a Short, cone-shaped, pointed beaks. The Clamps remind finches to that of a book, so now you have a grain-eaters. They are, however, about 50 million years old, and birds on both sides of the Atlantic, they took advantage of. A group of paleo-ornithologist Gerald Mayr from the Senckenberg research Institute in Frankfurt have described the two new species recently in the journal “Current Biology”.
grain-eaters, omnivores
While Eofringillirostrum boudreauxi lived there, where today the Green River in the U.S. state of Wyoming, flows South to the Colorado River, sought Eofringillirostrum parvulum its grains about the same time, where in the Messel pit near Darmstadt, Germany until 1971, oil-Shale was mined.
Both ” have the typical Beak of grain eaters, such as our today’s finches,” explains Mayr. The researchers have discovered on both sides of the Atlantic, by far, the oldest known grain-eaters. Finches have similar beaks, appeared as recently as ten million years.
both species belong to an extinct group that was with the ancestors of the passerine birds – of today’s most species – rich order of birds is closely related. Just like today’s birds do not appear before 50 million years ago – i.e. about 100 million years after birds appeared at all on the image area of the Evolution in very different habitats to be home. Species had specialized in a number of food sources. In addition to those grain eaters, there were species, which sucked obviously nectar from flowers. “Another group had a long and narrow beaks similar to today’s blackbirds and Starlings,” says Mayr. This suggests omnivorous, the berries today, fruits, worms, beetles, snails, millipedes, spiders and insects including their larvae, but also small vertebrates such as lizards eat.
toes count
The diversity is surprising. And all the known members of this group are characteristics that are missing in the present-day passerine birds. The feet include, in addition to a few tiny Differences in the skeleton: “Today, all the passerine birds, three forward and one rear facing toe,” while the Extinct two toes were to the front and rear, explains Mayr. The entire variety of these with two toes and a number of other specialties provided group died out and was replaced by the present-day passerine birds. “Has survived, apparently only a single group that was in Australia and new Zealand at home and in front of around 30 million years ago for the first Time in the Rest of the world showed up,” says Mayr.
These real-passerine birds arose before about 47 million years ago the land mass of Australia, report by Carl Oliveros and Brant Faircloth from Louisiana State University in Baton Rouge, together with colleagues this week in the journal PNAS. The researchers are based on analyses of the genetic material today of live birds and match them with the fossil record without genetic investigations. Therefore, the passerine birds developed initially in Australia and new Zealand. In the Rest of the world they came, as before, around 30 million years ago, huge ice sheet of the Antarctic is covered and the world for some millions of years, an ice age climate. An important role for the dissemination of the singing of birds has also played the substantial or complete Inundation of new Zealand, with around 23 million years ago. In addition to such geological and climatic changes should also have been a number of other factors important for the Evolution of the living around 6000 in passerine birds, species, close, Oliveros, Faircloth and her colleagues from their molecular biological studies.
Airy home
So the 50 million years ago is still so successful the group disappeared, do not know Gerald Mayr and his colleagues so far. May be the two rear-facing toes played a role. Today they occur only in some bird groups such as parrots and woodpeckers. These breeding caves mostly in the tree – a resource that is highly competitive. Mitinteressenten about bees, small mammals and snakes. The modern passerine birds go the with the exception of the Tits mostly out of the way, by building in trees, bushes or rough terrain to their nests. These are often not even for the nest robbers. For most of the small passerine birds with your, therefore, limited defense options that could be a important advantage and the secret of their success until today.