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A desert in the American Southwest provides evidence of a hunt from long ago.
Scientists found footprints from a hunt involving ancient human beings and a large prehistoric1 sloth2. They discovered the footprints in what is now the White Sands National Monument in the state of New Mexico.
The discovery is extremely rare. The researchers say it could change scientists’ understanding of how ancient humans interacted with large animals. It also may show whether our ancestors were responsible for the disappearance3 of the giant ground sloth.
Footprints in footprints
The researchers found more than 100 footprints dating back between 10,000 and 15,000 years. They were found among particles of gypsum, a soft mineral, in the desert.
The prints seem to show humans following giant ground sloths4. The animals could reach the size of an elephant. Science magazine says they disappeared about 11,000 years ago, around the end of Earth’s last Ice Age. That would be about the same time the first human civilizations appeared on our planet.
The footprints show that, sometimes, the human hunters walked directly in markings left by the giant sloth. The distance between steps for a giant sloth is greater than that of a human step. Researchers say the markings show one human appeared to get very close to a sloth on tip-toe.
In places where the human footprints appear close to the sloth’s markings, the animal suddenly changes direction. The researchers found what they call "flailing5 circles," where it looks like the animal stood up on its back legs to defend itself with its front legs.
Hunting such a large animal "would have come with huge amounts of risk," said Matthew Bennett of Bournemouth University in England. He is a geology professor and the lead writer of a recent report on the discovery. The findings appear in the scientific publication Science Advances.
"You know, if you were chasing a small rabbit or something, little risk associated. But going head to head with a sloth, the chances are that you might come off badly."
With the newly discovered footprints, Bennett said "we can begin to understand how they did it." "That gives us a better understanding whether we are guilty or not" of hunting the animals to extinction7.
Martin Lockley is a paleontologist. Paleontology is the area of science concerned with fossilized remains8 of plants and animals. Lockley taught at the University of Colorado, in Denver, before his retirement9. He was not involved in the new research.
Lockley said “It is very rare if not unique to see unequivocal evidence of human interactions with large vertebrates based on tracks.
He added, “There are only a handful of ancient human footprint sites in North America, making this one of the best.”
The researchers say there are likely other footprints to be found at the White Sands National Monument.
I'm Ashley Thompson.
Words in This Story
tip-toe – n. the action of touching10 the ground only with one’s toes
associated – adj. closely connect with another person or thing
extinction – n. the act of making something die out
unique – adj. special; unusual
unequivocal – adj. very strong or clear
vertebrate – n. any of the bony pieces making up the backbone
1 prehistoric | |
adj.(有记载的)历史以前的,史前的,古老的 | |
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2 sloth | |
n.[动]树懒;懒惰,懒散 | |
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3 disappearance | |
n.消失,消散,失踪 | |
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4 sloths | |
懒散( sloth的名词复数 ); 懒惰; 树獭; (经济)停滞。 | |
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5 flailing | |
v.鞭打( flail的现在分词 );用连枷脱粒;(臂或腿)无法控制地乱动;扫雷坦克 | |
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6 risky | |
adj.有风险的,冒险的 | |
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7 extinction | |
n.熄灭,消亡,消灭,灭绝,绝种 | |
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8 remains | |
n.剩余物,残留物;遗体,遗迹 | |
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9 retirement | |
n.退休,退职 | |
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10 touching | |
adj.动人的,使人感伤的 | |
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