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Dinosaurs extinction theories
Cretaceous paleogene extinction debate
Dinosaurs extinction theories
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Could you guess which dinosaur has a name related to a kitchen appliance? If you were thinking the Saltasaurus, then you were right! I will first tell you about Dinosaurs in general, so you get a good idea of what dinosaurs really are. Then, I will tell you about the Saltasaurus’ anatomy and about its name, as well as its classification, I will then tell you about how and where they live, including their diet. Finally, I will tell you about its behavior, and how it survives against enemies and predators.
Do you know what dinosaurs actually are, or how they came and disappeared from Earth? The word Dinosaur come from the Greek language and mean “Terrible Lizard” The term was first derived from the English Paleontologist Richard Owen in
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Pterodactyls are not considered dinosaurs, they were flying reptiles that lived at the time of the dinosaurs but by definition do not fall into the same category. The same goes for water based reptiles such as the Plesiosaurs. Some scientists believe that they are not extinct since their descendants, the birds, are still alive today. The color of dinosaurs is unknown because no one was alive at their time to witness or see the dinosaurs in action. You would think it would be logical to divide dinosaurs into herbivores (plant eaters) and carnivores (meat eaters), but paleontologists see things differently, they distinguish dinosaurs between Saurischian (lizard-hipped) and ornithischian (bird-hipped) dinosaurs. Saurischian dinosaurs include carnivorous theropods and herbivorous sauropods, while ornithischians account for the remainder of plant eaters, including hadrosaurs, ornithopods, and ceratopsians, among other dinosaur types. Oddly enough, birds evolved from “lizard-hipped”, rather than “bird-hipped” …show more content…
Some people would think that it comes from the word salt, but actually, the Saltasaurus does not relate to table salt, so as far as we know, there is no relation with the Saltasaurus and the stuff vendors put over their pretzels. The name Saltasaurus actually derives from the word Salta, the Argentinian city from where this beast’s remains were first found. The precise meaning of the name actually meant Lizard from Salta. Before the Saltasaurus came to light, most experts believed that when predators came, Sauropods simply defended themselves with their sheer size and whip-like tails. But this creature took it up a notch: Saltasaurus’ hide, surprised paleontologists found that it was chock full of thick, bony knobs. Its rank is Genus, and its higher classification was Saltasauridae. The saltasaurus was a member of the Saurischia (lizard-hipped) order of dinosaurs, which means although it was not closely related to lizards, it did have similar shaped pelvic bones. The saltasaurus weighed about 8 tons and measured about 39 feet (12 meters)
Ceratopsians and Pachycephalosaurs Around 144 million years ago, began the emergence of the Ornithischian dinosaurs during the Cretaceous period and diversified into North America and Asia. Ornithischians were classified as having a hip structure similar to that of birds, although they are not the descendants of birds. Marginocephalians, meaning "fringed heads" are a group of Ornithischians that have a distinctive skull structure, consisting of a slight shelf or bony frill on the back of the skull, a unique palate, and a short hip structure. These herbivores include two major groups: the Ceratopsians and the Pachcephalosaurians. These plant-eaters include the Ceratopsians, horned dinosaurs such as the Triceratops, Styrachosaurus, Pentaceratops, and the Protoceratops.
Underwater shark nets make us feel safer at the beach,but are we? That’s the question. Are we safe? There are lots of possibilities that the shark, with sharp like knife teeth, may outsmart us. Because of shark attacks we use nets, called shark nets. However, that doesn’t mean nets used in the past prevented shark attacks. These nets don’t only trap sharks they trap other sea creatures.
...ories of why dinosaurs went extinct abound, and as there is no theory yet to be truly confirmed as the “right one”, my theory of dinosaur cannibalism is also purely anecdotal. The discovery of the cannibalistic Majungatholus atopus in Madagascar is an important scientific find because it confirms a long-standing theory of cannibalism among certain carnivorous dinosaurs. Behavioral patterns of extinct animals are difficult to establish; however, these bones give authentication to previous unfounded beliefs about the ancient feeding practices of some dinosaurs.
