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時間:2022-08-15 來源:本站 點擊:258次
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物种迅速进化很有可能没啥用,反倒促使他们更早灭绝******

大家一般觉得,在生物多元性的进化全过程中,很多大的进化支系是根据更快的进化发生的,他们有着更好的生物多元性;而较小的支系则经历了更迟缓的进化,他们的生物多元性更低。殊不知一项新的研究发现:进化得越来越快,绝种得也越来越快。

Rapidly evolving species more likely to go extinct, study suggests。

Researchers at the University of Bristol have found that fast evolution can lead to nowhere.。

美国布里斯托高校的科学研究工作人员最新发现,物种迅速进化很有可能促进他们更早绝种。

In a new study of lizards and their relatives, Dr Jorge Herrera-Flores of Bristol's School of Earth Sciences and colleagues have discovered that 'slow and steady wins the race'.。

布里斯托高校地球上研究院的Jorge Herrera-Flores博士以及朋友,在一项对于蛇蜥以及血亲物种的分析中发觉,“迟缓而平稳”的进化方式,使他们获得了地球上物种“进化比赛”。

The team studied lizards, snakes and their relatives, a group called the Lepidosauria. Today there are more than 10,000 species of lepidosaurs, and much of their recent success is a result of fast evolution in favourable circumstances. But this was not always the case.。

该学习工作组的研究对象是有鳞亚纲物种,包含:蛇蜥,蛇和别的血亲物种。现如今地球上有鳞亚纲物种总数做到1万多种,大家觉得该类群的取得成功进化非常大水平上是在有益地理环境下迅速进化产生的,但状况并不是一直这般。

Mr Herrera-Flores explained: "Lepidosaurs originated 250 million years ago in the early Mesozoic Era, and they split into two major groups, the squamates on the one hand, leading to modern lizards and snakes, and the rhynchocephalians on the other, represented today by a single species, the tuatara of New Zealand. We expected to find slow evolution in rhynchocephalians, and fast evolution in squamates. But we found the opposite."。

Herrera-Flores博士表述说:“有鳞亚纲物种始于2.5亿光年前三叠纪初期,他们分成两大支系,一支是有鳞类生物,慢慢演化进化成当代蛇蜥和蛇,另一支是喙头目生物,现如今仅存有单一物种——新加坡大蜥蜴。一般我们觉得喙头目生物是迟缓进化而致,有鳞类生物理应发生了迅速进化,但事实上,回答恰好反过来。”。

"We looked at the rate of change in body size among these early reptiles," said Dr Tom Stubbs, a collaborator. "We found that some groups of squamates evolved fast in the Mesozoic, especially those with specialised lifestyles like the marine mosasaurs. But rhynchocephalians were much more consistently fast-evolving."。

此项科学研究的合作方Tom Stubbs 博士说:“在科学研究了这种初期脊椎动物的身型转变速率,发觉一些有鳞类生物在三叠纪阶段进化速率迅速,尤其是这些拥有独特生活习惯的非常巨怪,比如:日常生活在深海中的沧龙。但意想不到的是,喙头目生物持续保持迅速的进化速率。”。

图中是侏罗纪晚期的蛇颈龙,它们生活在大约1.5亿年前,骨骼化石挖掘于德国南部,它是一种非凡的长体游泳喙头目生物。  图上是侏罗纪时代末期的蛇颈龙,他们生话在大概1.5亿光年前,人体骨骼动物化石发掘于法国南边,它是一种不凡的长体游水喙头目生物。

"In fact, their average rates of evolution were significantly faster than those for squamates, about twice the background rate of evolution, and we really did not expect this," said Dr Armin Elsler, another collaborator. "In the later part of the Mesozoic all the modern groups of lizards and snakes originated and began to diversify, living side-by-side with the dinosaurs, but probably not engaging with them ecologically. These early lizards were feeding on bugs, worms, and plants, but they were mainly quite small."。

“实际上,喙头目生物的均值进化速率明显超出有鳞类生物,大概是后面一种进化速率的二倍,这也是先前沒有想到的。”该科学研究的另一位合作方Armin Elsler博士说,“在三叠纪中后期,全部当代蛇蜥和蛇种都出現了,并逐渐房屋朝向多元化发展趋势,他们与霸王龙物种日常生活在一起,但很有可能在绿色生态上不容易与霸王龙产生触碰。这种远古蜥蜴以小虫子,蜘蛛和绿色植物为食,他们的身型都并不大。”。

