在1亿多年前，澳大利亚是独特的食肉恐龙混杂的家园。
澳洲发现鳄鼻恐龙。
由于在维多利亚州发现的一块单个的颈椎，这个大家庭又增添了一位新成员——一种长着像鳄鱼一样鼻子的奇异食肉恐龙，棘背龙。
这种独特的恐龙之前在南美洲、欧洲、非洲和亚洲都曾被发现，而在澳大利亚发现的化石与在英格兰发现的棘背龙的一种——重爪龙非常相似。
结合其他归属于霸王龙、迅猛龙和异龙的零碎骨骼化石，这具尚未被命名的棘背龙将有助于古生物学家搞清，这些不同的恐龙种系是何时到达澳大利亚的，以及这块大陆是何时与如何在8000万年前同其他大陆分离的。
在此之前，所有的南部大陆合并为一块超大陆，被称为冈瓦纳古陆。而新的发现，连同其他有关恐龙的发现——这些研究表明，澳大利亚的恐龙与它们在南美洲，而非非洲的亲戚更为相近——意味着，非洲可能是第一个分裂出去的大陆。
研究人员在6月14日出版的《生物学快报》上报告了这一研究成果。
棘背龙是兽脚亚目恐龙，生存于白垩纪。它是一种外貌怪诞的食肉恐龙，全长12米，臀部高约2.7米，重约4吨。这么个庞然大物，竟在背上扯起一张大大的帆。这张帆由一连串长长的脊柱支撑，每根脊柱都是从脊骨上直挺挺地长出来，使得这张帆完全不能收拢或折叠。科学家认为棘龙身长达到破纪录的17米，接近不少大型植食性蜥脚恐龙，远远把其他食肉恐龙甩在身后，是真正最大的陆地食肉恐龙。
生物探索推荐英文摘要：
ScienceShot: Crocodile-Snouted Dinosaur Discovered Down Under
Abstract:
More than 100 million years ago, Australia was home to a unique blend of predatory dinosaurs. The latest to be added to the mix—thanks to a single neck vertebra (pictured above) that was found in Victoria and described today in Biology Letters—is a bizarre class of crocodile-snouted carnivores called spinosaurs. These peculiar dinosaurs have previously been found in South America, Europe, Africa, and Asia, and the Australian fossil closely resembles a spinosaur known as Baryonyx from England. Combined with other fragmentary skeletons attributed to tyrannosaurs, raptors, and allosaurs, this as-yet-unnamed spinosaur may help paleontologists figure out when different dinosaur lineages arrived in Australia and, consequently, when and how the continent split from other land masses 80 million years ago. Prior to that time, all the southern continents were merged in a supercontinent known as Gondwana, and the new find—combined with other dino discoveries that indicate that Australian dinosaurs more closely resemble their counterparts in South America rather than Africa—suggests that Africa may have been the first to split off.
