在阿根廷发现了小型汽车大小的古代犰狳

在阿根廷发现了小型汽车大小的古代犰狳

An extraordinary discovery has been made by a farmer in Argentina who was fortunate enough to stumble across the fossil remains of four enormous Glyptodon fossils in the Vallimanca stream channel while transporting cattle. A post from the Institute of Archaeological and Palaeontological Investigations of the Pampa Quaternary (Incuapa-Conicet) details how the specimens were revealed from the earth following a drought in the area that has sapped the stream, forcing the top of a shell into the open.

阿根廷一名农民在运送牛群时，在Vallimanca河流中偶然发现了四具巨大的雕齿兽化石。Pampa第四纪考古与古生物学研究所的一篇文章详细介绍了这些标本是如何在干旱之后从地球上被发现的。

Farmer Juan de Dios Sota was taking his cows to graze when he spotted the unusual protrusion and didn’t recognize it to be the carcass of a horse or cow, which are common in the region. Upon spotting the shell, the farmer contacted the local authorities and a team of palaeontologists was sent out to recover the specimens and assess the four Glyptodons who it appears died together.

农民胡安·德·迪奥斯·索塔(Juan de Dios Sota)在带着奶牛去吃草时，发现了这个不寻常的突出物，但他没有认出这是马或牛的尸体，这在该地区很常见。发现这只贝壳后，这位农民联系了当地政府，派了一队古生物学家去找回这些标本，并对这四只雕齿兽进行评估，它们似乎是一起死去的。

Incuapa, Faculty of Social Sciences of the University of the Center of the Province of Buenos Aires and Conicet, researchers work to free the fossil remains from the Salado stream, Bolívar (Incuapa-Conicet)

The unusual discovery will hopefully allow researchers to clarify if this species exhibited sexual dimorphism as the group is believed to be two adults and two juveniles of differing sexes. “These kind of cases, in which several individuals together who died in the same circumstances, are really exceptional and undoubtedly will give us a lot of information about these enigmatic animals and will allow us to test several hypotheses that we have been driving in recent years,” said Palaeontologist on-site Ricardo Bonini, in a statement.

这一不寻常的发现有望让研究人员弄清楚，这一物种是否表现出两性的二态性，因为该物种被认为是两个不同性别的成年人和两个未成年人。“几个人在相同的情况下一起死亡，这是非常罕见的，毫无疑问，这将给我们提供很多关于这些神秘动物的信息，也将使我们能够测试我们近年来一直在推动的几个假设。”现场古生物学家里卡多·博尼尼在一份声明中说。

Glyptodons roamed in South America for more than 20 million years, and its thought they may have eventually gone extinct at the hands of early man, who may have used the shells of the dead animals as shelter during bad weather. These enormous, heavily armored relatives of armadillos are a part of the mammalian superorder Xenarthra. Like other Xenarthrans, they were herbivorous animals and as such their anatomy was adapted for protection.

雕齿兽在南美洲游荡了2000多万年，人们认为它们可能最终在早期人类手中灭绝了，早期人类可能在恶劣的天气里把死去动物的壳当作庇护所。这些巨大的、全副武装的犰狳亲戚是哺乳动物超目Xenarthra的一部分。像其他的Xenarthrans一样，它们是食草动物，因此它们的解剖结构被保护着。

Complete glyptodon fossil at the Cleveland Museum of Natural History in Cleveland, Ohio. Tim Evanson/Flickr CC-BY-SA 2.0

They had immensely tough, tortoise-like shells that protected their body, and bony deposits on the skin called osteoderms to protect the parts that protruded from their armor. Despite being the size of modern cars, their arsenal of defense mechanisms implies they were preyed upon and their most likely assailant was a group known as the Terror Birds, a family of flightless carnivorous birds. Glyptodons were confirmed as relatives to modern-day armadillos, whose name in Spanish means “little armored one”, by DNA sequencing carried out in 2016.

它们有非常坚硬的，像乌龟一样的外壳来保护它们的身体，皮肤上的骨沉积称为骨皮，用来保护它们盔甲上突出的部分。尽管它们的体型和现代汽车一样大，但它们强大的防御机制意味着它们曾被捕食，而它们最有可能的攻击者是一群被称为“恐怖鸟”的不会飞的食肉鸟类。2016年进行的DNA测序证实，雕齿兽与现代犰狳有亲缘关系，犰狳在西班牙语中的意思是“小甲铠”。