|
澳大利亚一新蜥脚类揭示白垩纪恐龙的古生物地理学 Savannasaurus elliottorum 艾氏 草原龙 （新属，新种） New Australian sauropods shed light on Cretaceous dinosaur palaeobiogeography Stephen F. Poropat , Philip D.Mannion , Paul Upchurch , Scott A. Hocknull , Benjamin P. Kear , Martin Kundrát , Travis R. Tischler, Trish Sloan , George H. K. Sinapius , Judy A. Elliot & David A. Elliott Abstract Australian dinosaurs have played arare but controversial role in the debate surrounding the effect of Gondwananbreak-up on Cretaceous dinosaur distribution. Major spatiotemporal gaps in theGondwanan Cretaceous fossil record, coupled with taxon incompleteness, havehindered research on this effect, especially in Australia. Here we report ontwo new sauropod specimens from the early Late Cretaceous of Queensland,Australia, that have important implications for Cretaceous dinosaurpalaeobiogeography. Savannasaurus elliottorum gen. et sp. nov. comprises one ofthe most complete Cretaceous sauropod skeletons ever found in Australia,whereas a new specimen of Diamantinasaurus matildae includes the first evercranial remains of an Australian sauropod. The results of a new phylogeneticanalysis, in which both Savannasaurus and Diamantinasaurus are recovered withinTitanosauria, were used as the basis for a quantitative palaeobiogeographicalanalysis of macronarian sauropods. Titanosaurs achieved a worldwidedistribution by at least 125 million years ago, suggesting that mid-CretaceousAustralian sauropods represent remnants of clades which were widespread duringthe Early Cretaceous. These lineages would have entered Australasia viadispersal from South America, presumably across Antarctica. High latitudesauropod dispersal might have been facilitated by Albian–Turonian warming thatlifted a palaeoclimatic dispersal barrier between Antarctica and South America. | 
IP卡
狗仔卡
发表于 2016-10-21 00:55:32
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
显身卡
楼主