be addressed. E-mail:
fuchengzhang{at}yeah.net