The nearly complete skeleton of the haplocheirus was uncovered in ancient river deposits in the Junggar Basin of northwestern China's Xinijiang region in a joint digging campaign by Chinese and US scientists. At two meters in length, it is the largest Alvarezsauride ever found. But not only his body measurements differentiate him from his descendants: These have on very short forelegs a sharp claw next to two completely receded toe remnants, in the ancestor, there are three toes, of which the middle, however, is already significantly extended. The strong arm stubs with the sharp sickle claw were used in the view of the scientists to break up hard termite buildings. The Latin "sollers" means "sent": Haplocheirus could reach with his fingers.
"Haplocheirus is a transitional fossil. It shows how, at an early stage of evolution, the bizarre claw of the later Alvarezsaurids evolved from long-living predatory dinosaurs, "explains Jonah Choiniere of George Washington University in Washington. "And it confirms our prediction that this species already existed in the late Jurassic period." The paleontologists team discovered more extraordinary finds in its excavations: Among other things, the oldest dinosaur with horn-like humps called Yinlong downsi and the oldest were excavated Tyrannosaurus, the three meter long predator Guanlong wucaii.Jonah Choiniere (George Washington University, Washington) et al .: Science, doi: 10.1038 / nature08740 ddp / science.de? Rochus Rademacher advertisement