Antarctopelta

## AntarctopeltaAntarctic Shield

Possibly possesses a tail sword much like its relative, *Stegouros*

***“ The Southern Hemisphere has its own species of dinosaurs. These three are young Antarctopelta, small plant-eating dinosaurs. They're also one of this world's most heavily-armored animals. Even so, youngsters are safer together. ”***

― **David Attenborough**, *Ice Worlds*
***Antarctopelta*** (Antarctic Shield) is a genus of parankylosaurian dinosaur that lived in the Snow Hill Island Formation, James Ross Island, Antarctica, 71 - 70 million years ago, during the Maastrichtian stage of the Late Cretaceous Period.

## Paleobiology

Like other ankylosaurs, *Antarctopelta* was a stocky, herbivorous quadruped protected by armor plates embedded in the skin. Although a complete skeleton has not been found, the species is estimated to have been a medium-sized animal, 4 - 6 meters (13 - 20 feet) long and weighing 350 kilograms (770 pounds).

Originally classified as a primitive nodosaurid (being reconstructed with the appearance of one on Prehistoric Planet), with the 2021 discovery of *Stegouros* in the Dorotea Formation (75 - 72 million years old) of southern Chile, a new group of ankylosaurians was established, encompassing *Antarctopelta*, *Stegouros*, and *Kunbarrasaurus*, which lived in Australia around 105 - 100 million years ago. This clade, known as "Parankylosauria", is made up of small ankylosaurs that migrated to the Southern Hemisphere and thus evolved to be quite distinct from their ankylosaurid and nodosaurid relatives in the north. Rather than possessing a tail club, *Stegouros* had several tail osteoderms that fused in the form of a "macuahuitl", an ancient Aztec weapon with razor-sharp obsidian teeth that made it seem like a combination of a sword, a club, a saw, and a paddle. While the tail of *Antarctopelta* is yet to be found, it is likely that, much like its smaller cousin, it also had a macuahuitl-esque tail.

## Paleoecology

### Paleoenvironment

*Main: Snow Hill Island Formation*

Main: Snow Hill Island Formation

***“ In the Antarctic, ice clings to the highest mountains even in the summer months, but now, with temperatures falling, and the days shortening, the polar winter is spreading once more across the land. Animals must now prepare for its return. ”***

― **David Attenborough**, *Ice Worlds*
*Antarctopelta* lived 71 - 70 million years ago in the Snow Hill Island Formation, James Ross Island, Antarctica. During that time, Earth's climate was much warmer and more humid than today, thus, Antarctica would have had a climate similar to those of modern-day volcanic arcs supporting large, dense conifer forests, cycads, and ginkgos. Even back then, however, much like Antarctica today, the inhabitants of the island had to endure a long period of cold, dark months during the winter, and hence had to adapt to the freezing temperatures as snow and ice cover up the temperate forests of the region.

### Social Habits

***“ This far south, the plants on which they depend stop growing for months on end. As winter approaches, these juveniles spend more time resting. Sheltering together conserves heat, and therefore energy. With powerful front limbs, they can enlarge this winter den. But each time they return, they've grown a little bigger. Their den seems a little smaller, and the brotherly bond starts to wear a little thin. ”***

― **David Attenborough**, *Ice Worlds*
A trio of young Antarctopelta dinosaurs spend their early lives in close-knit groups, likely comprising siblings. However, as they gradually grow larger, the juveniles must separate from one another and embark on independent journeys. This separation is necessary due to limitations in resource sharing, as they become too large to inhabit their original rocky den together.

## Appearance

The fifth, penultimate segment of Ice Worlds takes place in Antarctica, just right when autumn is heralding the return of winter. Layers of snow and frost, once limited to just the highest of areas, begin to crawl back down to the lower regions, with the glaciers once more building up, and a river cascading down the side of a mountain slowly being claimed by the ice. In the forest, three young *Antarctopelta* prepare for winter hibernation. As they journey through the woods, one of them tries to pick some of the remaining vegetation from the roots of a tree. It is clear, however, that, in a short while, there will be little to no food, hence, the next few months would be a time of rest rather than a time of feeding. The three juveniles eventually find the small cave in which they rest in every winter. Unfortunately, this time, given their size, only two of the three ankylosaurs can fit in the cave. With his brothers making it clear that he can no longer share the den with them, the third *Antarctopelta* dejectedly sets off on his own to look for a place to rest.

***“ For every growing animal, this is a vulnerable time, a time when they need to separate and each take its first tentative steps to find a territory of its own. ”***

― **David Attenborough**, *Ice Worlds*
As his brothers sleep snugly in their den, the young *Antarctopelta* lies uncomfortably in the open, on the leaf-littered floor of the forest, with the noticeable increase in fog indicating the short time left before the cold times really close in. Unable to properly sleep, he is left with no other choice but to get up and continue the search for shelter and avoid the freezing winter.

***“ Herds of hadrosaurs are once again on the move. With little to eat, these huge herbivores return to look for food in warmer lands, leaving others to endure the freezing polar winter. ”***

― **David Attenborough**, *Ice Worlds*
The *Antarctopelta* eventually makes it to an open, stony field, coming across a herd of hadrosaurs searching for warmer areas where there is more food. One hadrosaur tries to check for food from a log, to no avail. For a moment, this individual and the *Antarctopelta* regard each other before continuing on their journey down opposite paths, the *Antarctopelta* searching for a place to rest in and wait the incoming winter out, the hadrosaurs looking for a more bountiful region that can sustain them.

***“ Finding a suitable territory can take animals far from the place where their lives began. It's a search that many will not survive. A cave, perhaps. ”***

― **David Attenborough**, *Ice Worlds*
Once more in a forest, the *Antarctopelta* makes his way down the woodland's rugged, treacherous grounds. Eventually, however, he finds himself facing down the mouth of a large cave.

***“ Even in the coldest months, the temperature in most caves hardly varies. But he is not the first to be attracted by this one. This cave glows. These are the tiny lures of fungus gnat larvae that produce light to attract their insect prey. This is the perfect place for an Antarctopelta to escape the worst winter weather. He'll be safe beneath these strange living stars, while outside, snow begins to fall. ”***

― **David Attenborough**, *Ice Worlds*
Walking down a stony slope, the *Antarctopelta* takes a good look of the large, warm cavern, its ceiling lit up by the whitish-blue glow of silky threads, the lures of fungi to attract insects for them to eat. Having found refuge from winter at last, the *Antarctopelta* makes his way to a corner of the cave and curls up to take his well-earned rest.

## References

1. ↑ 1.0 1.1 Reappraisal of an ankylosaurian dinosaur from the Upper Cretaceous of James Ross Island (Antarctica)
2. ↑ 2.0 2.1 2.2 Paul, Gregory S. (2010). *The Princeton Field Guide to Dinosaurs*. New Jersey: Princeton University Press. p. 230.