Cancers are an ancient phenomenon in nature. A team of Belgian researchers from the Vrije Universiteit Brussel (VUB) and Université de Liège (ULiège) has now demonstrated that long-necked dinosaurs known as sauropods, the largest animals that ever walked the earth, were also susceptible to bone diseases such as malignant cancers.
Benjamin Jentgen, a PhD student at VUB and ULiège, examined bone samples from two early sauropods. In the well-preserved tissues he found structures that in all likelihood indicate cancer. “The animals show different types of infection,” says Jentgen. “In an Early Jurassic Isanosaurus from Thailand (±200 million years old), the animal produced some sort of microscopic bone spurs on the surface of its humerus. It died shortly afterwards. Such spurs are typically associated with malignant tumours and thus fit into the picture of a fatal bone cancer.”
The researchers also describe a second sample, this time of a Spinophorosaurus, from the Jurassic period in Niger. This animal, too, has such needle-like bone structures, but survived the infection and continued to grow normally afterwards. “This may have been a reaction to a benign tumour, or possibly a viral infection, but the skeleton of the animal in question is fairly complete and shows several other pathologies such as fractures. This means that this Spinophorosaurus suffered several traumas during its life,” Jentgen says.
The samples of these dinosaurs were taken many years ago by Koen Stein, a palaeontologist at VUB and co-author of the study. “When I took the samples in 2008 as part of my own doctoral research, I immediately noticed these abnormal tissues, but I never really had the time to study the anomalies in detail. It was clear that it was a disease, but without molecular testing, it is difficult to make a diagnosis. It was thanks to Benjamin, who plodded through the medical and veterinary literature, that we were able to identify the possible causes of the foreign bone tissues in these dinosaurs,” says Stein. Valentin Fischer, professor of palaeontology at ULiège, says: “This study is important because fossils with signs of cancer are extremely rare. It also seems that many pathologies in fossils go unnoticed, because it is thanks to the sampling that we found the symptoms. There were no clear indications of disease on the surface of the bones.”
The results were published in Philosophical Transactions of the Royal Society B http://dx.doi.org/10.1098/rstb.2019.0143
Dr Koen Stein
FWO postdoctoral researcher
Earth System Science - AMGC
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