Now here is some background information on the dinosaur that is causing this stir because of its heart. The dinosaur is a Thescelosaurus, which means wonderful lizard. The average length of the Thescelosaurus is three to four meters, nine to twelve feet, long with an average weight of three-hundred kilograms, or about six hundred and sixty two pounds. They lived from the Campanian age to Maastrichtian age which are the later stages of the Cretaceous period. Another distinguishing physical feature of Willo is the bird-hips that the dinosaur has instead of the lizard hip. They have primarily been found in Alberta, Saskatchewan, Colorado, Montana, South Dakota, and Wyoming. As far as their remains are concerned there is one complete skeleton, eight partial skeletons, elements, and teeth (Dinosauricon).
Dinosaurs were first believed to be cold-blooded because they were thought to be related closely to reptiles which are cold-blooded creatures. Cold-blooded animals don’t actually have “cold” blood, instead they rely on the temperature from their environment to regulate their own body temperature. They do this by taking advantage of external heat by basking in the sun, and by lying in the shade to cool down. A more correct term is “ectothermic” which means “heat from outside.” On the other hand, a warm-blooded animal creates heat internally by chemical reactions inside their body. They are able to regulate their body temperature internally instead of relying on their environment. Author of the article, “Dinosaurs: Warm or Cold Blooded?” Beverly Eschberger explains, “endothermic animals have a continually high requirement for food to fuel the heat generation. Providing they can find food their constantly-optimum body temperature means that they can stay active even when it is very cold” (par 3). Even though it was believed that dinosaurs were closely related to cold-blooded reptiles, most dinosaurs had similar behaviors of a bird which is a warm blooded animal. Believing dinosaurs were warm blooded would help explain the reason why dinosaurs were so dominant and plentiful for such a long period of time. There are many other factors that play a vital role in ...
So what killed the dinosaurs? Without having any background education in science it is hard for the general public to comprehend such matters and they rely on the knowledge of the scientists in this field. Although there has been much research on the subject nobody has come up with a conclusive answer. And we are left to read the countless articles, all having their own opinions as to the mass extinction. One such theory is that a shift in the solar system could have caused the mass destruction. According to an article published in Nature magazine,
We use dinosaurs to represent the changes in nature that have occurred throughout time. Studies found that although the “oldest rock did not show evidence of life, the progression of plant and animal life that changed in recognizable intervals, from ancient life, age of reptiles to the age of mammals” (Dino Nature Metaphor, slide 6), measured the age of the earth. When we think of dinosaurs in relation to nature, we think of that very powerful force that controls the cycle of life. Nature was able to yield such magnificent ferocious creatures that walked the earth and then take them back when they served nature’s purpose. Dinosaurs fit perfectly in nature’s constant
Dinosaurs are an extinct group of animals that thrived for 165 million years starting 230 million years ago in the Late Triassic period of the Mesozoic Era. Despite being extinct for the past 65 million years and not being able to study them in their true form, scientists have been able to estimate many different behaviors of dinosaurs. This paper will show that the close study and examination of different types of body and trace fossils, along with animal models, can be provided as evidence to estimate different types of behaviors in dinosaurs. The different types of behaviors examined below will fall into the categories of: mating; reproduction and nesting; social lives; locomotion; feeding; and fighting. To begin, a great deal of information gathered from fossils and compared to living animal models have been used to estimate mating behaviors.
There has been a debate about what happened to the dinosaurs since they were discovered. There are many thoughts of what happened to the dinosaurs, the two main theories behind the extinction are scientific and religious. Proof for both theories do exist and debates between scientists are still going on to which one really happened. It is a mystery as much for Evolutionists as it is for Creationists about the extinction of the dinosaurs. The fossil record of dinosaurs was poorly know for a long period of time. During this time period was when the dinosaurs were thought to have gone extinct. The scientific reason for their extinction was that there was a giant asteroid that caused chain reaction and wiped out the dinosaurs. Some scientists say the dinosaur’s extinction came quickly. Evolutionists say the dinosaurs went extinct 65 million years ago. Creationists say that the dinosaurs weren’t able to survive the Earth after the flood. Both of the theories have supporting evidence and that is why there is an ongoing debate over what really happened to the dinosaurs. (WGBH Educational Foundation and Clear Blue Sky Productions, Inc. et al., 2001)
...ll. This group still remained successful during the Jurassic period and had a wide geopraphic distribution. Other reptiles evolved to not only live on land, but to fly. The earliest known birds appeared during this period; Archaeoteryx being the first to be considered the intermediate between the birds and predatory dinosaurs. It is debated on whether this ancient bird could actually fly or merely glid from tree to tree. Carnosaurus, meaning “meat-eating” is another group of dinosaurs that ruled during the Jurassic. With such large herbivorous prey animals, the correlation of these large predators make sense of why they were so common. An Allosaurus was one of the most common Carnosaurs in North America. Upon finding numerous intact skeletons in fossil beds, it has been reported that the Allosaurus was superficially similar to the later evolving Tyrannosaurus rex.
