The skeletons of Tyrannosaurus rex are terrifyingly huge – for example the “Tristan” specimen in the Berlin Museum of Natural History. In the past, however, various bones were found that look as if they came from miniature editions of the T. rex .
For decades, researchers have been arguing whether these are independent, smaller species or early offspring by the famous predatory dinosaur. Holly Woodward from the Oklahoma State University Center for Health Sciences in Tulsa has now examined the bones of two specimens of such “dwarf tyrants” (Nanotyrannus), the horse-sized skeletons of “Jane” and “Petey” from the Burpee Museum of Natural History in Illinois, USA ,
Your research team comes to the conclusion that the skeletons are from young T. rex , not of adult specimens of other species. The unwieldy, bulky tyrannosaurs were agile, slim and light-footed hunters with knife-like teeth in their youth, the researchers write in the journal “Science Advances”.
With 15 T. rex were hardly bigger than a horse
Apparently Tyrannosaurus rex went through a phase of exponential growth towards the ten meter long giant dinosaur with bone-grinding teeth quite late in his life. In this way, young animals would have taken other niches in the ecosystem than the adult ones and thus avoided competition.
The knowloedge The development of the giant lizards is often incomplete, as museums prefer to collect the largest, most impressive finds of a kind, the researchers explain. Many saurians therefore lacked young specimens, the examination of which would indicate that the primeval lizards had grown up. The T. rex was no exception – and “Jane” and “Petey” were a great stroke of luck. They were probably about 13 and 15 years old when they died.
eating machine only with 20 Full grown years
In their youth the predatory dinosaurs apparently grew at rates similar to those of today's birds and mammals the researchers from the bone analysis. However, there were probably big differences from year to year depending on the food supply. The dinosaurs were probably only grown up to 20 years, whereby their physical appearance immensely changed from the agile hunter to cumbersome eating machine changed. Annett Stein (dpa)