This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: The Hammerschmiede clay pit near Pforzen in the eastern Allgäu is famous for its wealth of finds: Besides fossils of two early anthropoid apes, the remains of numerous vertebrate species have been uncovered in 11.6-million-year-old river sediments—but until now, very few birds. Gerald Mayr of the Senckenberg Research Institute and Natural History Museum Frankfurt, excavation leader Dr.
Thomas Lechner of the Hammerschmiede, and Professor Madelaine Böhme of the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen and the Tübingen Cluster of Excellence TERRA has discovered and described a further six bird species: cormorants, a loon and an eagle, including two genera and species new to science. "Birds are among the rarest fossil finds in the Hammerschmiede. Only 1 in 40 bone finds is from this class of vertebrates; today, they make up the greatest number of species on Earth," reports excavation leader Lechner.
So far, the researchers have documented the presence of darters, a giant crane and several waterfowl, including the unusual Allgoviachen tortonica and a dwarf duck. The study was published in the Swiss Journal of Palaeontology. Today, cormorants still dive for fish along ocean coasts and in some inland waters.
The newly identified genus and species of cormorant, Bavaricarbo brevirostris (Bavarian short-billed cormorant) from the Hammerschmiede, is the most recent known representative of the extinct original stem group of cormorants. Mayr says, "In Bavaricarbo, the bones of the humerus, which make up part of the wing, and the tarsometatarsus are formed differently from those of modern cormorants. Therefore, Bavaricarbo could presumably fly better than modern cormorants but probably could dive only in shallow waters such as the river by the Hammerschmiede." A second, still unnamed species of cormorant from the Hammerschmiede is the size of today's pygmy cormorant (Microcarbo pygmaeus).
There have been numerous cormorant finds, but so far only one humerus bone of a loon. "However, if we combine these with the similarly frequent finds of the large darter Anhinga pannonica, it is clear that the rivers of the Hammerschmiede area were dominated by fish-eating diving birds," Böhme says. Bird finds from the Hammerschmiede also often include the talons of Accipitridae, a family of hawks.
"We discovered a lower-leg bone of a hawk that differs in essential details from present-day species and is vaguely reminiscent of an osprey," Mayr reports. The research team named the newly discovered genus Mioaetus—"eagle from the Miocene"—and, in honor of the community and inhabitants of Pforzen, gave it the species name Mioaetus pforzenensis—the Pforzen Miocene eagle. The form of the tarsometatarsus indicates that the bird probably had a wingspan of more than 1 meter (3.3 feet) and also presumably caught fish in its talons, Böhme says.
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