大西洋月刊:显然,这就是一只会游泳的恐龙的模样 [美国媒体]

这只恐龙的特征很奇怪,导致科学家们最初认为它可能是假的。一开始,像许多恐龙化石一样,这批化石也是从蒙古走私过来,然后相继在日本、英国、法国发现。2015年,私人收藏家把它买了下来,并与古生物学家Pascal Godefroit取得联系,了解下他对于这些样本的看法。

Apparently This Is What a Swimming Dinosaur Looks Like

显然,这就是一只会游泳的恐龙的模样



Its features are so strange that scientists originally thought it might be a fake.

这只恐龙的特征很奇怪,导致科学家们最初认为它可能是假的。

At first, the fossil was smuggled out of Mongolia, as many dinosaurs are. It found its way to Japan, then Britain, then France. In 2015, the private collector who finally bought it contacted the paleontologist Pascal Godefroit to get his opinion on the specimen.

一开始,像许多恐龙化石一样,这批化石也是从蒙古走私过来,然后相继在日本、英国、法国发现。2015年,私人收藏家把它买了下来,并与古生物学家Pascal Godefroit取得联系,了解下他对于这些样本的看法。

Godefroit’s opinion was: This is one weird dinosaur.

Godefroit的观点是:这是一种奇怪的恐龙。

The creature was clearly a small predator, much like Velociraptor. Its feet even had the distinctive sickle-shaped claws that clinked across the kitchen floor in Jurassic Park. But its long neck and tapering snout resembled those of a swan. Its arms and hands also had unusual proportions—something halfway between the grasping limbs of other raptors and the flattened flippers of modern penguins. It looked like a Velociraptor that had adapted for life in the water—that is, if it was even an actual dinosaur.

这个生物显然是一个小型捕食者,就像伶盗龙一样。在《侏罗纪公园》中的厨房地板上伶盗龙的脚甚至有独特的镰刀状爪子,这个生物也是。但是它长长的脖子和变尖的鼻口处又像天鹅一样,它的胳膊和手也有着不太寻常的比例——介于其他猛禽的四肢和现代企鹅扁平的脚蹼之间。它看起来就像一个适应了水中生活的伶盗龙,如果它真的是一只恐龙的话。

“It was so strange that we suspected that it might have been a chimera—a mix of different skeletons glued together. It wouldn’t be the first time,” says Andrea Cau from the University of Bologna, who joined Godefroit’s investigation. “We had to be sure that it was a real dinosaur and not a fake.”

“这太奇怪了,我们怀疑它可能是一种不同骨骼的组合在一起的怪物,而且这还不是第一次发现。”博洛尼亚大学的Andrea Cau称,他加入了Godefroit的调查组。“我们必须确保它是真的恐龙,而不是伪造的。”

Since most of the animal was still encased in a 15-inch block of stone, the team took it to Grenoble, and scanned it using a particle accelerator. The scans showed that the block was a solid mass that hadn’t been assembled from separate pieces. And the parts of the skull still within it were identical to those on the outside, as were the hidden arm bones. This swan-necked, duck-snouted, almost-paddle-limbed, sickle-clawed creature was assuredly weird—but it was a real dinosaur. (Cau notes that the scans are all openly available in case any other paleontologists want to check them.)

由于大部分动物仍被包裹在一个15英寸的石头里,因此小组把它带到格勒诺布尔,用粒子加速器扫描它。扫描结果显示,这块石块是一个实心物,并不是由单个的碎片拼合而成。石块内的头骨部分和外部的头骨吻合,隐藏的手臂骨也和外部的一样。这只天鹅颈、鸭鼻、像桨叶一般的四肢、镰刀状爪子的生物无疑是怪异的——但它是真正的恐龙。(Cau指出如果其他古生物学家想要查询,这些扫描结果都是公开的)

The team called the creature Halszkaraptor escuilliei. The name’s first half, pronounced “hull-shka-raptor,” honors Halszka Osmólska, a Polish paleontologist who discovered more than a dozen Mongolian dinosaurs and has at least four species named after her. The second half honors Fran?ois Escuillié, the French collector who bought the fossil, alerted Godefroit, and worked to return the poached specimen to its rightful home in Mongolia. It currently sits in Brussels and will remain there for a year or so while the team finishes studying it.