The debate of whether dinosaurs were cold blooded or warm blooded has been ongoing since the beginning of the century. At the turn of the century scientists believed that dinosaurs had long limbs and were fairly slim, supporting the idea of a cold blooded reptile. Recently, however, the bone structure, number or predators to prey, and limb position have suggested a warm blooded species. In addition, the recent discovery of a fossilized dinosaur heart has supported the idea that dinosaurs were a warm blooded species. In this essay, I am going to give supporting evidence of dinosaurs being both warm and cold blooded. I will provide background information on the dinosaur that was discovered and what information it provides scientists.
The sun dried grass crunched under David’s feet as he reached the mailbox, sweat plastering his golden hair to his forehead. The rural landscape of Shark Bay is bone dry; the lingering heat wave serving as a slap in the face with the wind blowing what is left of his fields into whirlwinds of dirt. His was once a land of luscious green landscape, the soft air turned branches into wind chimes as the trees swayed. These same trees have been bleached by the heat ridden gusts carving tortured sculpture in their trunks. Some might now see this world as one of desolate wasteland but David grew up with the land, this land was a living, growing friend that he knew, loved, and cared for as much as he did his wife and children.
The most popular theory of dinosaur extinction, the asteroid theory, says that dinosaurs died out because of a single, giant asteroid. They say that the asteroid that struck the earth near the Gulf of Mexico went 43,000 mph and spanned six miles wide (Erdman). When it hit the Earth the asteroid it left an enormous crater that measured 24 miles deep and 125 miles wide (Erdman). Just the impact of the asteroid destroyed the forests and landscape of the majority of North America due to its massive shock wave (Erdman). Many species went extinct when the asteroid hit, these species include dinosaurs, ammonites (certain ocean dwelling creatures), pterosaurs, and some plant groups dinosaurs, ammonites (mollusks related to the octopus and the chambered nautilus), pterosaurs, and certain plant groups. Although devastating, the asteroid did not wipe out all of the animals on Earth, it didn’t exterminate fish, frogs, turtles, birds, mammals and croco...
Reptiles are vertebrate, or backboned animals constituting the class Reptilia and are characterized by a combination of features, none of which alone could separate all reptiles from all other animals.The characteristics of reptiles are numerous, therefore can not be explained in great detail in this report. In no special order, the characteristics of reptiles are: cold-bloodedness; the presence of lungs; direct development, without larval forms as in amphibians; a dry skin with scales but not feathers or hair; an amniote egg; internal fertilization; a three or four-chambered heart; two aortic arches (blood vessels) carrying blood from the heart to the body, unlike mammals and birds that only have one; a metanephric kidney; twelve pairs of cranial nerves; and skeletal features such as limbs with usually five clawed fingers or toes, at least two spinal bones associated with the pelvis, a single ball-and-socket connection at the head-neck joint instead of two, as in advanced amphibians and mammals, and an incomplete or complete partition along the roof of the mouth, separating the food and air passageways so that breathing can continue while food is being chewed. These and other traditional defining characteristics of reptiles have been subjected to considerable modification in recent times. The extinct flying reptiles, called pterosaurs or pterodactyls, are now thought to have been warm-blooded and covered with hair. Also, the dinosaurs are also now considered by many authorities to have been warm-blooded. The earliest known bird, archaeopteryx, is now regarded by many to have been a small dinosaur, despite its covering of feathers The extinct ancestors of the mammals, the therapsids, or mammallike reptiles, are also believed to have been warm-blooded and haired.
Studying the evolutionary history and adaption for this species is difficult and an ongoing struggle for scientists. It is classified in the order of Chondrichthyes suborder Elasmobranchii and family of Rhincodontidea. The difficulty in tracing this species evolutionary history stems from the fact that its ancestry dates back 245 million year ago to the Jurassic and Cretaceous