Prof Mike Benton added: "'After the extinction of the dinosaurs, 66 million years ago, at the end of the Mesozoic, the rhynchocephalians and squamates suffered a lot, but the squamates bounced back. But for most of the Mesozoic, the rhynchocephalians were the innovators and the fast evolvers. They tailed off quite severely well before the end of the Mesozoic, and the whole dynamic changed after that."。

Mike Benton 专家教授填补道:“6600百万年三叠纪后期,恐龙的灭绝以后喙头目生物和有鳞类生物遭到了非常大严厉打击,但有鳞类生物物种迅速反跳。但就三叠纪大部分物种来讲,喙头目生物是进化颠覆性创新,处在较迅速进化情况,但在三叠纪后期该种群数量就快速走入没落,在哪以后,全部动态性就发生了转变。”。

This work confirms a challenging proposal made by the famous palaeontologist George Gaylord Simpson in his 1944 book Tempo and Mode in Evolution. He looked at the fundamental patterns of evolution in a framework of Darwinian evolution and observed that many fast-evolving species belonged to unstable groups, which were potentially adapting to rapidly changing environments.。

此项全新科学研究证明了知名的古生物学者乔冶·盖洛德·辛普森在1944年出版发行的《进化的节奏感和方式》一书里明确提出的趣味性提议。他在爱因斯坦进化论的理论框架下科学研究了物种进化的基本原则,并了解到很多迅速进化的物种归属于不稳定人群,他们能够融入迅速改变的地理环境。

蜥蜴和蛇的进化速度(蓝线)在大约2亿年的时间里远低于喙头目生物(绿线),而且它们只是在最近5000万年左右才发生了逆转。  蛇蜥和蛇的进化速率(绿线)在大概2年前的時间里远小于喙头目生物(蓝线),并且他们仅仅在近期5000萬年上下才发生了反转。

Prof Benton continued: "Slow and steady wins the race. In the classic Aesop's fable, the speedy hare loses the race, whereas the slow-moving tortoise crosses the finishing line first. Since the days of Darwin, biologists have debated whether evolution is more like the hare or the tortoise. Is it the case that big groups of many species are the result of fast evolution over a short time or slow evolution over a long time?

Benton专家教授再次讲到:“脚踏实地才可以赢得比赛。在传统的寓言故事中,跑的快的小兔子最后却输掉赛事,而跑得慢的小乌龟第一个冲过去了终点。从爱因斯坦时期逐渐,生物学者们就一直在争执最好物种进化更像小兔子或是小乌龟。有着多物种支系的物种是短期内内迅速进化的結果,或是长期迟缓进化的結果?”。

"In some cases, they can stabilise and survive well, but in many cases the species go extinct as fast as new ones emerge, and they can go extinct, just like the napping hare. On the other hand, Simpson predicted that slowly evolving species might also be slow to go extinct, and could in the end be successful in the longer term, just like the slow-moving but persistent tortoise in the fable."。

“在某种状况下,很多物种能平稳地进化发展趋势,非常好地存活出来。但在大部分状况下,物种绝种速率和新物种创造速率基本上是一样快,如同小兔子打盹的時间那麼“短暂性”。辛普森曾推测称,进化迟缓的物种很有可能也会迟缓地迈向绝种,并可以在很长一段时间内比迅速进化的物种更加取得成功,如同寓意故事中迟缓挪动但锲而不舍的小乌龟一样。”。

Boeing to expand 737******

BEIJING, Dec. 7 (Xinhua) -- Boeing and Taikoo (Shandong) Aircraft Engineering Co. Ltd. (STAECO) will expand capacity for the 737-800 Boeing Converted Freighter (BCF) in China, Boeing China announced Tuesday.。

In 2022, Boeing will add two aircraft conversion lines of 737-800BCF at STAECO's facility in Jinan, east China's Shandong Province, a new move to meet increasing demand for converted freighters, Boeing China said.。

