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2018年04月21日 00:22:37来源:兰州晨报


  • The dinosaurs were aly in decline 50 million years bee the asteroid strike that finally wiped them out, a new study suggests.近日,一项最新研究显示,在小行星撞击地球、最终导致恐龙灭绝的五千万年前,恐龙数量已经在逐步减少The new assessment adds further fuel to a debate on how dinosaurs were doing when a km-wide space rock slammed into Earth 66 million years ago.在人们争论恐龙究竟在6600万年前那个km宽的太空陨石撞击地球时做什么的时候,这项新的评估无疑为这场争论火上浇油A team suggests the creatures were in long-term decline because they could not cope with the ways Earth was changing. The study appears in PNAS journal.一个研究小组表示,由于不能适应地球的变化,恐龙在很长一段时间内数量有所下降这项研究刊登在美国科学院院刊Researchers analysed the fossil remains of dinosaurs from the point they emerged 31 million years ago up to the point they went extinct. To begin with, new species evolved at an explosive rate. But things started to slow about 0 million years ago, leading to a decline in the number of species which commences at about 0 million years ago.研究者对恐龙于.31亿年前出现直至灭绝期间的恐龙化石进行了分析最开始,新物种以爆炸性的速度出现,但1.6亿年前这个过程开始放缓,导致在1.亿年前恐龙数量开始减少Dr Manabu Sakamoto, a palaeontologist from the University of Reading, who led the research, said: ;We were not expecting this result. Even though they were wiped out ultimately by the impact of the asteroid, they were actually aly on their way out around 50 million years bee the asteroid hit.;英国雷丁大学古生物学家Manabu Sakamoto士主导这项研究,他说:“我们没料到是这样的结果尽管恐龙是由于小行星撞地球而灭绝,但在这之前,即距今约5000万年前,恐龙已经开始走向衰落”Dr Sakamoto analysis shows that the long-necked giant sauropod dinosaurs were declining the fastest, whereas theropods, the group of dinosaurs that included the iconic Tyrannosaurus rex, were in a more gradual decline.Skamoto士的分析表明,长颈巨型蜥脚类恐龙衰亡速度最快,而以雷克斯霸王龙为代表的兽角类恐龙数量下降则较为缓慢Co-author Dr Chris Venditti, an evolutionary biologist from the University of Reading, told B News:来自雷丁大学的演化生物学家、论文联合作者Chris Venditti士告诉B:;The current widesp view is that dinosaurs were reigning strong right up to the impact that hit the Earth - and it the impact that drove their final extinction,; he said. ;And while that certainly true, what we found was that they were on the decline long bee that.;“目前普遍认为恐龙在小行星撞地球前统治着地球而小行星撞击也是导致它们最终灭绝的原因”他说“这当然是事实,但我们发现它们早在那之前就已经走向衰亡”Dr Venditti believes that the dinosaurs 50 million year decline rendered them even more susceptible to the environmental catastrophe that followed the asteroid impact. ;If they were reigning strong perhaps they would have fared much better than they did,; he said.Venditti士认为,恐龙在5000万年前数量的减少导致它们更易受到小行星撞地球过后的环境大灾难影响他说:“如果它们数量再多些,可能会更好地适应这种情况”The asteroid impact is commonly thought to have paved the way mammals to take over. But the new study suggests that mammalian supremacy might have occurred eventually, without a space impact.人们普遍认为,小行星撞地球为哺乳动物的翻身铺平了道路但新的研究表明,即使小行星没有撞击地球,哺乳动物最终也会统治地球Co-author Prof Mike Benton of Bristol University, told B News: ;World climates were getting cooler all the time. Dinosaurs rely on quite warm climates and mammals are better adapted to the cold. So there might have been a switch over in any case without the asteroid impact.;论文的联合作者、布里斯托大学德Mike Benton教授告诉B:“全球气候一直在变冷,恐龙适合在温暖的气候条件下生存,而哺乳动物更好地适应了寒冷的气候,无论是否有小行星撞地球,最终哺乳动物都会取代恐龙” 39650
