So much is still unknown about dinosaurs, but a fossilized Tyrannosaurus rex bone found in Montana could provide new insights.
In a recent study, researchers from North Carolina State University and North Carolina Museum of Natural Sciences have confirmed the discovery of a medullary bone which is female-specific and formed around the time of reproduction.
This determination was made through a chemical analysis of the components.
Because the tissue only develops before or during the egg laying process, they have concluded that the T. Rex was likely pregnant at the time of death.
Adding to the excitement is the possibility that DNA could still be present, with Lindsay Zanno, one of the paper's authors telling Discovery News, "We have some evidence that fragments of DNA may be preserved in dinosaur fossils, but this remains to be tested further."
Regardless of that outcome, she says that the fragment could help with gender identification which has been a challenge for researchers.
The pregnant dinosaur is believed to have lived 68 million years ago.
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