5億多年前動(dòng)物已有活動(dòng)能力

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Geology：5億多年前動(dòng)物已有活動(dòng)能力動(dòng)物究竟從什么時(shí)候開(kāi)始具有活動(dòng)能力？英國(guó)和加拿大的研究人員日前報(bào)告說(shuō)，他們從距今有5.65億年歷史的深?；险业搅藙?dòng)物移動(dòng)的痕跡，這可能是迄今發(fā)現(xiàn)的有關(guān)動(dòng)物移動(dòng)的最早化石證據(jù)之一。


英國(guó)牛津大學(xué)研究人員和加拿大同行在新一期美國(guó)《地質(zhì)學(xué)》（Geology）雜志上報(bào)告說(shuō)，他們?cè)趶募幽么蠹~芬蘭附近深海找到的化石上，發(fā)現(xiàn)了70余處動(dòng)物移動(dòng)的痕跡。研究人員說(shuō)，雖然還不能確認(rèn)這是什么動(dòng)物，但是這種動(dòng)物已具有通過(guò)控制肌肉來(lái)行動(dòng)的能力，它很可能像水生腔腸動(dòng)物一樣，依靠肌肉的收縮來(lái)移動(dòng)，以幫助覓食或躲避危險(xiǎn)。
研究人員說(shuō)，此前也發(fā)現(xiàn)過(guò)有關(guān)動(dòng)物具有活動(dòng)能力的化石，但這類(lèi)化石的形成年代一般都不超過(guò)距今5.6億年，一些研究人員因此認(rèn)為更古老的動(dòng)物可能都是靜止不動(dòng)的。而上述新發(fā)現(xiàn)不僅使動(dòng)物開(kāi)始具有活動(dòng)能力的時(shí)間顯著提前，而且說(shuō)明當(dāng)時(shí)的海洋生態(tài)環(huán)境比人們目前所了解的更復(fù)雜。
Biooo推薦原始出處：
Geology; February 2010; v. 38; no. 2; p. 123-126; DOI: 10.1130/G30368.1
First evidence for locomotion in the Ediacara biota from the 565 Ma Mistaken Point Formation, Newfoundland
Alexander G. Liu1, Duncan Mcllroy2 and Martin D. Brasier1,2
1 Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK
2 Department of Earth Sciences, Memorial University of Newfoundland, St. John's, Newfoundland A1B 3X5, Canada
Evidence for locomotion in the Precambrian fossil record is scant. Reliable Ediacaran trace fossils are all younger than 560 Ma, and consist of relatively simple horizontal burrows and trails from shallow-water deposits. Here we describe an assemblage of macroscopic locomotory traces from deep-water environments at Mistaken Point, southeastern Newfoundland, Canada, dated to ca. 565 Ma. These trails extend the record of complex trace fossils back into the earliest Avalonian biota. Our new evidence for large motile organisms on the seafloor at this time suggests that at least some of these early Ediacaran organisms, whose biological affinities are widely debated, could have been muscular and of metazoan grade.

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人類(lèi)在自然面前是多么的渺小啊

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自然界的很多事物是需要人類(lèi)進(jìn)一步研究和探索的！