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  • An uninhabited island in the South Pacific is littered with the highest density of plastic waste anywhere in the world, according to a study.一项研究指出,在南太平洋一座荒芜人烟的小岛上,充斥着全球最高密度的塑料垃圾Henderson Island, part of the UK Pitcairn Islands group, has an estimated 37.7 million pieces of debris on its beaches.亨德森岛是英属皮特凯恩群岛的一部分,其海滩上的塑料垃圾预估高达3770万件The island is near the centre of an ocean current, meaning it collects much rubbish from boats and South America.这个小岛靠近一个洋流中心,来自船丢弃的废品和南美洲的塑料垃圾极易被冲至岸上The joint Australian and British study said the rubbish amounted to 671 items per square metre and a total of tonnes.由澳大利亚和英国联合开展的这项研究发现,该岛每平方米的塑料垃圾多达671件,垃圾总量达吨;A lot of the items on Henderson Island are what we wrongly refer to as disposable or single-use,; said Dr Jennifer Lavers from the University of Tasmania.澳大利亚塔斯马尼亚大学的詹妮弗·莱弗斯教授称:“亨德森岛的很多东西都被我们错误的称为垃圾或者一次性物品”The study, published in the journal Proceedings of the National Academy of Sciences, described how remote islands act as a ;sink; the world rubbish.这项发表在美国《国家科学院学报上的报告,描述了这样一个偏远的岛屿是如何变成全世界的“垃圾场”的In addition to fishing items, Henderson Island was strewn with everyday things including toothbrushes, cigarette lighters and razors.除了渔具外,亨德森岛还满是牙刷、烟头和剃须刀等日常生活用品;Land crabs are making their homes inside bottle caps, containers and jars,; Dr Lavers told the B. ;At first it looks a little bit cute, but it not. This plastic is old, it sharp, it brittle and toxic.;莱弗斯教授在接受B采访时表示:“寄居蟹都在瓶盖、箱子和罐子里安家起初你可能觉得这很可爱,事实并非如此这些塑料制品陈旧、锋利,它们易碎且有毒”The condition of the island highlighted how plastic debris has affected the environment on a global scale, Dr Lavers said.莱弗斯教授称,这个小岛的情况,突显了塑料垃圾在如何影响着全球范围内的环境;Almost every island in the world and almost every species in the ocean is now being shown to be impacted one way or another by our waste,; she said. ;There not really any one person or any one country that gets a free pass on this.;她说道:“结果显示,几乎世界上的每座小岛,海洋中的每个物种,都在被这些垃圾以某种形式影响着没有任何一个人、任何一个国家能够幸免” 51
  • It no secret that moms are the queens of multitasking but one Utah mom decided to test that skill while running a half-marathon.众所周知,妈妈们是处理多重任务的能手,但犹他州的一位母亲在跑半马赛时,决定测试下接下来的这项技能While Anna Young was running the REVEL Big Cottonwood half-marathon on Sept. 9, she knew that shed eventually have to take a break to breastfeed. Five months ago, she gave birth to her first child, a daughter.9月9日,当安娜·杨正在跑芮维尔大杨木半程马拉松赛时,她知道她最终必须稍作歇息来喂奶五个月前,她生下了她的第一个孩子,一个女儿;I had to leave really early in the morning the race,; Young told A News, adding that the runners were taken by bus up the Wasatch Mountains in Utah, to the start of the downhill course.杨在接受美国广播公司新闻网采访时表示:“为了比赛,我必须早上很早出发”她补充说道,参赛者们被巴士载到犹他州的沃萨奇山脉,这里是比赛下坡路段的开始Knowing her daughter wouldnt be able to meet her on the course to breastfeed, the mom carried a hand-held pump in her backpack. Young estimated, based on her training, that shed have to stop and pump around Mile 6.知道不能给她的女儿在跑道上哺乳,这位母亲在背包里放了一个手拿的挤奶器杨估计,根据她的训练情况,她可能必须在6英里时停下来挤奶;But when I was actually running the race, I was going a lot faster than I anticipated,; Young, 7, continued, adding that she decided to wait until Mile 8 to pump.“但当我真正的跑比赛时,实际上我跑的比我预期的要快得多”7岁的杨继续说道于是她决定等到8英里时再挤奶Instead of sitting off to the side, or under a canopy on the course, she decided to walk and pump.她并没有坐到一边或是在跑道的阴影处挤奶,而是决定边走边挤;In the moment, I just decided to keep going with the race since it had been a really good atmosphere, and I just wanted to keep going,; the mother explained.这位母亲解释道:“在那一刻,我就决定继续比赛,因为比赛的氛围很好,我想继续下去”Young also noticed a photographer on the course, but she didnt expect him to take a photo of her breastfeeding.杨还在跑道上看到一位摄影师,但她没想到他会拍下她哺乳的照片;I was just really surprised and I just thought it was kind of a neat photo.;“我只是很惊讶我认为这张照片好极了” 68855
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