The two new lines will begin passenger-to-freighter aircraft conversion work respectively in the first quarter and by midyear of 2022. When both new lines are operational, STAECO will have seven conversion lines focusing on the 737-800BCF.。

The 737-800BCF is a narrowbody-converted freighter model, which has received more than 200 orders and commitments from 19 customers worldwide.。

Boeing forecasts that 1,720 freighter conversions will be needed over the next 20 years. Among those, 1,200 will be narrowbody converted freighters, with 40 percent of the demand from Asian carriers. Enditem。

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Neymar to miss Argentina******

BUENOS AIRES, Nov. 15 (Xinhua) -- Brazil forward Neymar will miss his team's 2022 FIFA World Cup qualifier against Argentina because of a leg muscle injury, the Brazilian Football Confederation (CBF) said on Monday.。

The 29-year-old was ruled out of Tuesday's clash in the central-western Argentine city of San Juan after feeling pain in the adductor area of his left thigh.。

"Neymar Jr said he felt insecure about the situation and, as there is not enough time to carry out complementary exams, the technical commission decided to rest the player who will not travel with the team," a CBF statement read.。

Meanwhile, Argentina manager Lionel Scaloni confirmed that Lionel Messi would play, playing down concerns about the 34-year-old's fitness.。

The Paris Saint-Germain forward made a 14-minute cameo appearance off the bench in Argentina's 1-0 win over Uruguay on Friday, having missed Paris Saint-Germain's last two games because of knee and hamstring problems.。

"He was physically fit the other day and in the end we decided that the best thing was for him to play a few minutes so that he could get a feel for it and he is confirmed to play tomorrow," Scaloni told reporters.。

Brazil head the 10-team South American zone standings with 34 points from 12 matches, six points ahead of second-placed Argentina.。

The Selecao secured their place at next year's World Cup in Qatar with a 1-0 win over Colombia in Sao Paulo on Thursday.。

The top four teams in the group will automatically qualify for football's showpiece tournament while the fifth-ranked side while advance to an inter-continental playoff. Enditem。

男子划伤停自家门前轿车泄愤 被阎良警方刑拘******

  近期,西安公安阎良分局依法将涉嫌故意损坏财物的韩某(男,37岁,阎良区人)刑事拘留。

\

  事情还要从今年5月8日说起,当天公安阎良分局武屯派出所接到报警称:自己停放的小车被人故意损坏。接到报警后,值班民警立即赶往现场,经过调取监控发现,5月7日12时许,韩某随手捡起路边的小石子,将两辆小车划伤。韩某为何无缘无故将车辆划伤?

  经过公安机关依法传唤,到案后韩某供述,自己看见两辆小车停放在自己家门前,占用自己家门前的地方,十分生气,一时冲动,就拿起路边小石子将两辆车划了一圈。经过物价部门鉴定,两辆小车的损失约6000余元。韩某因他人在其门前停车,为发泄心中怒气,对小车进行了故意损坏,其行为已经构成了故意毁坏财物罪。“我十分后悔,不该那么冲动,触犯法律。”韩某后悔的说到。

  阎良警方提示:遇事要冷静处理,切勿冲动行事,造成严重后果将悔恨终生。如果发现别人停车,可以沟通协商或者拨打电话挪车,也可报警处理,切不可通过私自损坏他人财物来报复。

  故意毁坏财物罪,是指故意毁灭或者损坏公私财物,数额较大或者有其他严重情节的行为。根据《中华人民共和国刑法》第275条规定,故意毁坏公私财物,数额较大或者有其他严重情节的,判处3年以下有期徒刑、拘役或者罚金。故意毁坏公私财物,数额巨大或者有其他特别严重情节的,判处3年以上7年以下有期徒刑。另外,故意毁坏他人财物还要承担民事赔偿责任。

  华商报记者 谢涛


来源:华商网-华商报

编辑:报社方正

入秋的第一件外套就选它 百搭又高级

1.中国三大航司订购292架空客飞机后,美国波音公司果然坐不住了

2.中国创造相当于地球磁场90多万倍的磁场

3.张翰朱梓骁合体直播引热议 网友:梦回《流星雨》

4.耶路撒冷公交车遭枪击7人受伤 枪手向警方投案自首

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