在二疊紀末期,，地球上發(fā)生了一次大規(guī)模的生物滅絕事件,，導致多數(shù)生物銷聲匿跡，只留下少量的低級生物,。日前,，法國研究人員發(fā)現(xiàn)，一種名為鸚鵡螺（又稱菊石）的貝殼類軟體動物不但逃過一劫,，而且還以驚人的速度恢復了往日的生機,。
據(jù)法國國家科研中心最新公報介紹，地球上曾經(jīng)發(fā)生過幾次大規(guī)模的物種滅絕,，其中在距今約2.5億年前的二疊紀與三疊紀交界期發(fā)生的大滅絕最為嚴重,，它使得超過90%的物種消失。此前的研究認為,，生物圈用了1000萬到3000萬年的時間才恢復了滅絕前的繁榮,。
科研中心的古生物學家對大滅絕的“幸存者”之一——鸚鵡螺進行了研究。后者是一種帶有貝殼的軟體動物,，其貝殼花紋呈螺旋狀,。他們發(fā)現(xiàn)，大滅絕后,，這種生物僅用了100多萬年的時間就恢復了生機,，甚至比以前更加繁榮，當時已有860種鸚鵡螺分布在全球77個地區(qū),。
研究小組成員,、里昂大學的吉勒·埃斯卡爾蓋爾表示，鸚鵡螺的恢復幾乎沒有過渡期,，這可能是因為海洋中還存留了一些植物和動物,，能夠為它的生長提供營養(yǎng)。他認為,，鸚鵡螺的重生過程將幫助人們了解大滅絕后生物圈的恢復情況,。
相關的研究成果已經(jīng)發(fā)表在最新一期的美國《科學》雜志上,。（生物谷Bioon.com）
生物谷推薦原始出處：
Science 28 August 2009:DOI: 10.1126/science.1178325
Flourishing After the End-Permian Mass Extinction
Charles R. Marshall1 and David K. Jacobs2
Two hundred and fifty-two million years ago, the Paleozoic Era came to a cataclysmic close with the end-Permian mass extinction, when as much as 85% of readily fossilizable marine species became extinct. It took 5 million years for the biosphere to begin to recover from the event. At least this has been the conventional view. However, on page 1118 of this issue, Brayard et al. (1) show that ceratitid ammonoids (see the figure, panel A) recovered much faster than did most other marine groups, attaining considerable diversity just 1 million years after the mass extinction. Moreover, these mollusks reached a peak in their diversity at the end of the Early Triassic, when the diversity and body size of most other groups (particularly bivalves and gastropods) was still depressed (2). What do these data tell us about the post-apocalyptic world of the Early Triassic, and about the cause of the end-Permian extinction event itself?
1 Department of Invertebrate Paleontology, Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA.
2 Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
