【新译Y宇宙】No.80 令人难以置信的恐龙化石揭示了一个令人惊讶的蹄状脚

Incredible dinosaur ‘mummy’ reveals a surprisingly hoof-like foot

Despite being known to science for more than a century, the duck-billed dinosaur Edmontosaurus continues to surprise. In 2013, paleontologists announced that some of these herbivorous dinosaurs had fleshy combs on the tops of their heads, much like a rooster’s. Now new research has uncovered another unexpected feature that experts had missed. Edmontosaurus had the reptilian equivalent of a hoof—its middle fingers connected and covered in a large nail.

尽管科学界已经知道了一个多世纪，但鸭嘴龙埃德蒙顿龙仍然令人惊讶。2013 年，古生物学家宣布，其中一些草食性恐龙的头顶有肉质的梳子，很像公鸡。现在，新的研究发现了专家们错过的另一个意想不到的特征。埃德蒙顿龙有相当于爬行动物的蹄子——它的中指相连并覆盖着一个大钉子。

Dinosaur fossils with preserved tissues such as skin are sometimes called “mummies,” and up until now “the assumption was that dinosaur mummies had to be rapidly buried,” says University of Tennessee, Knoxville paleontologist Stephanie Drumheller-Horton. Uncovered carcasses would attract scavengers that would pick away at the body, the thinking went, and exposure to the sun, wind, and rain could also contribute to the body’s breakdown. The faster a dinosaur was covered in sediment and shielded from destructive forces, researchers believed, the better the chance that some of its soft tissues would be preserved.

田纳西大学诺克斯维尔分校的古生物学家斯蒂芬妮·德拉姆赫勒-霍顿说，保存有皮肤等组织的恐龙化石有时被称为“木乃伊”，直到现在“人们都认为恐龙木乃伊必须被迅速掩埋”。裸露的尸体会吸引食腐动物，这些食腐动物会把尸体带走，这种想法认为，暴露在阳光、风和雨中也可能导致尸体分解。研究人员认为，恐龙被沉积物覆盖并免受破坏力影响的速度越快，其部分软组织被保存的机会就越大。

The bite marks suggest that scavengers opened up the dinosaur’s body wall, which could have allowed the fluids, gases, and microbes that built up during decomposition to drain away. As internal viscera were eaten or rotted away, the hadrosaur’s scaly, durable skin was then better able to dry out in the sun, forming a kind of wrapper around the bones before the animal was buried. Drumheller-Horton and colleagues note that this is why Dakota looks “deflated,” with the skin shrunk to the bones instead of positioned as it was in life.

咬痕表明，食腐动物打开了恐龙的体壁，这可能会让分解过程中积聚的液体、气体和微生物流失。随着内部内脏被吃掉或腐烂，鸭嘴龙的鳞片状、耐用的皮肤能够更好地在阳光下晒干，在动物被埋葬之前形成一种包裹骨头的包裹物。Drumheller-Horton 及其同事指出，这就是为什么达科他州看起来“瘪了”，皮肤缩小到骨头，而不是像生活中那样定位。

Paleontologists have puzzled over the preservation of dinosaur mummies for decades, and the new paper makes “a strong case” that Dakota was exposed to the elements before burial, says New York Institute of Technology paleontologist Karen Poole, who was not involved in the study. Even if it’s difficult to tell when scavengers fed on Dakota’s remains, she notes, it’s clear that the fossil represents a dinosaur that was somewhat rotted and desiccated rather than being a pristine corpse.

几十年来，古生物学家一直对恐龙木乃伊的保存感到困惑，新论文“有力地证明”达科他州在埋葬前曾暴露于这些元素中，纽约理工学院古生物学家凯伦普尔说，他没有参与这项研究。她指出，即使很难判断清道夫何时以达科他州的遗骸为食，但很明显，这块化石代表的是一种有点腐烂和干燥的恐龙，而不是一具原始尸体。

rot 腐烂

desiccated 干的

pristine 原始的

corpse 尸体