Part A: What are Dinosaurs?
Dinosaurs are land-dwelling reptiles that once roamed the Earth and the word comes from a Greek word that means "terrible lizard". Dinosaurs are defined by their skeleton features, particularly the way they hold the limbs. Dinosaurs limbs support them from beneath, (like a horse), while modern-day reptiles (such as crocodiles and lizards) limbs come out from the sides. Dinosaur are a diverse species ranging in different shapes and sizes and were able to survive in a variety of ecosystems (Australian Museum, 2016) (Natural History Museum, 2017) (Dinosaur Jungle, 2015).
Dinosaurs are divided into two major groups based on their hip structure, the Saurischia (lizard-hipped) and the Ornithischia (bird-hipped). In
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The skeleton consisted of Nine isolated teeth, left dentary (lower jaw), right and left upper ribs, partial right ilium, both ulnae (forearm), right forearm bone, finger bones, claws, right femur (thigh), both tibiae (shin bones), right fibula (calf bone), right ankle bone, foot bones, foot claws.
Almost all the fossils were discovered at the bottom of a Billabong near the town of Winton, Queensland. The site was known as Billabong Bonebed, where the greatest amount of dinosaur bones of the Australovenator and diamantinasaurus ever in Australia. In 1981 near Eagles Nest in southern Victoria, a dinosaur bone was discovered and immediately recognised as an ankle bone of a theropod dinosaur. It was first thought to belong to a dwarf species of Allosaurus, because of the similar features, but in 2009 it was confidently assigned as the Australovenator. The Australovenator was a 5-6m swift predator that stood about 1.6m high and unlike most theropod dinosaurs, the Australovenator had
The Orrorin tugenensis was found with thigh bones. And the Orrorin tugenensis had small teeth like the Australopithicus.
There are four main groups of reptiles, known as Crocodilians, Squamates, Tuataras, and Turtles. Crocodilians consists of large reptiles which includes alligators, crocodiles, gharials, and caimans. Squamates are lizards, snakes, and worm-lizards. A worm-lizard is a subterranean burrowing reptile that resembles an earthworm, a legless lizard. Tuataras are a group of reptiles that are lizard-like in appearance but are different from squamates because their skull isn’t jointed. Turtles are the most ancient reptiles alive today. They have changed very little since they first showed up 220 million years ago. The first turtle appeared 220 million years ago.(Laura Klappenbach)
Sedimentary rocks interpret dinosaur habitats through encased environmental structures of the past. Through sedimentary rocks, paleoecologists’ can examine the arranged formation of sedimentary structures to specify what type of environment the dinosaurs’ lived in. An example of a specific sedimentary rock structure can be seen through formed weathering and ripple marks by how wind and sand formed distinct patterns in the past layered sediment. These arrangements provide interpretations on the structure of the sediment and the habitat of encased fossils, through modern day comparisons
While a theropod “beast-footed” carnivore includes the T. Rex, the ones that likely roamed Wrangel-St.Elias National Park were considerably smaller. The researchers found evidence of a single theropod that was likely a tiny 9 cm long and 7 cm wide due to an impression of the sinusoidal shape. Several ornithopod, medium and large plant-eating dinosaurs, was identified by blunt and rounded digit impressions which are usually 22 cm long and 26 wide. It was the first evidence that dinosaurs roamed this vast region.
