YONG XU Chinese Academy of Sciences

Paleontologists working in northeastern China have uncovered yet another extraordinarily well preserved bird fossil. The crow-size creature, dubbed Jeholornis prima, lived during the Early Cretaceous period, and its remains provide rare insight into what early birds ate.

According to a report published today in the journal Nature, the beast¿s stomach contains more than 50 intact plant seeds--the first direct evidence of early avian seed-eating. Other clues to what the animal ate come from the skeleton itself. Zhonghe Zhou and Fucheng Zhang of the Chinese Academy of Sciences in Beijing, the researchers who describe the fossil, note that features of the jaws, teeth and hyoid bones are consistent with a seed-eating habit.

Whether Jeholornis obtained the seeds from cones in trees or on the ground is unclear. But its body appears to have been well adapted to powerful flight and to perching in trees. This is surprising, Zhou and Zhang remark, considering how primitive a bird it is. The fossil also exhibits a long, bony tail similar to that of dromaeosaurs, thus bolstering the evolutionary link between birds and theropod dinosaurs.

"This discovery, together with many others in recent years," the authors conclude, "suggests that by the Early Cretaceous, early birds had not only diverged significantly in morphology, size, and ecology, but had also differentiated with respect to feeding adaptation."