Estimating Dinosaur Behavior 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. Display, communication, and the act of mating are estimated behaviors involved in the mating process of dinosaurs. The sexual behaviors of modern vertebrae are often used as a starting point to estimate that of dinosaurs. For instance, most modern vertebrae go through a sexual selection process as they choose their mate based on preferred traits. This is demonstrated with the modern day peacock. The visual stimulus the male provides with its tail feathers aids in the opposite gender’s sexual selection process. According to Martin, in this respect, the ceratopsians have the most obvious sexual displays in the form of ornate and broad head shields with horns, knobs, and bosses. Though these body parts could definitely prove useful to fend off potential predators, it is more likely that they were used for: visual recognition within their species; pote... ... middle of paper ... ...oceedings: Biological Sciences Vol. 274 No. 1616 (2007): 1359-1360. Web. 5 Apr. 2014. Thuldorn, Tony. “Dinosaur Tracks.” Rev. by Andrew Cohen. PALAIOS Vol. 6 No. 2 (1991): 192-193. Web. 5 Apr. 2014. Varricchio, David J., Frankie Jackson, and Clive N. Trueman. “A Nesting Trace with Eggs for the Cretaceous Theropod Dinosaur Troodon formosus.” Journal of Vertebrate Paleontology Vol. 19 No. 1 (1999): 91-100. Web. 5 Apr. 2014. Williams, Vincent S. et al. “Quantitative Analysis of Dental Microwear in Hadrosaurid Dinosaurs, and the Implications for Hypotheses of Jaw Mechanics and Feeding.” Proceedings of the National Academy of Sciences of the United States of America Vol. 106 No. 27 (2009): 11194-11199. Web. 5 Apr. 2014.
Ceratopsians and Pachycephalosaurs are closely related in their characteristics. Ceratopsians processed a saddle-shaped boney frill that extended from the skull to the neck and typically had horns over the nose and eyes. The most popular was the triceratops, which could reach over 26 feet and weigh in excess of twelve metric tons. Their frills served as two major functions. It protected the vulnerable neck from being harmed. The second major function that the frill provided was due to the fact that the frill contained a network of blood vessels on its underside, which were used as a means to get rid of excess heat. The Pachycephalosaurs were considered to be bipedal. They were also found to have thick skulls, flattened bodies, and tail that were covered in an array of body rods. Pachycephalosaurs were thought to have been more than fifteen feet long and processed a skull that was surrounded by a rounded dome of solid bone. It was thought that they used their heads in combat or mating contests, but that was disproved fairly recently, which I will discuss later in the paper. Both Ceratopsians and Pachycephalosaurs were “bird-hipped” and both of these suborders contained a backwards pubic bone. Both were Marginocephilia, or “fringed heads”, which is one of three clads under the Orinthiscia order. They were also herbivore dinosaurs that inherited their fringe at the back of the skull from earlier ancestors.(2) Their classi...
In his peer-reviewed article, “Sexing fossils: a boy named Lucy?,” James Shreeve discusses, in detail, a study on sexual dimorphism and possible speciation in Australopithecines in Hadar, Ethiopia, based on the famous A. afarensis specimen, “Lucy.” In the article, “Lucy’s kind takes humanlike turn,” the author addresses sexual dimorphism and speculates on sex-based differences in behaviors in A. afarensis. The two articles have differences and commonalities with each other in content and both present research methods and conclusions on topics including sexual dimorphism, sex-based behaviors, and speciation in Australopithecines, which receive critical analysis.
...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.
The idea of cloning dinosaurs and other prehistoric life became popularized by the 1992 film Jurassic Park (based on Michael Crichton’s 1990 novel). Though it may have sparked new interest into the field of paleontology, it did so with deceiving inaccuracies. However, the technical fallacies of the actual dinosaurs are somewhat forgivable as it added to the film’s dramatic appeal. Velociraptor, as depicted in the film, was about the size of a grown man. In reality, velociraptor came to about the kneecap. Furthermore, velociraptor would more likely have been covered in feathers rather than the lizard-like skin portrayed in the movie. One scene shows velociraptor fogging the window of a door. This is an endothermic or warm blooded trait as it implies the dromaeosaurid’s body temperature is above the temperature of his environment. There is also no evidence of dilophosaurus bearing a neck frill, and brachiosaurus did not have the ability to chew his food in a circular motion (iguanodon was the first dinosaur to develop this technique by acquiring back molars to allow for equine or bovine-like chewing). Fortunately, tyrannosaurus remained very close to his biological authenticity, with the only paleobiological errors stemming from a lack in computer animation such as rudimentary ball and joint programs. However, the erroneous nature of the deoxyribonucle...
