Researchers have found a million years old tumor attached to the teeth of a non-mammal species which lived approximately 255 million years ago.
The discovery is the first of its kind and could come to offer precious information about the development of mammal features.
Research on the matter was carried out by a team of University of Washington or UW paleontologists. Led by Megan White, a UW graduate student, the study was published earlier this week.
Thursday, December 08, saw the release of the scientific letter as it was published in the Journal of the American Medical Association Oncology. It was titled “Odontoma in a 255-Million-Year-Old Mammalian Forebear”.
The million years old tumor was discovered whilst studying a gorgonopsian fossil. As a species believed to have lived some 255 million years ago, the gorgonopsian pre-date dinosaurs.
Gorgonopsians were amongst the largest predators of their epoch, the Permian. Classified as mammalians, this means that the species is closer to mammals than to dinosaurs or reptiles.
Previous studies revealed that the species had a carnivore diet. This was established thanks to their enlarged canine teeth. Similar teeth have been observed in other species such as the Siberian tiger.
The tumor was found during one such observation of a fossil’s mandible. As it was determined to be an odontoma or a benign tumor, it is nonetheless an important find.
Its fossil base was discovered back in 2007, in southern Tanzania in the Ruhuhu Valley.
Odontomas are described as being abnormally large masses of calcified dental tissue. The description, which was determined by the National Institutes of Health, also links it to teeth development.
As such, the benign tumor leads to an unusual tissue growth. It has also come to be considered the second-most common tumor type to affect teeth development.
Still, the current odontoma is a very rare find. No previous non-mammal species have presented this tumor, not to speak of millions of years old ones.
Judy Skog, the National Science Foundation Division of Earth Sciences program director went to explain. According to Skog, the oldest such million years old tumor had been previously spotted in mammal fossils.
However, the respective fossil was just about 1 million years old. As such, the period difference between the two tumors really has no reason for being mentioned.
The odontoma’s discovery in such an old fossil can bring fundamental changes in the area. Skog pointed out that previous theories linked the tumor’s cause with modern species properties.
However, this million years old tumor shows that odontoma is not solely tied to them.
According to the research lead, Whitney, the study was seeking to determine the evolution of mammalian features.
Mammals are believed to have evolved some 100 million years ago. As such, the study sought to understand the possible features transmission from the former to the latter.
Whitney also stated that she wished to determine the gorgonopsians jawbone structure by looking to see who it resembled most.
Mammals have a tough and flexible string-like tissue that folds their teeth. Most reptile teeth are fused directly to their jawbones.
As the current odontoma is the oldest such tumor discovered in a gorgonopsian, it is not the oldest on record.
The as yet oldest registered tumor was found in a 300 million years old fish. A further such cancer trace may have also affected a 350 million years old fossil.
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