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Avimimus: Avimimus (meaning "bird mimic")
was a very fast moving, lightweight, bird-like theropod dinosaur that may have had feathers. Avimimus was about 3 feet long and weighed
about 33 pounds. Avimimus had a long, toothless beak, a very short tail, and very long legs. This dinosaur has tiny ridges
running along its arms; some paleontologists think that they may have anchored feathers, although this is only speculation.
Avimimus was an advanced theropod, whose intelligence (as measured by
its relative brain to body weight, or EQ) was high among the dinosaurs. Avimimus may have been an omnivore, eating small animals,
insects, eggs, and some plant material. Avimimus walked on two long, slender legs. It was a fast, agile dinosaur, probably
running about as quickly as an ostrich, which can run up to 43 mph.
Bahariasaurus: Bahariasaurus
(meaning "oasis lizard") was a theropod dinosaur (perhaps a carnosaur) about 20-40 feet long, weighing about 4 tons. It was
a bipedal meat-eater from what is now Egypt. It was named by Stromer in 1934. The type species is B. ingens. The only
known fossil was destroyed in World War II. Bahariasaurus could attain fast speeds, and probably attacked its prey. Its arms were relatively long, although not
to exaggeration. On each arm were three nasty claws that could disebowl and slice apart prey. The powerful jaws could tear
and rip, during the feast or the assault.
Baryonyx: Baryonyx was an unusual theropod with huge 1-foot (30.5-cm) long claws on its hands, and long, narrow, crocodile-like
jaws with 96 small, serrated teeth (this is 1.5 times the number of teeth that most other theropods had). It had a small crest
on its snout. Baryonyx had a long, straight neck (unlike other theropods, who had s-shaped necks) and a long tail. 2 large
rear legs and 2 slightly smaller arms supported its low-slung body. Baryonyx was a theropod, whose intelligence (as measured by the relative brain to body weight, or EQ) was high among the dinosaurs. Baryonyx was a carnivore, a meat eater with huge claws and many small, sharp teeth in powerful, crocodile-like jaws.
It had 64 teeth in the lower jaw but only 32 teeth in the upper jaw (the upper teeth were larger than the lower teeth). Baryonyx was a large predator that ate fish. A fossilized Baryonyx was found with a
fossilized meal in its stomach; this stomach contained fish scales, fish bones, and some partially digested bones of a young
Iguanodon. So far, Baryonyx is the only known dinosaur that ate fish. It may have waded
in rivers and shallow seas to catch fish (just as some bears do). Baryonyx
may have walked on two or four muscular legs. Although the front legs shorter than the rear legs, they were not that much
shorter.
Brachiosaurus: Brachiosaurus is one
of the best-known sauropods. At the least, this giant beast towered 52 feet in to the air, at the tip of the raised
head. Unusually, the front legs are longer than the back. The long forearms pushed the shoulders up high above hip level,
creating a downward slope from front to back. All the legs were held straight under the body, holding up the immense weight
of the dinosaur. The tail itself was short compared to the rest of the dinosaur. The skull was small, with sharp teeth for stripping leaves off trees and foliage. Gastrolithssmall stones swallowed
by animals into the gutin the foregut immensely helped digestion. Holes at the top of the skull were possibly used for breathing,
creating vocal sounds, or perhaps to vent off the heat. Sheer size would have protected adult Brachiosaurs, but juveniles would be in
danger from attack. Fossil trackways show juveniles in the center of the herd of sauropods during movement.
Camarasaurus: This massive sauropod weighed up to an amazing 25 tons! Powerful legs held directly
under the body helped balance the immense weight, and a strong neck and tail could be vicious weapons against an attack, although
such defense with the neck is unlikely. Camarasaurus is mostly known for its rounded head, which was the trademark
of the monstrous fable Brontosaurus (more on that below). The skull
had air pockets, ormore accuratelyhollow chambers, which lightened the heavy weight of the skull without sacrificing strength.
Strong jaws and sharp teeth indicate it ate tough plant matter; interesting to note, though slightly off-topic: why is Camarasaurus
deemed an herbivore when its teeth closely resemble those of carnivores? Because it is a sauropod, and everyone knowssarcasm
intendedthat all sauropods were herbivorous. But since these teeth, which resemble the teeth on carnivores, are said to eat
tough plant meat, couldnt this be paralleled with carnivores: couldnt carnivores, before the Fall (after the Fall of Man and
the entrance of sin into the world animals began eating meat) have eaten plants, too? Large eyes and large nostrils indicate Camarasaurus was probably very alert. Camarasaurus
probably moved in herds, much like the other sauropods.
