On the Origin of Birds

Xiaotingia zhengi skeletonXU ET AL. NATURE

This year marks the 150^th anniversary of the discovery of one of the most iconic dinosaur fossils of all time: Archaeopteryx. Unearthed in 1861 in southern Germany, it has long been considered the missing link between dinosaurs and birds: it has the skeleton of a reptile—including a long bony tail and teeth—combined with what are considered hallmarks of modern birds—feathers and a wishbone.

But the discovery of a new bird-like dinosaur, Xiaotingia zhengi, in China threatens to dethrone Archaeopteryx as the most primitive of birds.

The inclusion of the new fossil in a comprehensive phylogenetic analysis of dinosaurs and early birds, published today (July 27) in Nature, resulted in a rearrangement of evolutionary relationships—removing Archaeopteryx from the avian family and placing it in a closely ...