An ancient dinosaur-era bird turns out to have two tails, one maybe for flying while the other for showing off. Paleontologists suggest that the early bird gets two tails? A 120-million-year-old bird sported a long tail and a second, unexpected tail frond, the discovery points to a intricate evolutionary path for the tails we see in birds today. The 2nd oldest known bird, Jeholornis, lived in what is today China, along with a trove of other feathered dinosaurs uncovered in the region over the last decade. Fossils explain that Jeholornis was turkey-size, had claws on its wing forelimbs, and possessed 3 small teeth in its lower jaw, and thought to sport only a long fan feathered tail at its back end. Therefore; paleontologists are claiming discovery of a second tail frond adorning the bird. It is believed that 'two-tail' plumage of Jeholornis is unique. Of 11 Jeholornis fossils that retain evidence of ancient plumage, six have signs of this frond of eleven feathers, which would have jutted above the bird's back at a jaunty, upright angle in a "visually striking" manner.
Visibly the display aspect of the frond would have been irrefutable. It calls to mind living birds, even peacocks, which display broad plumes of feathers. In peacocks and other birds, such feathery skin textures are more for attracting the attention of potential mates than for any functional purpose. Male birds are the ones with the striking plumage, and perhaps only one sex of Jeholornis sported the eye-catching tail fronds.
Jeholornis is not thought to be directly related to modern birds, which seem to have evolved from a different line of early avians. The tail frond may have played a stabilizing role in the flight of these early birds and that if the arrangement of feathers had proven advantageous enough, modern birds might have evolved to sport such two tailed features. The fronds are flattening to offer a streamlined appearance when the bird was in flight. Other researchers aren't convinced the newly discovered tail frond played much of a role in aviation, however. Feathering in the new specimens is quite interesting; it could have been a peculiarity of the one species, as the authors note. Perhaps the frond simply evolved as an easy-to-notice "sexual display" flaunted by these early birds