该团队称这个生物为埃氏哈兹卡盗龙,这个名字的前半部分发音为“hull-shka-raptor”,是为了向波兰古生物学家Halszka Osmólska致以敬意,他发现了十几种蒙古恐龙,并且至少有四个物种以他的名字命名。名字第二部分是向法国收藏家Fran?ois Escuillié致敬,这位收藏家买下了化石并告知了Godefroit,之后将被挖出的标本努力归还给蒙古。目前,该生物放置在布鲁塞尔,在研究团队研究完成之前估计还会放上一年左右。

Halszkaraptor is one of the theropods—a group of mostly meat-eating dinosaurs that count Tyrannosaurus and Velociraptor among their ranks. But unlike its kin, Halszkaraptor’s odd features suggest it was a strong swimmer that perhaps chased fish underwater, much like modern cormorants do. Outside of birds, “this is the first time we see that in a dinosaur,” says Cau. (Other ancient reptiles like paddle-limbed plesiosaurs and the dolphin-esque ichthyosaurs are not actually dinosaurs.)

埃氏哈兹卡盗龙是一种食肉恐龙——在食肉恐龙的群体中还有霸王龙和伶盗龙。但与同族亲戚不同的是,埃氏哈兹卡盗龙的奇怪特征表明它也许在水下还能追逐鱼类,是一名游泳健将,就像现在的鸬鹚一样。Cau指出“这是我们第一次在恐龙身上看到这种情况”。(其他远古的爬行动物,诸如蛇颈龙和海豚式的鱼龙其实并不是真正意义上的恐龙)

Like many other fish-eating specialists, Halszkaraptor had a lot of teeth in the front of its snout—more than twice the number of a typical dinosaur. “The first time I saw that, I asked my colleagues to repeat the analysis because I wasn’t convinced,” says Cau. The snout also contained branching bony chambers that would have once housed a large network of blood vessels and sensory nerves. Such features are common in modern crocodiles, giving them an exquisite sense of touch.

像其他食鱼专家一样,埃氏哈兹卡盗龙在前鼻口处也有很多牙齿——是典型恐龙的两倍多。Cau说:“当我第一次看到这点时,我不断的让我同事给我确认结果,因为实在难以置信”。埃氏哈兹卡盗龙鼻部还有分支的骨腔包含巨大的血管网和感觉神经,这种特征在现代鳄鱼中很常见,可以给鳄鱼细腻的触觉体验。

Halszkaraptor’s neck made up half its length from snout to hip, reminiscent of plesiosaurs, several groups of freshwater turtles, and birds like swans and herons—all of which use their long necks to catch fish. Halszkaraptor’s neck bones also had more side-to-side mobility than those of the average theropod. “That might be an adaptation to swimming, or it may indicate that the animal used rapid sweeping motions of the neck to capture some sort of small prey,” says Michael Habib, from the University of Southern California.

埃氏哈兹卡盗龙脖子的长度是从鼻子到臀部之间的一半,这让人想起蛇颈龙和一部分淡水龟,还有如天鹅和苍鹭这样的鸟类——这些动物都是用他们修长的脖子捕鱼。埃氏哈兹卡盗龙的颈骨也比一般的兽脚类动物更灵活,来自南加州大学的Michael Habib说:“这种变化可能是对游泳的一种适应,也可能表明埃氏哈兹卡盗龙利用脖子快速运动来捕捉小猎物。”

The arms “are the most problematic part,” says Cau, because they’re not quite like anything else. The long bones are flattened, and the fingers get progressively longer from the outside in—the opposite pattern to most theropods. They’re closest in proportion to the limbs of swimming birds like puffins, murres, and penguins. But they’re not flippers. “I prefer not to say if [Halszkaraptor] used its arms propulsively,” says Cau. “We don’t have information on the shoulder girdle, which would be important to determine if it swam like a penguin.”

Cau 说:埃氏哈兹卡盗龙的手臂是最成问题的部分,因为它不像其他身体部分,长骨被压平,手指从外向内逐渐变长——这与大多数兽脚类动物相反。它们的四肢与海雀、海鸠和企鹅等会游泳的鸟类比例最接近,但是它们没有脚蹼。Cau指出“我不想说埃氏哈兹卡盗龙是利用手臂来前进的,因为我们不知道它肩胛带部分的信息,而这对于确定它是否像企鹅一样游动很重要。”

Despite all these adaptations for swimming, Halszkaraptor’s back half is that of a typical landlubbing theropod. It had long legs, although it wasn’t well adapted for running. It had a longish tail, although one that was too thin to effectively counterbalance the exceptionally long neck. To compensate, Halszkaraptor probably stood upright, more so than other raptors, but not quite as erect as a penguin. Cau thinks it lived in an unstable environment, with cycles of freshwater and drought. Halszkaraptor evolved to cope with both worlds.

