Scientists: South African Fossils Tell of the Struggle to Survive
2023-05-30
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1A recent study says fossil remains of a top meat-eating animal living 250 million years ago, which had only been found in the world's northern half, also lived in South Africa.
2The scientists all have links to South Africa.
3They reported on fossils of a large ancestor to today's mammals called Inostrancevia.
4The creature had only been known from fossils found in Russia near the Artic Sea until the new fossils were discovered at a farm in central South Africa.
5The fossils suggest that Inostrancevia left its native area and moved about 12,000 kilometers over a period of hundreds or thousands of years.
6During that period, most of the world's big landmasses were connected in what scientists call Pangea.
7Inostrancevia filled the ecological place of a top meat-eating animal in South Africa that had been missing after four other species had died out.
8"However, it did not survive there long," said Christian Kammerer.
9He is a scientist with the North Carolina Museum of Natural Sciences.
10Kammerer studies fossils and was the lead writer of the research published in Current Biology.
11"They have no living descendants, but they are a member of the larger group called synapsids, which includes mammals as living representatives," Kammerer added.
12Kammerer noted that Inostrancevia and all of its closest relatives disappeared in the mass extinction called "the Great Dying."
13The event took place at the end of what Earth scientists, or geologists, call the Permian Period.
14Scientists believe that life on Earth was under pressure about 250 million years ago.
15Some scientists say volcanic activity in today's Russian area called Siberia warmed Earth temperatures.
16It caused up to 90 percent of species to die out.
17Inostrancevia is part of a group of animals called protomammals that combined reptile-like and mammal-like features.
18It was three to four meters long and had a large, long head with a set of huge teeth it used to kill and eat other animals.
19If the animals were small enough, Inostrancevia swallowed them whole.
20Inostrancevia was structured differently from both reptiles and mammals but was usual for protomammals.
21It carried itself in a way that was neither flat to the ground like reptiles nor standing tall like mammals.
22It also lacked facial muscles found in mammals and did not produce milk.
23"Whether these animals were furry or not remains an open question," Kammerer said.
24The mass extinction happened over about one million years.
25It led to the rise of dinosaurs during the following Triassic Period.
26The scientists noted that top meat-eating animals are especially affected by extinction because they require the most food and space.
27The researchers said they see similarities between the Permian mass extinction and today's climate change problem.
28Pia Viglietti is with the Field Museum in Chicago.
29She helped write the study.
30She said unlike the animals that came before us during the Permian Period,
31"we actually have the ability to do something to prevent this kind of ecosystem crisis from happening again."
32I'm Gregory Stachel.
1A recent study says fossil remains of a top meat-eating animal living 250 million years ago, which had only been found in the world's northern half, also lived in South Africa. 2The scientists all have links to South Africa. They reported on fossils of a large ancestor to today's mammals called Inostrancevia. The creature had only been known from fossils found in Russia near the Artic Sea until the new fossils were discovered at a farm in central South Africa. 3The fossils suggest that Inostrancevia left its native area and moved about 12,000 kilometers over a period of hundreds or thousands of years. During that period, most of the world's big landmasses were connected in what scientists call Pangea. 4Inostrancevia filled the ecological place of a top meat-eating animal in South Africa that had been missing after four other species had died out. 5"However, it did not survive there long," said Christian Kammerer. He is a scientist with the North Carolina Museum of Natural Sciences. Kammerer studies fossils and was the lead writer of the research published in Current Biology. 6"They have no living descendants, but they are a member of the larger group called synapsids, which includes mammals as living representatives," Kammerer added. 7Kammerer noted that Inostrancevia and all of its closest relatives disappeared in the mass extinction called "the Great Dying." The event took place at the end of what Earth scientists, or geologists, call the Permian Period. 8Scientists believe that life on Earth was under pressure about 250 million years ago. Some scientists say volcanic activity in today's Russian area called Siberia warmed Earth temperatures. It caused up to 90 percent of species to die out. 9Inostrancevia is part of a group of animals called protomammals that combined reptile-like and mammal-like features. It was three to four meters long and had a large, long head with a set of huge teeth it used to kill and eat other animals. If the animals were small enough, Inostrancevia swallowed them whole. 10Inostrancevia was structured differently from both reptiles and mammals but was usual for protomammals. It carried itself in a way that was neither flat to the ground like reptiles nor standing tall like mammals. It also lacked facial muscles found in mammals and did not produce milk. 11"Whether these animals were furry or not remains an open question," Kammerer said. 12The mass extinction happened over about one million years. It led to the rise of dinosaurs during the following Triassic Period. 13The scientists noted that top meat-eating animals are especially affected by extinction because they require the most food and space. 14The researchers said they see similarities between the Permian mass extinction and today's climate change problem. 15Pia Viglietti is with the Field Museum in Chicago. She helped write the study. She said unlike the animals that came before us during the Permian Period, "we actually have the ability to do something to prevent this kind of ecosystem crisis from happening again." 16I'm Gregory Stachel. 17Will Dunham reported this story for Reuters. Gregory Stachel adapted it for VOA Learning English. 18________________________________________________________________________ 19Words in This Story 20fossil -n. the mineralized remains of an animal or plant that lived a very long time ago 21species - n. a group of animals or plants that are similar and can produce young animals or plants 22extinction - n. the state or situation that results when something (such as a plant or animal species) has died out completely 23mammal - n. a class of animal that feeds milk to its young and that usually has hair and special ear bones 24descendant - n. a plant or animal that is related to a particular plant or animal that lived long ago 25feature - n. an important part, quality, or ability 26fur - n. the hairy coat of an animal especially when it is soft and thick 27ecosystem - n. everything that exists in a particular environment 28_______________________________________________________________________ 29What do you think of this story? 30We want to hear from you. We have a new comment system. Here is how it works: 31Each time you return to comment on the Learning English site, you can use your account and see your comments and replies to them. Our comment policy is here.