Ankylosaurus

Ankylosaurus (name meaning "Fused Lizard") is a genus of ankylosaurid dinosaur that originated during the Late Cretaceous period in what is now North America. The largest member of the ankylosaur family, measuring 10 meters long and weighing 7 tons, Ankylosaurus is one of the world's best-known dinosaurs, recognizable for its protective armor and the massive club at the end of its tail.

In the Series 1 finale "End of the Road," a herd of four individuals and seven juveniles, were killed from the Cretaceous-Paleogene extinction event of 65 million years ago in Montana.

Era & Discovery
The last of the tank-like armored dinosaurs, Ankylosaurus lived in the Late Cretaceous period, about 86 to 65 million years ago, and died out alongside other dinosaurs during the K/T extinction event at the end of the Cretaceous. It shared its environment with animals such as Ornithomimus, Pachycephalosaurus, Torosaurus, Triceratops, and Edmontosaurus as well as the predators that hunted it, just as Tyrannosaurus rex.

In 1906, an American Museum of Natural History expedition led by paleontologist Barnum Brown discovered the type specimen of Ankylosaurus magniventris in the Hell Creek Formation, near Gilbert Creek, Montana. Although a complete skeleton has not been discovered and several other dinosaurs are represented by more extensive fossil material, Ankylosaurus is often considered the heavly built dinosaur.

Physical Attributes
An extraordinary species of herbivorous dinosaur that specialized in defense, Ankylosaurus was the largest member of the ankylosaur family, standing about 7 feet (2.3 m) tall, measuring at approximately 33 feet (10 m) long, and weighing at 7 tons (15,000 lbs.). Although a complete skeleton has not yet been discovered and several other dinosaurs are represented by more extensive fossil material, Ankylosaurus is often considered the most heavily built dinosaur. Ankylosaurus was most well known by the distinctive knobs and plates of bone known as osteoderms, and had a large club-like tail.

Ankylosaurus evolved to withstand attacks from even giant predatory dinosaurs, such as Tyrannosaurus rex. Well protected from theropod dinosaurs, large bony plates, which probably had additional horn-like coverings, protected its flanks. They were so heavily armored that such formidable natural defenses meant that Ankylosaurs was a herbivorous dinosaur that had very limited intelligence due to its skull being heavily reinforced (as was the rest of the animal) with heavy armor, leaving little space for much of a brain at all. Therefore, it did not need any serious brainpower, and consequently, its brain was quite small, even though the skull of this dinosaur was quite big and thick - even their eyelids were hardened armor to provide better protection.

And if that wasn't enough, they had a massive, formidable bony club on the end of their tails, in which multiple vertebrae had fused together to create this club, which was a 56 – 60 kg (140 – 150 lbs.) ball made out of solid bone and would have been a devastating defensive weapon wielded against attacking predators. Analysis of Ankylosaurus brain cavity indicates the most highly developed part of its brain was devoted to its sense of smell.

Ankylosaurus was the most heavily armored animals of all time. Literately, these creatures body was like an armored box. However, much like modern rhinos, Ankylosaurus also had poor eyesight, but their senses of smell could still detect a predator. This dinosaur was well protected from large predators. Large bony plates, which probably had additional horn-like coverings, protected its flanks. Its legs were directly underneath its body, not sprawled out like a tortoise's, and when it was confronted with a predator, Ankylosaurus could move quickly enough.

The skull was thick with two pairs of sharp horns at the back of the head. Parts of the tail vertebrae were fused like the handle of a club, while the base of the tail remained flexible. However, despite their heavy armor, Ankylosaurus had one vulnerable stop: its underside.

Capabilities & Weaponry

 * Armor Body: As an ankylosaur, Ankylosaurus possessed body armor covering almost its entire body, even its eyelids. However, only its underside is vulnerable to attack.
 * Club Tail: In addition to its armor, Ankylosaurus possessed a large, bony club on the end of its tail that allowed it to strike at opposing dinosaurs, such as predators.
 * Senses: While it has poor eyesight, Ankylosaurus has an acute sense of smell.

Behavior & Traits
Ankylosaurus was also a solitary dinosaur but often lived together in pairs in dry forest/prairies of the highlands during the Cretaceous. Additionally, Anklylosaurus inhabited floodplain environments that were heavily monsoonal that had occasional rainfall, tropical storms, and forest fires. In the presence of other fellow herbivores, such as Torosaurus and Triceratops, Ankylosaurus often ate with those dinosaurs. Its bony armor weighed it down so much that it fed only on low-growing shrubbery and other vegetation that was closer to the ground. Ankylosaurus females built nests during the breeding season consisting of large branches. Their eggs are laid in these nests, but egg-thieving scavengers would still sometimes raid them.

Ankylosaurus had very little brains inside their reinforced skulls. So when faced with danger, they reacted automatically and aggressively. Ankylosaurus likely defended itself by pressing itself into the ground. When carnivores attacked, it would either do that or use his clubbed tail to hit any predators. Due to its heavily-reenforced armored skull having little room for the brain, it would most likely have been reduced to instinctive reactions. Despite its small brain size, Ankylosaurus may have been able to learn from experience and that made a rather unpredictable and aggressive dinosaur.

Journal Entry
"A slow-moving, heavily-armored dinosaur of Late Cretaceous North America, Ankylosaurus ("Fused Lizard") is a large, quadrupedal herbivore built like a tank whose squat build and club-like tail make it instantly recognizable.

Measuring 33 feet long and weighing 6300 kilograms, it was the largest of the ankylosaurs with thick osteoderms covering the top half of its body, this herbivore was not an easy meal for carnivores. Predators trying their luck with this walking fortress struck at its soft underbelly.

Ankylosaurus' heavily armored back plates protect it from most attacks and her club tail acts as an effective melee weapon in defense. However, getting up close risked being hit by their massive tail club. Not only do these creatures have a tough covering of armor, but the fused bone structure on the tip of the tail is also a uniquely devastating weapon.

This club, over 18 inches across and 150 pounds in weight, is supported by ossified tendons that stiffen the tail’s end, helping it absorb impact. When swung with force, this can easily bring down apex predators. One good swing could spell doom for almost any predator."

- Allen, about Ankylosaurus in his journal

Trivia

 * Ankylosaurus is the last and largest member of its family.
 * The sound effects of Ankylosaurus are that of boar, moose, rhinoceros, and walrus sound effects.
 * Ankylosaurus is shown to be too tall, being up to a tyrannosaurus' waist. In reality, they were only up to their knee.
 * Paleontologists and dinosaur fans alike often informally refer to Ankylosaurus as the "Battle Tank of Dinosaurs", the Bane of Tyrannosarus rex.