Belgium's 'Wonderchicken' Believed to Be Ancestor of Modern Birds
2020-03-25
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1The remains of a small bird are giving scientists a rare look at early ancestors of modern birds.
2Scientists believe it may be the oldest known fossil from this group of animals.
3Researchers are calling the ancient creature "Wonderchicken."
4They say the fossil dates back to right before an asteroid hit the Earth, killing off dinosaurs and other creatures.
5The researchers released a report describing a partridge-sized bird, whose scientific name is Asteriornis maastrichtensis.
6It lived in coastal wetlands more than 66 million years ago during Earth's Cretaceous Period.
7The report appeared this month in Nature magazine.
8Daniel Field of Cambridge University was the lead author of the paper.
9He told The Associated Press that Wonderchicken is "down near the bottom of the modern-bird family tree."
10He said it had a face like that of today's chicken-like birds and a body like that of a duck.
11The fossil was discovered in Belgium.
12It appeared as a block of broken rocks with some broken leg bones.
13But imaging equipment showed the remains of the creature's head inside the rock.
14An earlier reported fossil find from Antarctica is almost as old.
15But its exact age and place on the evolutionary tree are not clear.
16Field thinks the Belgian skull is a little older.
17The leg bones let researchers estimate the creature was the size of a very small duck, weighing less than 400 grams.
18Its legs were long and thin, and it could probably fly, Field said.
19Researchers think birds developed from small feathered dinosaurs that lived about 150 million years ago.
20Many birds still had teeth until the asteroid struck some 66 million years ago, leading to the disappearance of three-fourths of Earth's plant and animal species.
21Close relatives of Wonderchicken survived this event.
22And the fossil itself shows qualities that have been suggested as helpful for its survival, Field said.
23Its legs suggest it did not live in trees, which is important since forests were thought to have been destroyed by wildfires after the asteroid.
24"It also probably paid to not be picky about what you are eating," since there wasn't much ... in the aftermath of the asteroid," said Field.
25The area around Wonderchicken's mouth shows no signs of a specialized diet, he added.
26Scientists unconnected to the research are expressing interest in the findings.
27Kevin Padian, a paleontologist at the University of California, Berkeley, said the fossil provides the best evidence yet of when and how the earliest ancestors of today's birds evolved.
28Genetic studies have suggested that those ancestors appeared tens of millions of years before Wonderchicken, he said.
29But the fossil record shows no support for that, and there is no known fossil that is clearly from this lineage that predates Wonderchicken, he added.
30Julia Clarke is a fossil-bird expert at the University of Texas at Austin.
31She said the fossil "has a lot of information that can start to add to our picture of the earliest steps" in the spread of living bird species.
32Fossils are like pictures taken by a camera, she said.
33And right now there are few records from this time period that relate to modern-day birds.
34"Any new picture is of key importance," said Clarke.
35I'm Pete Musto.
1The remains of a small bird are giving scientists a rare look at early ancestors of modern birds. Scientists believe it may be the oldest known fossil from this group of animals. 2Researchers are calling the ancient creature "Wonderchicken." They say the fossil dates back to right before an asteroid hit the Earth, killing off dinosaurs and other creatures. 3The researchers released a report describing a partridge-sized bird, whose scientific name is Asteriornis maastrichtensis. It lived in coastal wetlands more than 66 million years ago during Earth's Cretaceous Period. 4The report appeared this month in Nature magazine. 5Daniel Field of Cambridge University was the lead author of the paper. He told The Associated Press that Wonderchicken is "down near the bottom of the modern-bird family tree." He said it had a face like that of today's chicken-like birds and a body like that of a duck. 6The fossil was discovered in Belgium. It appeared as a block of broken rocks with some broken leg bones. But imaging equipment showed the remains of the creature's head inside the rock. An earlier reported fossil find from Antarctica is almost as old. But its exact age and place on the evolutionary tree are not clear. Field thinks the Belgian skull is a little older. 7The leg bones let researchers estimate the creature was the size of a very small duck, weighing less than 400 grams. Its legs were long and thin, and it could probably fly, Field said. 8Researchers think birds developed from small feathered dinosaurs that lived about 150 million years ago. Many birds still had teeth until the asteroid struck some 66 million years ago, leading to the disappearance of three-fourths of Earth's plant and animal species. 9Close relatives of Wonderchicken survived this event. And the fossil itself shows qualities that have been suggested as helpful for its survival, Field said. Its legs suggest it did not live in trees, which is important since forests were thought to have been destroyed by wildfires after the asteroid. 10"It also probably paid to not be picky about what you are eating," since there wasn't much ... in the aftermath of the asteroid," said Field. The area around Wonderchicken's mouth shows no signs of a specialized diet, he added. 11Scientists unconnected to the research are expressing interest in the findings. 12Kevin Padian, a paleontologist at the University of California, Berkeley, said the fossil provides the best evidence yet of when and how the earliest ancestors of today's birds evolved. 13Genetic studies have suggested that those ancestors appeared tens of millions of years before Wonderchicken, he said. But the fossil record shows no support for that, and there is no known fossil that is clearly from this lineage that predates Wonderchicken, he added. 14Julia Clarke is a fossil-bird expert at the University of Texas at Austin. She said the fossil "has a lot of information that can start to add to our picture of the earliest steps" in the spread of living bird species. 15Fossils are like pictures taken by a camera, she said. And right now there are few records from this time period that relate to modern-day birds. 16"Any new picture is of key importance," said Clarke. 17I'm Pete Musto. 18Pete Musto adapted this story for VOA Learning English using materials from the Associated Press and Reuters news agency. George Grow was the editor. 19We want to hear from you. Write to us in the Comments Section. 20_______________________________________________________________ 21Words in This Story 22fossil - n. something (such as a leaf, skeleton, or footprint that is from a plant or animal which lived in ancient times and that you can see in some rocks 23asteroid - n. any one of thousands of small planets that circle around the sun 24author - n. a person who has written something 25evolutionary - adj. describing the process by which changes in plants and animals happen over time 26feathered - adj. covered in any one of the light growths that make up the outer covering of the body of a bird 27teeth - n. the hard white objects inside the mouth that are used for biting and chewing 28picky - adj. very careful or too careful about choosing or accepting things 29aftermath - n. the period of time after a bad and usually destructive event 30lineage - n. the people who were in someone's family in past times 31key - adj. extremely important