This week, scientists announced the discovery of two fossil specimens from China that they believe to be records of the oldest member of Ornithuromorpha, the branch of the avian evolutionary tree that contains modern birds. The new species, named Archaeornithura meemannae, was unveiled in a recent study published in Nature Communications. Previously, the oldest-known Ornithuromorpha dated back 125 million years. But the new species is nearly 5 million years older. Even with this blip in the evolutionary timeline, however, there are fossilized birds that are even more ancient. Archaeopteryx, which disappeared about 145 million years ago, still holds the record. “Currently, Archaeopteryx is still the oldest and most primitive bird," says Min Wang, leader of the study and paleontologist at the Chinese Academy of Sciences in Beijing, China. The new fossils are characterized by feathers and short tails—defining features for Ornithuromorpha. “The relatively long legs and...