The fo" />
頭牌英語網
投稿 圖站地圖 欄目RSS 情感美文
財經資訊時事熱點社會生活文化教育科學技術體育資訊
首頁 > 英語資訊 > 文化教育 >Extinction hits 'whole families' 物種滅絕涉及到“整個家族”

文化教育廣告

Extinction hits 'whole families' 物種滅絕涉及到“整個家族”

[文化教育]      來源:

Whole "chunks of life" are lost in extinction events, as related species vanish together, say scientists.

科學家發現,整個“生命的盒子”消失于物種滅絕事件之中,相關聯的物種全部一起消失了。

The fossil record of marine bivalves dates back to the Jurassic period
The fossil record of marine bivalves dates back to the Jurassic period

A study in the journal Science shows that extinctions tend to "cluster(聚合,成串)" on evolutionary lineages(家系,血統) - wiping out species with a common ancestor.

The finding is based on an examination of past extinctions, but could help current conservation efforts.

Researchers say that this phenomenon can result in the loss of an entire branch of the "tree of life".

The message for modern conservation, say the authors, is that some groups are more vulnerable to(易受……的攻擊) extinction than others, and the focus should be on the lineages most at risk.

Lead researcher Kaustuv Roy, a biologist from the University of California, San Diego, focused on marine(海的) bivalves(雙殼類,蚌類) - including clams(蛤), oysters(蚌) and mussels(雙殼類). The fossil record for these creatures dates back almost 200 million years.

By tracing this documented timeline of evolution and extinction, the team was able to see the effects of "background extinctions" as well as the mass extinctions, such as the one around 65 million years ago during which the dinosaurs finally died out.

Many species have become extinct during the relatively stable periods between those global calamities.

But even during such quiet periods, the team found that extinctions tended to cluster into evolutionary families - with closely-related species of clams vanishing together more often than would be predicted by chance.

Richard GREnyer, a biologist from Imperial College London, who was not involved in the study, told BBC News that by going "way back into the fossil record" this study provided important evidence of the patterns of extinction.

"Big groups of organisms tend to be similar to one another," he explained. "Look at the large cats for example."

But genetic similarities also mean, said Dr GREnyer, that "a bad effect that affects one of them, will likely affect all of them".

"It's like a casino(娛樂場) of extinctions, with the odds rigged against certain groups."

Life's library

According to this pattern, the study's authors point out, extinctions are likely to eliminate entire branches of the evolutionary tree.

Professor Roy said: "If you have whole lineages more vulnerable than others, then very soon, even with relatively moderate levels of extinction, you start to lose a lot of evolutionary history."

Julie Lockwood, an ecologist from Rutgers University in New Jersey, US, who did not take part in this study, explained that because extinction events "hit certain lineages extremely hard... we lose whole chunks of life."

"There are examples of modern species where the same thing is happening," she told BBC News.

"In seabirds for example, the same drivers - climatic change and habitat(產地,棲息地) loss - are threatening whole groups of species."

Richard GREyner likened this loss to a fire in a library.

"Because whole sections are lost - the whole of the physics section, or all of the romantic fiction, the overall loss is much worse than if you randomly burned every 400th book."

But Dr GREnyer said that this evidence could help to drive more focused, and therefore more effective conservation efforts.

"We can use this information," he said.

"It doesn't make the conservation of individual species any easier, but if we know the sorts of things that affect tigers, we can infer(推論,推斷) conservation biology about the tiger's close relatives."


Extinction hits 'whole families' 物種滅絕涉及到“整個家族”文章來源頭牌英語[文化教育]
版權聲明:頭牌英語站內內容由會員投稿或收集整理自網絡,如非特別聲明版權歸原作者與本站共同所有,轉載請注明出處。Extinction hits 'whole families' 物種滅絕涉及到“整個家族”發布在[文化教育]分類。 頭牌英語網始于2007年,主體內容由無數網友共同努力建成。如果您有優秀的英語文章或英語資料歡迎向本站投稿.
Ang Lee wins second
Down-to-earth at 10t
埃塞俄比亞兒童的死亡
研究:女教師的教育方式
中國成人文盲數位列世
  • 意大利要求美國歸還古希臘青銅
  • 女性喜歡在社交網站上美化其生
  • Family feasting rings in hap
  • 俊男靚女智商高
  • Festival in Shandong feature
  • Traces of planet collision f
  • 《蝙蝠俠》獲英國電影電視藝術
  • 索尼:亞洲最有價值的品牌
  • Shaolin's enduring appeal
  • Facial expressions 'not glob
  • 單詞whatever最令人反感
  • 男士不再青睞金發美女
  • Apple schedules OS update re
  • Two new Mozart pieces perfor
  • 微軟期待Windows7的勝利
  • 《衛報》職業網站遭黑客攻擊
  • 英國發行郵票紀念《傲慢與偏見
  • 意大利發現世界最古老的猶太教
  • Michael Jackson fans will ge
  • Let's (not) talk about sex,
  • 巴西建成首個“足球博物館”
  • 美國酒保研制出狗狗飲用啤酒
  • 冠詞的用法:        
  • Chinese film showcase opens
  • 西班牙加泰羅尼亞地區可能將禁
  • Berlin "sex academy" offers
  • 知名網絡企業聯名支持網絡中立
  • 美式英語對英國兒童影響加大
  • 生物學家拍攝到馬來西亞巽達云
  • Video gamers 'older than tho
  • China in great need of senio
  • 聯合國氣候會談結束
  • Reboot for UK's 'oldest' com
  • A-ha to break up after 25 ye
  • 研究:斑馬身上條紋可防蠅
  • 奧斯維辛集中營標語物歸原主
  • 墨西哥建筑師設計300米深“摩
  • 冷水浴能緩解肌肉酸痛但可能不
  • 《紐約時報》網站推出漢語版
  • 英國橡樹遭遇致死病毒侵襲
  • Ukrainians want village name
  • Chris Brown to play Jackson
  • 蘋果手機新應用 便捷“偶遇”
  • Major Forbidden City renovat
  • 英皇家學會網上公開牛頓等名人
  • 霍金:外星生物可能存在 與其接
  • 荷蘭將廢止褻瀆神明罪
  • 奧巴馬發布農歷龍年祝福
  • 杰克遜去世一周年 收入超過十
  • Road noise link to blood pre
  • 埃及發現一座遺失的古墓
  • 夏奇拉榮膺法國文化獎
  • 要想快樂 記住美好時光
  • Time 'runs short' on climate
  • Arctic 'warmest in 2,000 yea
  • Modernized Tibetan opera eye
  • Chicago Chinese culture orga
  • 運動能降低腸癌息肉病變危險
  • 增強網絡安全 美國將實行網絡
  • 墨西哥發現眾多石器時代巖畫
  • 快乐双彩2019101期