New Study Provides Evidence of Mysterious Human Species
2020-02-24
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1A new study suggests that a mysterious human species mated with our own species tens of thousands of years ago in Africa.
2Researchers say the study provides evidence that present-day West Africans can link about 2 to 19 percent of their genetic ancestry to an extinct human species.
3The study describes the species as a "ghost population."
4Scientists involved in the research estimated that mating between the two species happened about 43,000 years ago.
5Homo sapiens - the species of human that exists today - first appeared more than 300,000 years ago in Africa. The species later spread worldwide.
6Earlier genetic research has shown that our species mated with two early human species, the Neanderthals and the Denisovans.
7The species have been extinct for thousands of years, but modern human populations outside Africa still carry DNA from both.
8Scientists have discovered many fossil records relating to the Neanderthals and a few from the Denisovans.
9So far, though, very little is known about the newly identified "ghost population."
10Sriram Sankararaman is a human genetics and computer science professor at the University of California, Los Angeles.
11He led the study, which was recently published in Science Advances.
12Sankararaman told the Reuters news agency that "not much" is known about this mysterious species.
13"We don't know where this population might have lived, whether it corresponds to known fossils, and what its ultimate fate was," he added.
14Sankararaman said the extinct species likely split off about 650,000 years ago from the evolutionary line that led to Homo sapiens.
15The study used genetic data from hundreds of West Africans, including the Yoruba people of Nigeria and Benin and the Mende people of Sierra Leone.
16The researchers compared the data with DNA information from the Neanderthals and Denisovans.
17Scientists say they uncovered DNA material in the West Africans that can best be explained by ancestral interbreeding with an unknown member of the human family tree.
18Sankararaman said it is no longer necessary to consider only DNA from fossils of early human species to confirm that humans intermixed with them.
19"We can now see that such events took place by looking at our own DNA itself."
20He added that the discovery "opens a new path in understanding the complexity of human evolutionary history in Africa, where the picture hasn't been as clear."
21I'm Bryan Lynn.
1A new study suggests that a mysterious human species mated with our own species tens of thousands of years ago in Africa. 2Researchers say the study provides evidence that present-day West Africans can link about 2 to 19 percent of their genetic ancestry to an extinct human species. The study describes the species as a "ghost population." 3Scientists involved in the research estimated that mating between the two species happened about 43,000 years ago. 4Homo sapiens - the species of human that exists today - first appeared more than 300,000 years ago in Africa. The species later spread worldwide. 5Earlier genetic research has shown that our species mated with two early human species, the Neanderthals and the Denisovans. The species have been extinct for thousands of years, but modern human populations outside Africa still carry DNA from both. 6Scientists have discovered many fossil records relating to the Neanderthals and a few from the Denisovans. So far, though, very little is known about the newly identified "ghost population." 7Sriram Sankararaman is a human genetics and computer science professor at the University of California, Los Angeles. He led the study, which was recently published in Science Advances. 8Sankararaman told the Reuters news agency that "not much" is known about this mysterious species. "We don't know where this population might have lived, whether it corresponds to known fossils, and what its ultimate fate was," he added. 9Sankararaman said the extinct species likely split off about 650,000 years ago from the evolutionary line that led to Homo sapiens. 10The study used genetic data from hundreds of West Africans, including the Yoruba people of Nigeria and Benin and the Mende people of Sierra Leone. The researchers compared the data with DNA information from the Neanderthals and Denisovans. 11Scientists say they uncovered DNA material in the West Africans that can best be explained by ancestral interbreeding with an unknown member of the human family tree. 12Sankararaman said it is no longer necessary to consider only DNA from fossils of early human species to confirm that humans intermixed with them. "We can now see that such events took place by looking at our own DNA itself." 13He added that the discovery "opens a new path in understanding the complexity of human evolutionary history in Africa, where the picture hasn't been as clear." 14I'm Bryan Lynn. 15Reuters news agency reported on this story. Bryan Lynn adapted the report for VOA Learning English. Ashley Thompson was the editor. 16We want to hear from you. Write to us in the Comments section, and visit our Facebook page. 17_________________________________________________ 18Words in This Story 19extinct - adj. no longer living or existing 20ghost - n. the spirit of a dead person that can appear to living people 21fossil- n. part of an animal or plant from the past that has been preserved in rock 22correspond - v. to be the same or similar 23fate - n. what happens to a person, especially when it is something bad 24ultimate - adj. final or most important 25evolutionary - adj. gradual process of change and development