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Early Humans in Europe Likely Wiped Out by Cold Weather
Scientists say that an early human species that settled in what is now Europe was wiped out by a long ice age over 1 million years ago.
The scientists say Homo erectus, considered the first member of the human family tree to have moved out of Africa, was not able to survive a cold period that lasted 4,000 years. They published the research in early August in the journal Science.
Chris Stringer is an anthropologist1 at the Natural History Museum in London. He was one of the study's writers. Stringer and his co-writers say they studied fossils and stone tools found in Europe. The fossils showed a gap in the timeline of about 200,000 years.
"There was probably a complete interruption in the early human occupation of Europe," Stringer said.
The researchers say early human species likely did not know how to make warm clothing or find ways to make fire in cold places. The cold weather froze the ground and prevented them from gathering2 food and hunting animals.
The scientists used ancient organic compounds left by algae3 and pollen4 off Portugal's coast to learn about climate change over 1 million years ago. The study showed the average air temperature dropped by 4.5 degrees Celsius5.
Axel Timmermann is a climate physicist6 at Pusan National University in South Korea. He said the study shows that human occupation of Europe was not continuous but was interrupted by at least one "climate-induced extinction7."
It is not clear how many early humans died off during this cold period, the researchers said. "Probably at best in the tens of thousands in Europe," Stringer said of the population at the time.
Another study writer was Chronis Tzedakis, a physical geography teacher at University College London. He said humans probably returned to Europe about 900,000 years ago after "evolutionary8 or behavioral changes" that permitted them to survive in cold conditions.
Scientists have records of human-like species in Spain and Germany from 800,000 to 600,000 years ago. Homo sapiens are known in Africa from 300,000 years ago and may have briefly9 come to Europe more than 200,000 years ago. But the main movement of humans into Europe came only 60,000 years ago.
Words in This Story
species –n. a group of animals or plants that are similar and can produce young animals or plants : a group of related animals or plants that is smaller than a genus
wipe out –v. to eliminate completely
fossil –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
interruption –n. a situation where something stops for a period of time
algae –n. simple plants that have no leaves or stems and that grow in or near water
pollen –n. the very fine usually yellow dust that is produced by a plant and that is carried to other plants of the same kind usually by wind or insects so that the plants can produce seeds
induce –v. to cause something to happen
extinction –n. when something stops living or dies out
evolutionary –adj. having to do with the way something changes over time
behavioral –adj. having to do with the way someone or something acts
1 anthropologist | |
n.人类学家,人类学者 | |
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2 gathering | |
n.集会,聚会,聚集 | |
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3 algae | |
n.水藻,海藻 | |
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4 pollen | |
n.[植]花粉 | |
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5 Celsius | |
adj.摄氏温度计的,摄氏的 | |
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6 physicist | |
n.物理学家,研究物理学的人 | |
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7 extinction | |
n.熄灭,消亡,消灭,灭绝,绝种 | |
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8 evolutionary | |
adj.进化的;演化的,演变的;[生]进化论的 | |
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9 briefly | |
adv.简单地,简短地 | |
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