Female tyrannosaurus
2005/06/07 Roa Zubia, Guillermo - Elhuyar Zientzia
In the mountains of Montana a fossil of a female tyrannosaurus has been found. Scientists have discovered it by cutting fossilized bones. The bones of the Tyrannosaurus are approximately the same as those of the current ostrich, and is that, by comparing the two species, they have managed to know that the dinosaur was female. Ostrich (and emu) females have a special bone marrow to develop the egg: they have many small blood vessels to carry calcium into the egg. Males, however, do not have that bone marrow. Inside the bones of the tyranosurum of Montana has been found the same structure as female ostriches, so scientists have deduced that it was female. If they were male they could not know, since the lack of this bone marrow may be due to years of degradation.