Camptosaurus: Camptosaurus weighed half a ton, measuring out at around 1,000 pounds; it stood five
feet tall at the hips, and paleontologists often compare Camptosaurus with a deer, declaring Camptosaurus was
the deer of the dinosaurs. It browsed on low vegetation with chisel-like teeth on the sides of its mouth for crushing tough
plants; the front of the jaw was a beak. Strong, agile back legs were designed
for speedy running. The front legs were smallersmall themselvesbut strong. They were probably used for feeding, or grabbing
around in the brush. Looking at the skeleton, paleontologists have figured out that it must have fed with its front legs on
the ground.
Caudipteryx: Caudipteryx (meaning
"tail feather") was a feathered theropod dinosaur. Caudipteryx resembled Velociraptor. Caudipteryx had feathers covering its very short arms, most of its body, and
on its short tail. The feathers ranged from downy to structured quills with shafts and veins up to 6 to 8 inches long. Its
feathers were symmetrical, which indicated that it did not fly (flightless birds have symmetrical feathers; flying birds have
asymmetrical ones). The feathers may have been used for insulation, retaining in its body heat. Caudipteryx had long legs,
very short arms, and was about the size of a turkey. It lacked the typical theropod long tail but had a short tail with a
generous fan of feathers up to 6 to 8 inches long. Its teeth were long, sharp, and had deep, bulbous roots. These teeth were
only in the front of the upper jaw, and pointed outward, giving it a buck-toothed look. It was found with gastroliths (gizzard stones) in its gut that were used to grind up its food. Caudipteryx did not fly but ran on two long legs. It was probably a swift
runner given its long legs and slight body."For the first time we have something that is unquestionably a dinosaur with unquestionable feathers, said paleontologist
Philip Currie of the Royal Tyrrell Museum of Paleontology, Drumheller, Alberta, Canada. While many may claim this to be a
missing link between dinosaurs and birds, its feathers didnt enable it to flyas would be expectedbut seemingly were there
for insulation purposes; in other words, to keep in body heat, which lends credibility to the dinosaurs being warm-blooded
and not cold-blooded.
Centrosaurus: The
skull of Centrosaurus alone was more than one meter (three ft) long, with a single forward thrust nasal horn and small
growths over each eye. Bony growths decorated the edge of its frill, and protective tongues of bone drooped over the two large
frill openings. Some specimens have been discovered with skin impressions. Like
Chasmosaurus, the frill was not solid bone; two large openingsfenestraeon either side reduced the weight considerably, and
provided edges for powerful jaw muscles to be attached. Centrosaurus may have lived in herds for protection from predators.
Ceratosaurus: Ceratosaurus
gets is name from the blunt horn at the tip of its snout. It also had a pair of brow horns, one over each eye. The function
of these horns are unknown, but several possibilities have been theorized, such as a special signaling device, a distinguishing
mark distinguishing sexes, but it wasnt large enough to have a role in offense or defense. The hands and feet both had four
digits with gruesome claws, but the fourth digit on each foot probably wasnt used when walking, and might have served a purpose
in balance while wading through muck or mud.
Coelophysis:
The best examples of skeletons were found by Edwin Colbert at Ghost Ranch, New Mexico, USA in 1947. Hundreds were found
jumbled together in what seems to have been a mass death. Paleontologists believe these Coelophysis died of thirst
at a dried up water source. The water returned as a flash flood (perhaps the Great Flood?). It buried and preserved their
bodies. Two
distinct forms of Coelophysis have been identified, robust and slender, which paleontologists believe were male and
female. From fossil evidence, paleontologists have worked out that Coelophysis' legs and feet were long and streamlined,
suggesting it was able to run at speed. It had a light frame no ribs in the back of its torso. Detailed investigations into its jaw show
that it had small teeth. It also had a double-hinged lower jaw. With this it could saw its food, although it probably ate
small animals whole. It may also have been cannibalistic, as the fossilized remains of other Coelophysis have been
found in the gut area.
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