Warm Blooded Versus Cold Blooded Dinosaurs
At a time, scientists believed all dinosaurs were cold-blooded. However, with a recent discovery of a dinosaur found with a fossilized heart in the northern part of South Dakota in 1993, many paleontologists are starting to think that there were some dinosaurs that were warm blooded.
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
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Because warm blooded animals don’t have to rely on their environment for body temperature, they are able to hunt at any time of the day or in any season, which is a great advantage over cold-blooded animals. Therefore this “type of intense activity needs a fast metabolism which is much too high for a cold-blooded animal. Secondly, cold-blooded animals have a hard time living in cold climates and dinosaur fossils have been found in the colder environments” (Eschberger). However, scientists believe warm blooded animals would have suffered from the heat in warmer climates, where many fossils have been discovered. Beverly Eschberger discusses how dinosaurs must have been only warm blooded animals due to the factors of, bone structure, and histology, growth rates, predator to prey ratios, speed and agility, rate of evolution, similarities with birds, and insulation. She also explains the disadvantages of being a warm blooded animal: “a much larger expenditure of energy to maintain elevated metabolism and a commensurate increase in food requirements” (Eschberger). Just as the conclusion that dinosaurs were truly warm blooded becomes clearer, factors from the cold blooded side switch everything around. Gigantothermy, rate of food supply, respiratory turbinates and lung structure all cause scientists to believe dinosaurs were in fact cold-blooded. There have been many attempts to find the real resolution of whether or not dinosaurs were warm or cold
A dinosaur has an antorbital fenestra with an open hole hip socket. The definition differs from the term used informally because it helped understand how the dinosaur moved and how they were categorized as species. There are four general characteristics that dinosaurs have as a result of their synapomorphies which are permeated acetabulum, ball-shaped head on proximal femur, the Cnemial crest on the proximial tibia, and an ascending process on astragalus. These four dinosaur synapomorphies are related to vertical limb support.
This researcher proposes that the dinosaurs did not die of heat, in fact she thinks the opposite, that they froze to death instead. Both articles have the same idea about a meteorite hitting the earth yet there is no concrete evidence as to what caused the meteorite to strike and what it did when it got here.
Although the Ediacaran period was well before the first appearance of dinosaurs it shows that there were fossils many years ago. When dinosaurs first appeared things had changed there was still shallow water which meant that bones could be fossilized.
The reading passage proposes three theories which support the idea that a dinosaur which is called edmontosaurus survived in the winter by migrating to the south, the more hospitable region than the extremely cold in the North Slope. However, the professor in the listening respectively contradicts each theory in the reading passage by using strong evidence as support.
In a study published in Cretaceous Research and conducted in October 2012 by Anthony R. Fiorillo, Thomas L. Adams and Yoshitsugu Kobayashi, evidence of dinosaurs was based on the finding of an unnamed nonmarine sedimentary package of rocks. Found in the Wrangellia Terrane and considered to be Cretaceous age, the rocks are light colored with medium grey shales and indicate a bounty of horsetails, ferns and gymnosperm wood.
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
Many other animals besides dinosaurs lived during the Cretaceous. These animals were very diverse and included pterosaurs, ancient flying reptiles,
Jurassic Park introduces the world of biotechnology in genetic engineering. The line is crossed from what is possible to what is imaginable. The question of control, over nature, is false. Man cannot control nature. Jurassic Park is a good example of how genetic modification is a hindrance towards the environment.
Animals differ in their abilities to regulate body temperature (thermoregulation). We sometimes use the terms "cold-blooded" or "warm-blooded." Most reptiles feel cold to the touch, while mammals and birds often feel warm.
Every so often a discovery is made that attempts to shake up pre-conceived notions of how the dinosaurs actually lived or how they came to be. On June 22, 2000, in Oregon, scientists announced the discovery of the oldest known animal to have feathers. Though no records indicate how the age of the animal was determined, the
The word dinosaur was invented in 1842 by Richard Owen. Dinosaur comes from the Greek word “deinos” and “sauros” which translates to fearfully great lizard (“Learn about Dinosaurs”). Dinosaurs are always named in Greek and usually named after their unique fossils, where they 're found, it’s size or a person. Before a dinosaur can be officially named it must be approved by the International Commission on Zoological Nomenclature. It’s difficult to figure out how dinosaurs sounded, mated, behaved, what color/pattern they were and which ones are male or female. Paleontologists have however been able to discover that dinosaurs hatch from eggs, their bones have growth rings which can help figure out their age and that the larger dinosaurs lived for roughly 100 years and smaller ones for less. All dinosaurs evolved from other reptiles during the Triassic period. Dinosaurs are either herbivores or carnivores and are divided into two major groups. Bird hipped, Ornithischian, or lizard hipped, Saurischa. In the Saurischa hipped dinosaurs the pubis bone is down and to the front but in Ornithischian hipped it is point down and towards the tail (“Zoom Dinosaur”). The next step was to examine how dinosaurs behaved and their characteristics.
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
Dinosaur extinction: An analysis of events and theories that possibly led to the dinosaurs' demise.
The biggest mystery surrounding the dinosaur is how did they die? For over 130 million years dinosaurs ruled the earth. Then 65 million years ago, at the end of the Cretaceous period, they died out.
Rapid climate change also ends up on the suspect list of possible dinosaur extinction events. During the latter part of the Cretaceous Period continents broke up causing volcanoes to erupt and fill the sky with gas and ash resulting in a drastic climate change (“Dinosaurs Climate Change and Biodiversity”). The shifting of continents changed the Earth’s landscape, altering weather patterns and overall climate (“Dinosaur Extinction Theories”). Also, over a long period of time, climate gradually changed. Ocean habits changed, temperatures grew much more extreme causing scorching summers and frigid winters (Norell, Dingus, and Gaffney). Radical temperature changes like these led to a green-house effect, making life for the dinosaurs a lot