近日,，美國猶他州境內(nèi)發(fā)現(xiàn)一種恐龍新物種,，它具有強壯的腿部肌肉,?？茖W(xué)家認為這種恐龍利用強壯的腿部肌肉可以踢趕同類或者抵御掠食者,。
據(jù)國外媒體報道,，這種新恐龍的學(xué)名為“Brontomerus mcintoshi”，或被稱為“雷腿龍”,，是由一支美國和英國科學(xué)家小組發(fā)現(xiàn)的,。雷腿龍是一種屬于蜥腳類恐龍的長頸恐龍，該物種還包括梁龍和腕龍,，它們 生活在1.1億年前的白堊紀(jì)早期,。很可能它們與恐爪龍、猛禽龍等恐龍發(fā)生過激烈戰(zhàn)斗,。
研究人員在猶他州東部一處采石場發(fā)現(xiàn)兩具雷腿龍骨骼化石,，分別是成年體和幼年體。古生物學(xué)家猜測較大體形的成年體是幼年體恐龍的母親,，成年體恐 龍重量大約6噸,，相當(dāng)于體形較大的大象，體長達14米,，腿部長2米,。幼年體恐龍僅是成年體的三分之一，估計其質(zhì)量僅有200公斤,，體形相當(dāng)于矮種馬,，體長 約4.5米。目前,，這項最新研究發(fā)表在《波蘭古生物學(xué)報》期刊上,。
科學(xué)家表示，雷腿龍是蜥腳類恐龍家族中擁有最強壯腿部肌肉的成員,。倫敦大學(xué)學(xué)院地球科學(xué)系研究員泰勒(Mike Taylor)說:“雷腿龍是一種十分吸引人的恐龍,，這對于我們是一項令人興奮激動的考古發(fā)現(xiàn)。當(dāng)我們發(fā)現(xiàn)它外形奇特的臀部骨骼時,，便意識到這將是具有重大意義的一項研究,，最終研究證實它們可能是‘踢腿高手’，以此抵御掠食者，或者出現(xiàn)在兩只雄性在爭斗異性配偶時發(fā)生的戰(zhàn)斗,。”（生物谷Bioon.com）
生物谷推薦原文出處：
Acta Palaeontologica Polonica 56 (1), 2011: 75-98 doi:10.4202/app.2010.0073
A new sauropod dinosaur from the Lower Cretaceous Cedar Mountain Formation, Utah, USA
Michael P. Taylor, Mathew J. Wedel, and Richard L. Cifelli
Brontomerus mcintoshi is a new genus and species of sauropod dinosaur from the Hotel Mesa Quarry in Grand County, Utah, USA, in the upper part of the Ruby Ranch Member (Aptian–Albian) of the Lower Cretaceous Cedar Mountain Formation. It is known from at least two fragmentary specimens of different sizes. The type specimen is OMNH 66430, the left ilium of a juvenile individual; tentatively referred specimens include a crushed presacral centrum, a complete and well?preserved mid?to?posterior caudal vertebra, the partial centrum of a distal caudal vertebra, a complete pneumatic anterior dorsal rib from the right side, the nearly complete left scapula of a much larger, presumably adult, individual, and two partial sternal plates. Brontomerus is diagnosed by five autapomorphies of the type specimen: preacetabular lobe 55% of total ilium length, longer than in any other sauropod; preacetabular lobe directed anterolaterally at 30o to the sagittal, but straight in dorsal view and vertically oriented; postacetabular lobe reduced to near absence; ischiadic peduncle reduced to very low bulge; ilium proportionally taller than in any other sauropod, 52% as high as long. In a phylogenetic analysis, Brontomerus was recovered as a camarasauromorph in all most parsimonious trees, but with uncertain position within that clade. The large preacetabular lobe of the ilium anchored powerful protractor and abductor muscles, but precise interpretation is impossible without functionally related elements such as femora and proximal caudal vertebrae. Brontomerus is the eighth sauropod genus named from the Early Cretaceous of North America, and more remain to be described: North American sauropod diversity did not decline catastrophically at the end of the Jurassic as often assumed. The most striking differences between Late Jurassic and Early Cretaceous sauropod faunas in North America is that the former are abundant and dominated by diplodocids, whereas the latter are comparatively scarce—though still diverse—and dominated by macronarians.
Key words: Dinosauria, Sauropoda, Camarasauromorpha, Brontomerus, Brontomerus mcintoshi, diversity, Early Cretaceous, North America.
