Scientists: Ancient Fish Early Bones Found in the Human Hand
2020-03-30
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1Scientists have studied an ancient fish that, they say, shows the early origins of the bone structures found in the human hand.
2The discovery was made by researchers who examined a nearly complete fossil of a fish that lived about 380 million years ago.
3The fish, called Elpistostege watsoni, is believed to have lived in waters in what is now eastern Canada.
4The researchers say their findings provide new information about the way fish began to develop into vertebrates that could survive on land.
5The team of scientists from Australia and Canada reported their research in a study published in Nature.
6Inside the top of Elpistostege's front fins - called pectoral fins - were small bones appearing in several separate digits: an early form of fingers.
7These digits would have given the fish's fin the strength to hold its weight and to move on land.
8Richard Cloutier of Canada's Université du Québec à Rimouski is a paleontologist who helped lead the research.
9He told Reuters news agency the discovery shows clear links between the development of Elpistostege and human evolution.
10"By looking at Elpistostege, it is important to realize that we, as human beings, are coming from a long line of evolution, that every part of our body, like our fingers, has a long evolutionary history," Cloutier said.
11He added that such development was not only important for Homo sapiens - the species of human that exists today - but for all living organisms.
12The four-legged land animals that evolved from fish like Elpistostege are called tetrapods, a group that covers amphibians, reptiles, birds and mammals, including humans.
13The digits of the thousands of living species of tetrapods all share the same basic structures that scientists found in Elpistostege.
14The researchers used computerized image technology to examine the 1.6 meter-long fossil.
15The results showed upper and lower parts of a complete pectoral fin for the first time in any Elpistostege fish, the team reported.
16The process also showed the formation of wrist bones and divided digits.
17The digits were still contained within the fin, however, so they could not move independently like fingers, the researchers said.
18Elpistostege's body was similar to a crocodile and the animal lived mainly in water.
19It had a flat head, with eyes at the top and many teeth around the jaw area.
20Its body was thin, with well-developed fins.
21It is unclear whether Elpistostege sometimes moved on land.
22But the structure of its fins would have made this possible, said study co-writer John Long of Flinders University in Adelaide, Australia.
23"This finding pushes back the origin of digits in vertebrates to the fish level," Long said in a statement.
24"And tells us that the patterning for the vertebrate hand was first developed deep in evolution, just before fishes left the water."
25Elpistostege was known only from fossil parts until the complete set of bones was found in Canada's Miguasha National Park in 2010.
26I'm Bryan Lynn.
1Scientists have studied an ancient fish that, they say, shows the early origins of the bone structures found in the human hand. 2The discovery was made by researchers who examined a nearly complete fossil of a fish that lived about 380 million years ago. The fish, called Elpistostege watsoni, is believed to have lived in waters in what is now eastern Canada. 3The researchers say their findings provide new information about the way fish began to develop into vertebrates that could survive on land. The team of scientists from Australia and Canada reported their research in a study published in Nature. 4Inside the top of Elpistostege's front fins - called pectoral fins - were small bones appearing in several separate digits: an early form of fingers. These digits would have given the fish's fin the strength to hold its weight and to move on land. 5Richard Cloutier of Canada's Université du Québec à Rimouski is a paleontologist who helped lead the research. He told Reuters news agency the discovery shows clear links between the development of Elpistostege and human evolution. 6"By looking at Elpistostege, it is important to realize that we, as human beings, are coming from a long line of evolution, that every part of our body, like our fingers, has a long evolutionary history," Cloutier said. 7He added that such development was not only important for Homo sapiens - the species of human that exists today - but for all living organisms. 8The four-legged land animals that evolved from fish like Elpistostege are called tetrapods, a group that covers amphibians, reptiles, birds and mammals, including humans. The digits of the thousands of living species of tetrapods all share the same basic structures that scientists found in Elpistostege. 9The researchers used computerized image technology to examine the 1.6 meter-long fossil. The results showed upper and lower parts of a complete pectoral fin for the first time in any Elpistostege fish, the team reported. 10The process also showed the formation of wrist bones and divided digits. The digits were still contained within the fin, however, so they could not move independently like fingers, the researchers said. 11Elpistostege's body was similar to a crocodile and the animal lived mainly in water. It had a flat head, with eyes at the top and many teeth around the jaw area. Its body was thin, with well-developed fins. 12It is unclear whether Elpistostege sometimes moved on land. But the structure of its fins would have made this possible, said study co-writer John Long of Flinders University in Adelaide, Australia. 13"This finding pushes back the origin of digits in vertebrates to the fish level," Long said in a statement. "And tells us that the patterning for the vertebrate hand was first developed deep in evolution, just before fishes left the water." 14Elpistostege was known only from fossil parts until the complete set of bones was found in Canada's Miguasha National Park in 2010. 15I'm Bryan Lynn. 16Bryan Lynn wrote this story for VOA Learning English, based on reports from Reuters, Nature and Flinders University. Mario Ritter, Jr. was the editor. 17We want to hear from you. Write to us in the Comments section, and visit our Facebook page. 18________________________________________________________________ 19Words in This Story 20origin - n. where something begins or comes from 21fossil - n. part of an animal or plant from thousands of years ago, preserved in rock 22vertebrate - n. having a spine 23fin - n. a thin part that sticks out from a fish's body to help with movement 24evolution - n. the way in which living things gradually change and develop over millions of years 25species - n. a set of plants or animals in which the members have similar characteristics to each other and can breed with each other 26amphibian - n. an animal that lives both on land and in water 27pattern - n. a particular way something is done, is organized or happens 28jaw -n. the lower bone of the head where teeth grow