Scientists Discover First Evidence of Deadly Cancer in Dinosaur
2020-08-10
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1Canadian researchers say they have discovered the first known case of a dinosaur suffering from a deadly cancer.
2The evidence came from a fossil leg bone discovered in Alberta, Canada in 1989.
3The fossil was from a dinosaur called Centrosaurus.
4It was a four-legged plant eating animal about 6 meters long that lived between 76 and 77 million years ago.
5Examinations of the fossil showed the lower leg bone, called the fibula, was badly malformed.
6The scientists thought this was likely caused during the healing process of a broken leg.
7But new studies of the fossil led researchers to believe the malformation was probably caused by an aggressive bone cancer called osteosarcoma.
8The research team included medical professionals who study and diagnose cancers in humans.
9The findings were recently reported in the medical publication Lancet Oncology.
10The publication describes osteosarcoma as a severe and deadly bone cancer "with a worldwide incidence of 3.4 cases per million people per year."
11The cancer often takes the form of a disorganized bone growth that generally strikes children or young adults.
12The cancer can spread through bones and to other organs.
13The researchers said the latest examinations of the fossil showed the dinosaur leg bone contained "a massive...tumor."
14They said they were able to confirm that the growth was a tumor by using computed tomography, or CT, images.
15CT technology uses X-rays and a computer to make detailed pictures of bones, organs and tissue inside the body.
16The team compared a normal Centrosaurus fibula to the malformed one.
17They also compared the malformed dinosaur bone to a human fibula with a confirmed case of osteosarcoma.
18The comparisons led the researchers to confirm a likely case of osteosarcoma.
19Experts say since most tumors form in soft tissue that does not easily fossilize, there is little evidence of cancer in the fossil record.
20One of the project leaders was David Evans of the Royal Ontario Museum in Toronto.
21He spoke to Reuters news agency about the finding.
22He said one of the strongest pieces of evidence was that the cancer was also found in the outer layer of bone.
23This does not support the theory that the malformed leg was caused by a healed break.
24"This remarkable find shows that no matter how big or powerful some dinosaurs may seem, they were affected by many of the same diseases we see in humans and other animals today, including cancer," Evans said.
25He added that the Centrosaurus linked to the fossil "was likely weak and lamed by the cancer" before its death.
26Cancer, however, may not have killed the dinosaur.
27Evans said the fossil was found in a large collection of Centrosaurus individuals.
28This suggests that they all died as a group after being caught in a flood.
29Another lead researcher was Dr. Mark Crowther, a professor of medicine at McMaster University in Ontario.
30He said the new discovery was only made possible through the use of modern methods and an expert medical team representing several fields.
31"Here, we show the unmistakable signature of advanced bone cancer in a 76-million-year-old horned dinosaur - the first of its kind. It's very exciting," Crowther said.
32He added that the finding "speaks to the biology of cancer."
33This means cancer is not new and probably has been happening through time as "an expected complication in all animals."
34Evans added that while dinosaurs might be seen as mythical creatures, "they were living, breathing animals that suffered through horrible injuries and diseases."
35I'm Bryan Lynn.
1Canadian researchers say they have discovered the first known case of a dinosaur suffering from a deadly cancer. 2The evidence came from a fossil leg bone discovered in Alberta, Canada in 1989. The fossil was from a dinosaur called Centrosaurus. It was a four-legged plant eating animal about 6 meters long that lived between 76 and 77 million years ago. 3Examinations of the fossil showed the lower leg bone, called the fibula, was badly malformed. The scientists thought this was likely caused during the healing process of a broken leg. 4But new studies of the fossil led researchers to believe the malformation was probably caused by an aggressive bone cancer called osteosarcoma. The research team included medical professionals who study and diagnose cancers in humans. 5The findings were recently reported in the medical publication Lancet Oncology. 6The publication describes osteosarcoma as a severe and deadly bone cancer "with a worldwide incidence of 3.4 cases per million people per year." The cancer often takes the form of a disorganized bone growth that generally strikes children or young adults. The cancer can spread through bones and to other organs. 7The researchers said the latest examinations of the fossil showed the dinosaur leg bone contained "a massive...tumor." 8They said they were able to confirm that the growth was a tumor by using computed tomography, or CT, images. CT technology uses X-rays and a computer to make detailed pictures of bones, organs and tissue inside the body. 9The team compared a normal Centrosaurus fibula to the malformed one. They also compared the malformed dinosaur bone to a human fibula with a confirmed case of osteosarcoma. The comparisons led the researchers to confirm a likely case of osteosarcoma. 10Experts say since most tumors form in soft tissue that does not easily fossilize, there is little evidence of cancer in the fossil record. 11One of the project leaders was David Evans of the Royal Ontario Museum in Toronto. He spoke to Reuters news agency about the finding. He said one of the strongest pieces of evidence was that the cancer was also found in the outer layer of bone. This does not support the theory that the malformed leg was caused by a healed break. 12"This remarkable find shows that no matter how big or powerful some dinosaurs may seem, they were affected by many of the same diseases we see in humans and other animals today, including cancer," Evans said. 13He added that the Centrosaurus linked to the fossil "was likely weak and lamed by the cancer" before its death. Cancer, however, may not have killed the dinosaur. Evans said the fossil was found in a large collection of Centrosaurus individuals. This suggests that they all died as a group after being caught in a flood. 14Another lead researcher was Dr. Mark Crowther, a professor of medicine at McMaster University in Ontario. He said the new discovery was only made possible through the use of modern methods and an expert medical team representing several fields. 15"Here, we show the unmistakable signature of advanced bone cancer in a 76-million-year-old horned dinosaur - the first of its kind. It's very exciting," Crowther said. 16He added that the finding "speaks to the biology of cancer." This means cancer is not new and probably has been happening through time as "an expected complication in all animals." 17Evans added that while dinosaurs might be seen as mythical creatures, "they were living, breathing animals that suffered through horrible injuries and diseases." 18I'm Bryan Lynn. 19Reuters reported this story. Bryan Lynn adapted the report for VOA Learning English, with additional information from the Royal Ontario Museum and McMaster University. Mario Ritter, Jr. was the editor. 20We want to hear from you. Write to us in the Comments section, and visit our Facebook page. 21______________________________________________________________ 22Words in This Story 23fossil - n. the mineralized remains of plants or animals that lived a long time ago 24malformed - adj. not having the expected shape because of some problem affecting growth or development 25tumor - n. a mass of tissue in the body that is made up of cells that are not normal 26lame - adj. unable to walk normally 27signature - n. a sign that confirms something's identity 28horn - n. a hardened growth on the head of some animals such as cattle, goats and sheep 29complication - n. a health problem that arises in addition to an existing one 30mythical - adj. imaginary, something told about in stories but that is not real