The elongated arm bones that support the wing evolved in the first coelurosaur, which probably looked like ornitholestes. As far as we know feathers are unique to birds, but this doesn’t mean that birds are not dinosaurs. Because birds belong to the group called dinosaurs, it follows that birds are feathered dinosaurs. The closest known evolutionary relatives of birds are some of the small carnivorous dinosaurs, such as velociraptor, ornitholestes, and deinonychus. The difference between a Tyrannosaurus Rex and Apatosaurus is that almost everything about Tyrannosaurus Rex indicates enormous power of one of the largest theropod dinosaurs that ever existed. They have a 4-foot-long jaw, 6-inch-long teeth and massive thighbones. It is the largest and most fearsome carnivore of all time. The fossil was originally arranged so that the dinosaur stood
Paleontology, or the study of fossils, was still a young science at the start of Victorian times, and the idea that fossils were the remains of species extinct for millions of years was only gradually taking hold. The term "dinosaur," meaning "terrible lizard," was coined in 1842 by the British paleontologist Richard Owen, who went on to produce the first life-size reconstructions of dinosaurs based on the evidence of their skeletons. The Victorian era saw the rise of the first great dinosaur hunters, including the legendary American rivals Othniel Charles Marsh and Edward Drinker
Brusatte did more research on this topic when he was a graduate student when his colleague Richard Butler proposed the idea of both of them together looking at the changes that dinosaurs went through during the ten to fifteen million year before they became extinct. I thought this was very interesting as a reader to see how Brusatte, someone who focuses on early life of dinosaurs and birds combine with someone like Butler who works in the more mathematical side of evolutionary trends. They were able to join forces and research about a single topic in order to discover something they both want to know about. Together they did their research by examining dinosaur diversity trends by using morphological disparity. They learned that most dinosaurs had a steady disparity and only herbivore dinosaurs like horned and duck billed had a declining
In the website http://nationalgeographic.org/media/pterodactyl-fossil/ they said quote “Pterodactyls were not dinosaurs! Dinosaurs are generally considered to walk upright, on either two legs (like T.Rex) or four legs (like stegosaurus). Pterodactyls
As birds, like mammals, are warm-blooded, they too are able to sustain their own body heat throughout the year. If dinosaurs were able to, as well, that would compose even more evidence in favor of dinosaurs sharing more traits in common with birds than with reptiles, as their given name, “terrible lizard”, would wrongly infer. Consequently, it seems that this discovery brings out a whole new set of questions as to how the dinosaurs truly ended up dying off at the end of the Mesozoic era, whether it be that their food supply dwindled or a combination of catastrophes that
Dinosaurs come in many different colors and sizes. The lifespan of a dinosaur is 75 to 300 years. Their daily life is hunting, mating, using the bathroom, and migrating. The defense mechanisms helped them repair their injuries 150 mya. The bone structures are the skull, jaws, neck bones, vertebrae, thigh, pelvis, tail, and rib bone. Dinosaur’s average speed is about 27 mph. Dinosaurs find their food by hunting, which is each other and some eat plants. They reproduce by hatching newborns from eggs. Some communicate by their horns or flickering the tip of their tails. Baryonyx stomach contents were found to contain fish scales, is an example of predator-prey relationship. Some animals that are related to dinosaurs are lizards, because of their skin texture.
Staurikosaurus is a dinosaur within the therapod group. Its name is Greek for “Southern Cross Lizard,” named after a small cross constellation visible in the southern hemisphere. It was named by Edwin H. Colbert and its species name is “pricei,” named after Colbert’s colleague, Llewellyn Ivor Price. Price discovered the dinosaur in 1936 in Southern Brazil, but it was described by Colbert in 1970. Staurikosaurus lived in the late Triassic period, roughly 225 million years ago, making it one of the earlier dinosaurs. It was relatively small, standing only 2.25 meters tall, but stretching to a long 7.5 meters from head to tail. It also only weighed about 66 pounds. While the fossil record of the Staurikosaurus is relatively incomplete, scientists
The Triassic period from 252 million to 200 million years ago, saw the rise of reptiles and the first dinosaurs, the Jurassic period , from about 200 million to 145 million years ago, ushered in birds and
There were a skull, claws, and bones that formed the sail on its back. If we take a closer look on the skull of Spinosaurus we could see that it has a small nostrils midway up the snout, which is used for breathing with the jaws submerged, this unique characteristic is similar to how the crocodiles breathe. The skeletal evidences shown the detail of a narrow hips and short thighs also paddle-like feet, which could possibly refer to a semi-aquatic life. According to those fossils evidences, a dinosaur expert Thomas Holtz who works at the department of Geology, University of Maryland believes that Spinosaurus
Second of all, the writer of the reading passage mentions that dinosaurs had legs under their body and might are able to run, and this point shows that dinosaurs were endotherms. In contrast, the lecturer challenge this idea by the opinion
First, Crichton noted that duckbilled dinosaurs were herbivores which are supported by a trace fossil found in the coal beds of the western North America that indicated footprints with plant fossils (Martin 2006). Furthermore, duckbilled dinosaurs lived in a vegetated environment that they had to consume enough food relative to their body size. Duckbilled dinosaurs had lengthened their skull and smoothed snout to obtain and process more food. The Dilophosaurus was described as two curved crests that extended from the eyes to the nose. The crest created a V shape on the head with red and black stripes on the crests (Crichton, 1990). Based on fossil evidence, the Dilophosaurus had two crests on the head, but there was no indication of the pigment of the crest. Next, the book stated that the T. rex does not bite the prey, instead, it twisted and tore the