The Warm and Cold Blooded Nature of Dinosaurs
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.
Until recently, scientists believed the chances of finding a fossilized dinosaur heart were extremely slim. The heart belonged to a 66 million year old dinosaur found in Harding County in Northwestern South Dakota. The dinosaur, found in 1993, weighed over 650 pounds and was 13 feet long. The dinosaur was in fairly good condition with the exception of the left side of the skeleton. The small, plant-eating Thescelosaurus, nicknamed ‘Willo’ has been acquired by the North Carolina Museum of Natural Sciences. Thescelosaurus was an ornithischian, or "bird-hipped," dinosaur that lived in the latter stage of the Cretaceous period. This was approximately 1 million years before the end of the dinosaur era. Native to North America, its range extended from the northern United States up into Canada. Since using the 3-D software to reveal Willo's heart, scientists have also used it to create 3-D images of the fossil's skull, and of remains from other dinosaurs in the museum's collection. (Fisher, Paul)
A group of scientists from North Carolina and Oregon used medical technology to search an iron-stained concretion inside the specimen’s chest. With the assistance of imaging equipment and software, they were able to reconstruct 3-dimensional structures through the interior of the concretion. The images reveal a heart that was more like that of a bird or a mammal than those of reptiles, significantly adding to evidence suggesting that at least some dinosaurs had high metabolic rates. In addition, the heart appears to have been four chambered with a single aorta, which is most commonly found in mammals or birds.
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...
In the early 1800’s, a new discovery that left paleontologists in awe was the fossil finding of the immeasurable amount of species of reptiles, Ichthyosaurs. Greek for “fish lizards”, these fossils were found all over the world. Because these large aquatic reptiles migrated just as whales do today, paleontologists have had the amazing advantage of collecting fascinating bone fragments throughout the past 177 years. Ichthyosaurs swam the ocean life from about 245 million until about 90 million years ago- approximately the same time dinosaurs ruled the land. The earliest Ichthyosaur fossil findings were in parts of Canada, China, Japan, and possibly Thailand. Countless fossils came from coatings of limestone produced out of the ocean-floor ooze that was predominantly superior at preserving very well facts of the creatures it digested (Perkins 2).
“66 Million–Year–Old Dino With A Heart.” Media Kit 17 April 2000. North Carolina University. 2000 <http://www.dinoheart.org/mediakit/index.html>.
In both of Hawthorne’s short stories “Young Goodman Brown” and “The Minister Black Veil” and in Miller’s The Crucible, jumping to conclusions has ruined people’s lives. Jumping to conclusions without fully understanding the situations allows one to end up going in the wrong direction. If young Goodman Brown had taken the time to think about the meeting, he would have realized it was a dream. If the people had taken the time to ask Mr. Hooper why he was wearing the mask, then Mr. Hooper’s life would not have been so gloomy. Finally if the court had have taken the time to make sure Abigail was not lying, then her victims lives would have been saved. If we as humans can learn to investigate and try to think things through before we act, then in some cases people’s lives may be saved.
Since kindergarten, our heads have been filled with fantastic pictures and stories about the great dinosaurs that have long been extinct. But like a lot of our childhood education, scientific information is often simplified and exaggerated by teachers, parents and the media. The case of the T- Rex is an exceptional example of how the media can create a stereotype based on incomplete and outdated information, which ends up asserting itself back in mainstream popular culture. Thus, a certain myth of the Tyrannosaurus Rex being a speedy eating machine, becomes a social “fact” based on fiction.
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
Many people once believed that pterosaurs were weak flyers, or at least the larger ones were. The idea was that they used their large wings to glide instead of flap like flying creatures. This is now known to be false. Pterosaurs were also thought to be dinosaurs with similar anatomical features. Studies have shown now though that since the pterosaurs were not flappers but active flyers, their hearts were similar to those of mammals with four chambers, needed for an active way of life, unlike reptiles. In the past century, pterosaurs fossils have been known to be found with fur, which leads scientists to believe that pterosaurs needed insulation to keep in heat which indicated pterosaurs were active like mammals and warm blooded. 1
Spector, B. (2013). Implementing organizational change: theory into practice. (3rd ed.). Upper Saddle River, NJ
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.
Religion was one of the most powerful influences on medieval medicine. People of the medieval period used to think that illness was either a punishment or a test of faith. Their way of curing this illness was to pray and help the poor (Medieval Medicine and the Plague, 12). Some would even whip themselves in hope for forgiveness (The Usborne Internet-Linked Medieval World). Saints held great power. They were thought to be able to perform miracles and cure the ill. People would start to venerate the saints. They would even go on pilgrimages to shrines of saints to ask for help with ill loved ones. The church, of course, did not discourage this. (Su...
Surface area to body mass ratio plays a central role in determining an organism’s ability to generate and retain body heat. How might this have played a role in dinosaur evolution, and what are the specific advantages of being large and slow versus small and fast with respect to heat generation and retention?
Change is the only constant in life. And therefore it should be understood as part of a continuing work in progress that calls for a much broader canvas that seeks out competing voices, and works with the resulting ambiguities, contradictions and tensions of messy reality (Graetz, F. & Smith, A., 2010). In this submission I try to show that organizational change is majorly based on the environment surrounding it much more than the desire of the members or change agents working in that organization. This view diverts from that of Lippitt, (1958) who suggests that implementing planned organizational changes successfully depends on premeditated interventions intended to modify the functioning of an organization. It also diverts from the traditional approaches to organizational change that generally follow a linear, rational model in which the focus is on controllability under the stewardship of a strong leader or ‘guiding coalition (Collis, 1998). In this discussion therefore, comparison made between the different philosophies of change and I try to show that successful change implantation largely depends on an organizations appreciation of what goes on around it rather than what they have planned as a strategic direction.
In separate studies, researchers Daniel Ksepka and Daniel Thomas noticed that the penguin fossils showed grooves on their humerus. These grooves were signs of a humeral arterial plexus—a penguin’s form of thermoregulation. The system of arteries and veins in their flippers ensured that warm blood cooled down by the time
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.
Norell, Mark, Lowell Dingus, and Eugene S. Gaffney. "Why Did Nonavian Dinosaurs Become Extinct?" Discovering Dinosaurs: Evolution, Extinction, and the Lessons of Prehistory. Berkeley: U of California, 1995. N. pag. Print.