Newly analyzed fossils could place the first appearance of modern birds back a ways, as they date back 130 million years.
According to BBC News, authors of a study published in the journal Nature Communications detailed Ornithuromorpha fossils, which would push back the emergence of the first "modern birds" about five million years.
"All living birds belong to a group called the Ornithuromorpha, and until now the oldest species known was 125 million years old," study lead author Min Wang, of the Chinese Academy of Sciences told the Guardian. "This new species comes from deposits that are more than 130 million years old, so it pushes back that date by at least 5 million years."
Archaeopteryx was previously believed to have been the first bird because it lived around the time at the end of the Jurassic Period where dinosaurs began their evolution into what would eventually become birds. But many and more scientists are considering the species a dinosaur with bird characteristics. Ornithuromorpha may not have flown great distances, but they appear to be the precursor to modern birds.
"The new bird is quite derived and has many advanced features of modern birds, and thus is far away from the transitional history of dinosaurs-birds," Wang told the Washington Post. "The most primitive bird of Ornithuromorpha is most likely from older deposits than what we discovered now."
For their study, the researchers aged their fossils by determining how old the surrounding rocks were.
"This finding is important because it comes from such old rocks and the species is already quite advanced in its group," Gareth Dyke, a paleontologist at the University of Southampton, told the Guardian. "It suggests that in the early Cretaceous, all the major groups of birds had already evolved and diversified."