尽管所有这些变化都是对游泳的适应,埃氏哈兹卡盗龙身体的后半部分又是典型的陆地上的兽脚。它的腿很长,尽管不适合跑步。它的尾巴也很长,但是尾巴太薄,无法有效平衡异常长的脖子。为了弥补这一点,埃氏哈兹卡盗龙可能比其他猛禽更直立,但不像企鹅那么挺直。Cau认为,埃氏哈兹卡盗龙生活在一个不稳定的环境中,这个环境中有水和干旱的循环,因此造就了埃氏哈兹卡盗龙适应这个两栖世界。

Halszkaraptor is the first amphibious dinosaur that we know of—and that’s strange. With mammals, you have digging moles, gliding squirrels, flying bats, swimming otters, oceangoing dolphins, running gazelles, climbing monkeys, and swinging gibbons. Where’s that diversity of lifestyles among the dinosaurs? Until recently, it seemed that aside from birds, “nearly all dinosaurs are considered to be typical ground-living animals,” says Xing Xu, a prolific dino discoverer from the Chinese Academy of Sciences. That’s surprising, given how diverse they were, and how thoroughly they dominated the planet for hundreds and millions of years.

埃氏哈兹卡盗龙是我们所知的第一个两栖恐龙——这令人感到奇怪,哺乳动物中有挖洞的鼹鼠、滑行的松鼠、飞行的蝙蝠、游泳的水獭、远洋的海豚、奔跑的瞪羚、攀爬的猴子和摇摆的长臂猿,可是恐龙生活方式的多样性在哪里呢?直到最近,中国科学院众多恐龙的发现者徐星说,似乎除了鸟类“几乎所有的恐龙都被认为是典型的陆生动物”。考虑到它们的多样性,以及它们对于星球长达数亿年的主导控制,这实在令人惊讶。

But that view has changed in recent years, thanks to new discoveries. In 2014, scientists reimagined Spinosaurus, the sail-backed giant that menaced the cast of Jurassic Park 3, as a semiaquatic, crocodile-like fish hunter. They also revealed the complete skeleton of Deinocheirus, a “horse-headed, humpbacked dinosaur that looks like something out of a bad sci-fi movie.” A year later, Xu described Yi, a small predator which had both feathers and bat-like wings, and may have glided between trees. The year after that, another team described Limusaurus, a beaked plant eater that loses its teeth as it grows up. All of these species are theropods. And all of these differ wildly in their lifestyles, diets, physiques, and more. Halszkaraptor, the first amphibious theropod, is part of that revolution.

但近年来这种观点发生了变化,这要归功于新的发现。2014年,科学家们重新设想了一种以帆船为后盾的巨型恐龙——棘龙,这是一种半水生的、鳄鱼般的食鱼恐龙。他们还展示了恐手龙的完整骨架,这是一种“马头、驼背的恐龙,看起来像是糟糕科幻电影里出现的物种。”一年后,徐星描述了一种小型掠食动物,它有着既是羽毛又和蝙蝠一样的翅膀,可以在树木之间滑行。此后的一年里,另一个研究小组描述了泥潭龙,这是一个有喙的食草动物,它在长大后会失去牙齿。所有这些物种都是兽脚亚目,他们的生活方式、饮食、生理和其他方面与其他物种都有很大的不同。埃氏哈兹卡盗龙是第一个两栖的兽脚亚目,也是兽脚亚目进化的一部分。

“It’s exhilarating and yet almost embarrassing thinking back on how typecast these beasties were just a few short decades ago,” says Lindsay Zanno, from the North Carolina Museum of Natural Sciences. In particular, “the theropod section of the dinosaur family tree continues to be in flux as specimens like this one keep popping up.”

来自北卡罗莱纳自然科学博物馆的Lindsay Zanno说:“这令人振奋也让人感到尴尬,因为他们在几十年前就开始思考这些生物是如何被定型的。”特别是“恐龙家族中的兽脚部分仍在不断变化,像这样的标本还在不断出现。”

“There’s great potential for future dinosaur-fossil hunting,” Xu adds.

“未来恐龙化石的捕猎将会出现更多的可能性”徐星补充道。

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