After a study of the holes in the jaw of Sue, the Tyrannosaurus rex skeleton on display at the Field Museum in Chicago, a team of scientists have concluded that a single-celled parasite in a paleolithic turn might have spelled doom for the 13-foot-tall Tyrannosaurus rex!

Going by the paper published in the September 29 edition of the online science journal PloS One, the international team of scientists opined that the parasite - which is a kin of the lowly Trichomonas microbe that infects modern birds of prey - may have not only killed off Sue, but also many other tyrannosaurids.

Mentioning the reason behind Sue's death, the lead author of the paper Ewan Wolff - a paleontologist at the University of Wisconsin-Madison - said: "It's a distinct possibility that Sue died of starvation by a substantial infection in the back of the throat brought on by a tiny parasite."

According to Wolff, the parasite, Trichomonas gallinae, settled in the back of the throats of Sue and nine other Tyrannosaurs who also had similar telltale holes in their jaws. As a result, the inflammation that resulted gradually damaged the jawbones of these creatures.

Wolff theorized that with the worsening of the throat infection, swelling made the esophagus "narrower and narrower," and the subsequent "starvation" was the ultimate reason behind the death of these gigantic creatures!