In an article entitled Tyrannosaurus was not a fast runner, those experts, John R. Hutchison and Mariano Garcia provide us with a detailed account of a recent study they did. Their study is described in an article entitled Biomechanics: Walking with tyrannosaurs by Andrew A. Biewener. Biewener states that Hutchinson and Garcia, “introduce a new biomechanical approach,” to the question of dinosaur movement and provide an, “a...
5 The Field Museum. (2002). New Species Clarifies Bird-Dinosaur Link. Science Daily [online], 14 Feb 2002. Available at http://www.sciencedaily.com/releases/2002/02/020214080242.htm
As time progressed, Ichthyosaurs transitioned their body like features from a lizard-shaped body plan to a fish-shaped one through the early and middle Triassic periods. In 1927, the first bone fragments were foun...
This idea was reinforced when a Diplodocus (a type of sauropod that lived in the late Jurassic) skull was found in 1884 that contained a large hole in the top of the head. Scientists believed that this hole contained the entire nostril (Witmer 2001; ). This positioning of the nostrils was used for many other models of dinosaurs as well, but when it was discovered that...
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
"The Dino Directory-Dilophosaurus." The Dino Directory. The Trustees of the Natural History Museum, London. Web. 12 Mar 2014. .
...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.
Raymond Rogers, David Krause, and Kristina Curry Rogers found significant evidence that the carnivorous dinosaur, Majungatholus atopus, was also a cannibal (Krause et al 2003). The dinosaur remains of the Majungatholus atopus were dated in the late Cretaceous Period from 65 to 70 million years ago. The Majungatholus atopus inhabited the plains of the northwestern Madagascar and bones and teeth continue to be found throughout the Maevarno Formation and within the channel-belt deposits of the Anembalemba Member. The Majungatholus is commonly found, along with other vertebra taxa in ‘bonebeds’ in the Madagascar area, which is probably the reason this dinosaur is still preserved. The trio discovered teeth marks in many bones of the ribs, ilium, and precaudal axial skeleton co...
As time goes on, more and more fossil record of dinosaurs are richly known; more and more relative research project work on. An encouraging imagination that species of dinosaurs are not extinct and they evolve to birds was emerged. Dinosaurs are still here. They are still all around in the Human Age. It sounds crazy. Nevertheless, it seems clues are everywhere. There is a kind of dinosaurs, call Sauroposeidon, could raise its massive head over eighteen meters into the air, but this was only possible because their neck bones were so light, almost 85% hollow (name). Like Sauroposeidon, other kinds of dinosaurs’ bones were honeycombed with empty spaces. In fact, everybody already knows that birds have hollow bones as well, and a lot of people believe that’s an adaptation for flight. Scientists learned that birds inherited their hollow light bones from their extinct ancestors, gigantic dinosaurs. And there is another clue. (name)The lungs of dinosaurs are designed like normal birds, which can be seen all around world every day. Focusing on the respiratory syst...
Dinosaurs lived in the Mesozoic era, a time of the "terrible lizards" a name in which the Greek described them as. Since they were large reptilian creatures they laid eggs like any other of their kind. Dinosaurs had a unique posture in which they would hang their arms with a firm look that made their movement further accessible similar to mammals or birds. Some dinosaurs evolved from a bipedal, meaning that they walked on two legs and others evolved from quadrupedal also meaning which walked on four legs . An example of this would be a tyrannosaurus rex which is a bipedal and a triceratops which is a quadrupedal
A number of different theories have been assessed throughout the course of this research to attempt to reach a conclusion as to the reason behind the extinction of the Tyrannosaurus Rex. Although all arguments are credible, and supportive with educated information and data, the most conclusive theory of all is The Alvarez Asteroid Impact theory.