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          21亿年前地球上就有能独立运动的生物了

          kira86 于2019-02-26发布 l 已有人浏览
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          科学家们发现了最古老能自主运动的生物的化石证据,证明了生物体的运动性,即生物体独立运动的能力。这一发现表明,运动能力的发展始于20多亿年前。
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          地球运动生物.jpg
          Earth's Earliest Mobile Organism Lived 2.1 Billion Years Ago

          21亿年前地球上就有能自主运动的生物了

          Scientists have discovered the oldest fossil evidence of organism motility, or the ability of an organism to move independently. The discovery shows that development of motility began more than two billion years ago.

          科学家们发现了最古老能自主运动的生物的化石证据,证明了生物体的运动性,即生物体独立运动的能力。这一发现表明,运动能力的发展始于20多亿年前。

          The fossils were found in Gabon, in rock called shale. Researchers described them as tube-like structures up to 170 millimeters long. They say the structures may have been created when the organisms moved through soft, wet dirt in search of food or a better environment.

          这些化石是在加蓬的页岩中发现的。研究人员将其描述为长达170毫米的管状结构。他们说,这些结构可能是生物在柔软?#31508;?#30340;泥?#26519;?#23547;找食物或更舒适的生存环境时形成的。

          The researchers also said the organisms might have been moving together as a group. The organisms remains a mystery as the fossils are a record only of their movement.

          研究人员还说,这些生物可能是作为一个群体在一起移动的。这些生物的本体仍然是一个谜,因为这些化石只是它们运动的记录。

          The researchers said the fossils dated back to a time when Earth was rich with oxygen. These conditions permitted simple life forms to develop more complexity.

          研究人员说,这些化石可以追溯到地球上氧气丰富的时代。这些条件下简单细胞生命体才得以进化的更为复杂。

          Life on Earth started with single-celled bacteria about 4 billion years ago. The earliest life forms could not move under their own power. The Gabon fossils dated to the Paleoproterozoic Era are about 1.5 billion years older than the previous earliest evidence of organism motility.

          地球上的生命始于大约40亿年前的单细胞细菌。最早的生命体不能靠自己的力量移动。加蓬的化石可以追溯到古元古代,比先前最早的生物活动的证据要推前15亿年。

          Abderrazak El Albani, a scientist with the University of Poitiers in France, led the team in Gabon. The shale deposit there has proven to be a treasure for the study of ancient life. Several years ago, Albani and his team discovered it held the oldest fossils know of multicellular animals.

          法国普瓦捷大学的科学家阿?#33539;?#21202;拉扎克·阿尔巴尼在加蓬领导了这一项目的研究小组。当地的页岩矿床已被证明是研究古代生命的宝库。几年前,阿尔巴尼和他的研究小组发现这里保存着已知的最古老的多细胞动物化石。

          What matters here is their astonishing complexity and diversity in shape and size, and likely in terms of metabolic, developmental and behavioral patterns, including the just-discovered earliest evidence of motility, at least for certain among them, Albani said.

          “重要的是发现它们在形状和大小上惊人的复?#26377;?#21644;多样性,也可能在代谢、发育和行为模式方面,包括刚刚发现的最早的运动性证据,至少这些发现是可以肯定的,”阿尔巴尼说。

          The first vertebrates, or animals with backbones, appeared about 525 million years ago. Dinosaurs came about 230 million years ago and human-like species developed about 300,000 years ago.

          最早的脊椎动物,或有?#26500;?#30340;动物,出现在大约5.25亿年前。恐龙大约出现在2.3亿年前,类人物种大约在30万年前形成。

          Scientists believe this early time in motility may have faced a setback soon after the Paleoproterozoic Era, about the time of the Gabon fossils. The Earth saw a considerable loss of atmospheric oxygen at that time.

          科学家们认为,这种早期的活动性可能在古元古代(大约是加蓬化石的年代)之后不久就开始减退。那时地球上的大气中氧气大量流失。

          The research was published in the Proceedings of the National Academy of Sciences.

          这项研究发表在《美国国家科学院院刊》上。

          I'm Pete Musto.

          皮特·马斯托为您播报。

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