Thunder Lizard Thursday

Thunder Lizard Thursday: Ankylosaurus!

Ankylosaurus

Okay, I admit I got a little ¬†cartoony on this one, but it was hard to resist. ūüôā

Ankylosaurus (meaning ‚ÄúFused reptile‚ÄĚ) was the last and largest of the armoured dinosaurs.¬† Its body was protected with¬†bony plates, with¬†additional horn-like coverings. Low-slung and wider¬†than they were tall, the various species of Ankylosaurs were like tanks.
An¬†¬†Ankylosaurus’ 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. At the end of the tail, a series of plates were fused together and held aloft by tail vertebra fused together, making a massive 50kg bony club¬†¬†which at full swing could smash the skulls of even the most ferocious carnivores. Other theories about the tail club suggest that it¬†may have been used for combat between two Ankylosaurus, and ¬†display purposes for attracting mates.

 

 

Thunder Lizard Thursday: Carnotaurus and Osteoderms!

Carnotaurus 1

Carnotaurus–my favorite dinosaur besides Styracosaurus, and the only known dino predator with substantial horns!
I will be writing about Carnotaurus (“meat-eating bull”) a lot in this blog. The first thing I will cover about this gorgeous beast is its skin. Why? Because specimens of Carnotaurus¬†have given us¬†detailed impressions of the skin, including the face.

These impressions of Carnotaurus show that its hide¬†was made of many low,round¬†scales with larger, semi-conical,bony scales, called osteoderms, in rows along its sides. ¬†The word osteoderm literally means ‚Äúskin bone‚ÄĚ. Like the skin of all known dinosaurs, these scales did not overlap like scales on some lizards and snakes.

 

Thunder Lizard Thursday: Avaceratops!

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Avaceratops was just a little guy, barely as tall as a human.

Like most ceratopsians,Avaceratops had a neck frill. However, unlike most of its¬†kind, the neck frill was solid, with no openings (fenestrae). The lack of fenestrae is in fact a feature also found in Triceratops, and¬†it may represent the ancestral form of Triceratops as well as possibly being a juvenile. This could possibly explain¬†the specimen’s small body size and relatively small horns and neck frill.

 

The name Avaceratops is derived from Ava Cole. She was the wife of Eddie Cole, who found the first fossil remains in‭ ‬1981.

Thunder Lizard Thursday: Brachiosaurus’ Neck.

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Brachiosaurus had long forelimbs that caused its back to incline. This trait is not seen in most other sauropods. The¬†neck’s exiting the¬†body in a fairly straight line(the current theory) would have resulted in it pointing upwards.¬†Debate continues on the exact angle of the neck and how flexible it was.
As I was ¬†watching Jurassic Park III last night, and wishing it would hurry up and end, I did pay a little attention to the one character I cared about other than the dinosaurs; Alan Grant. He mentioned something, while looking out of the¬†plane window,about “You can see a herd of Brachiosaurus grazing”, and I remember thinking, “Hold it, Alan.”

( then I drew the above sketch.)

I am of the team of “Brachiosaurus ate from the treetops”, which is called “browsing”. Also,¬†it had¬†close cropping teeth ¬†adapted to eat the most elevated plant material such as conifer leaves and fruit.
To maneuver around in tall forests with a very long neck would be difficult, unless the neck was held vertically or at least semi-vertically. Extremely long tails would make movement in the forest difficult for high-browsers as well, and tails could not be pointed vertically . Brachiosaurus lost its long tail over time and it became quite short.

Hopefully, Alan Grant only meant that the Brachs were simply grazing from treetops, but it is very hard for us dino enthusiasts to imagine a poor Brachiosaur struggling to lean its neck way over to graze from the ground!

Thunder Lizard Thursday: Amargasaurus!

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Ah, the amazingly cool-looking Amargasaurus(“La Amarga lizard”)! Only one skeleton is known, found in February 1984 by Guillermo Rougier during an expedition led by the famous Argentine paleontologist Jos√© Bonaparte. The skeleton is nearly complete, including a fragmentary skull(sauropod skulls are rarely found complete, if at all), making Amargasaurus one of the best-known sauropods from the Early Cretaceous.

Quite small for a sauropod, Amargasaurus owned two parallel rows of tall spines down its neck and back. While it is unclear how these spines appeared in life, scientists have put forth theories that the spines could have supported skin sails or stuck out of the body as solitary structures supporting a keratin covering. They could have been used for display, combat, or defense.

 

Thunder Lizard Thursday: Alamosaurus!

Alamosaurus,© 2015 Liz Vitale

Alamosaurus,© 2015 Liz Vitale

Remember the¬†Alamosaurus!! Why? Because¬†recent analysis has shown that it¬†may have been an even bigger dinosaur than originally estimated, possibly closer in size to its¬†more famous South American cousin, one of the¬†largest known dinosaurs,Argentinosaurus.¬†In¬†fact,¬†it looks as if¬†some of the “type fossils” used to reconstruct Alamosaurus may have come from adolescents rather than full-grown adults, meaning that this titanosaur may well have attained lengths of over 60 feet from head to tail and weights in excess of 70 or 80 tons.

Alamosaurus was a gigantic titanosaur with relatively long limbs. It is one of the few titanosaurs known to have lived in late Cretaceous North America. Contrary to popular belief, Alamosaurus is not named after the Alamo in San Antonio, Texas, or the battle that was fought there. The  original specimen was discovered in New Mexico and the name Alamosaurus comes from Ojo Alamo, the geologic formation in which it was found.

Thunder Lizard Thursday: Linhenykus!

linhenykus,© 2015 Liz Vitale

linhenykus,© 2015 Liz Vitale

In 2011, a small theropod dinosaur about two feet tall was discovered in China(the theropod dinosaur family gave rise to modern birds, and included famous names such as Tyrannosaurs  and Velociraptor). The unique feature of the little dinosaur was its arms, or near lack of them, and a single functional finger on each hand bearing a large claw, which scientists believe it used to dig for termites and other insects.
Most theropods had three fingers on each hand, except for a few such as¬†Tyrannosaurus and its famous two-fingered grip. But Linhenykus belongs to a family known as the alvarezsauroids—small, long-legged dinosaurs that had one big finger alongside two barely functional nub fingers. So far, it is¬†the first two-legged dinosaur with only one claw on each forelimb.

Linhenykus gets¬†its name from Linhe, a city near the site where fossils were first found in Mongolia,and Greek nykus, “claw”.