Introduction
Dinosaurs refer to a wide set of animals that dominated vertebrates living on land for more than one hundred and sixty years since the end of Triassic era to the late Cretaceous era. The species of dinosaur began disappearing in the third incident of crustacean extinction event. According to reports from the fossils, avian developed from a group of dinosaurs called theropod in the Jurassic era (Paul 14). A few of the birds evaded this period including their descendants. Never the less, birds in some instances have been classified as dinosaurs.
These are a set of animals consisting of more than nine thousand avian and perciform fish. Several kinds of avian dinosaurs have been identified, ranging from those that fly to those that do not fly. Fossil remains belonging to dinosaurs have been excavated in all parts of the world. A few of the dinosaurs were carnivorous whilst others were herbivorous. Furthermore, some dinosaurs have been having two pedals, others with four pedals.
Dinosaurs having two pedals assume the highest ultimate speed in running as opposed to those with four limbs. Never the less, some dinosaurs walking on fours sprint at a fast rate as opposed to their bipedal counterpartss. A case in point is the avian descendants which possess fast moving muscles of the upper arm which have evolved by time to form wings and can propel the dinosaur at very electrifying speeds especially under tension or when running after a prey.
Most of the present day animals have their ancestral roots among the dinosaurs’ .The world’s main vertebrates that fly are the birds. In addition to this, most of the dinosaurs have been reduced in sizes and are said to make nests including laying eggs in the nests as well as flying at very high speeds. The first fossils were discovered in the nineteenth century. Since the discovery, the remains have been preserved in various historic sites such as the museums.
Every excavated remain has followed the same suite making museums rich of dinosaur remains. Dinosaurs have appeared in best-selling editorials as well as films expending their fast moving characteristics. New discoveries of the same have been aired by media on regular basis. More so, the eroding dinosaur image as ancient monster has attracted the use of ‘dinosaur’ into gaining entry into vernacular by describing anything that is obsolete, huge, tending towards extinction and slows in motion.
Modern definition
According to Phylogenic classification, dinosaurs refer to modern birds (Neortnithes), their recent ancestors’. Avian species have been characterized by presence of ostriches; these definitions encompass theropods, sauropodomorphs, ankylosaurians, stegosaurians, ceratopsians, and ornithopods (Paul 67).
General description
Dinosaurs can be defined as land based archosaurian reptiles constituting of limbs erected below the body that existed during the end ofs Triassic and the end of Cretaceous periods. Most of antediluvian animals are purported to be dinosaurs (Paul 76). Dinosaurs constituted a large portion of animals living on land and which resembled mammals very closely.
Other sets of animals were very small and limited to the size of a rodent or cat. However, Repenomamus giganticus fed on infant dinosaurs. Since 2008, various dinosaur species have been identified. One of the Dinosaurs was found to be living in aerial or marine environments despite the fact that some theropods with feathers could fly. This simply means that some of the spinosaurids constituted of temporal aquatic characteristics.
Physiology
Most people studying the origin and evolution processes among dinosaurs have given different opinions regarding thermal regulation which closely intertwines with speed in a given animal. Initially a hot discussion ensured with respect to the beasts ability to regulate the body temperatures.
Currently studies have supported the fact that these eroding species existed in regions of low temperatures hence most of them had thermal regulatory mechanisms to counter the cooler climatic conditions. Hence, the argument concurs with those who asserted that the dinosaur’s ultimate speed during sprinting was very low; hence they were slow moving creatures. An example of this fossil is that of the polar bears found in Antarctica region.
Discovery of avian fossils have also supported the thermal regulation concept among Neortnithes. The study of blood circulation among a set of avian dinosaurs is a true representation of all endothermic creatures. Theropods displayed an active lifestyle blood circulatory system that is characteristic of endothermic animals.
Warm-bloodedness among many animals can result from various mechanisms. For example, Mammals and avian whose body sizes are average have been compared with endothermic dinosaurs. These birds make use of their energies to increase their body temperatures above that of the surrounding.
Small sized avian have insulators in terms of presence of feathers and fat which aids in thermal regulation. Huge mammals like elephants, however, have a minute surface area compared to its volume which is in agreement with Halden’s principle. This feature enhances thermal regulation which resulting from the cooling of the body temperatures during hot seasons via flapping of the ears. This characteristic is important especially during running after a hunt.
Dinosaurs speed
The legs of human beings are up right with knees that are straight due to their vertical bodies that put the C.O .G (centre of gravity) in alignment with the socket of the hip. Since both the body and the head of the bipedal dinosaurs were kept level as well as ahead of the hips despite the long tail which countered the balance, the femur sloped in front in order to maintain the feet below COG.
This organization is however extremely represented in birds with short tails whose femoral bones are close to the horizontal line on walking so as to maintain the feet and knees a distant enough in front, hence during running, birds femur tends to strongly swing towards the back as opposed to the front (Martin 57).
Two sets of dinosaurs namely the sauropods and the stegosaurs developed elephantine biased towards straighter-jointed columnar limbs. The knee structure was reorganized in that it maintained wholly articulated upright. More so, the mobility of the ankle was reduced whilst the hind limbs were kept short.
This adaptation restrained the body from being pushed in to actual running irrespective of the size. For instance, young elephants always run at a slower pace as opposed to their parents in that at least one foot is always stack to the ground during high speed running.
Dinosaurs with straight limbs should have been much slower in running than elephants whose speed is equal to or less than 15 meters per minute or 25kilometres per hour (Paul 245). Neither, is it an issue to ascertain that medium and small dinosaurs bearing lengthy, slender flexed hind limbs would run at similar speed to galloping mammals and terrestrial birds whose speed is between forty to sixty kilometers per hour.
Challenges have been experienced in attempts to find out the highest speed in which heavy weight dinosaurs can attain. Some electronic technologies have claimed that tyrannosauras dinosaurs could attain a highest speed of approximately forty kilometers per hour equal to elephants of the same size which is the human beings sprinting speed.
Since large tyrannosaurus had better running adaptations as opposed to elephants, there lacks a likelihood of this kind of creatures having been slow, furthermore, some individuals indicates that enormous theropods capability to run was twice that of similar sized elephants and that this speed was equivalent to that of the non-thorough bred horses and rhinos.
Till date, the electronic analysis of dinosaurs locomotion processes in addition to storage of energy in the already stretched tendons of the limbs and springing resonance effect of the tail and torso. Neither, has it occurred that the capability of the programs used in finding out the speed could successfully ascertain extreme animals’ performance as well as estimate the modalities on which extreme dinosaurs which include the supersaurapods were able to maintain an upright posture with minimal movements irrespective of their huge bodies.
This is very important to note, however, this query has lacked answers for many decades (Lockley 12). It is even more depressing to think about all this mystery since track-ways indicate that the vast surapods were terrestrial never the less, their appearance looks irregular and their weight cannot give support to elephants whose speed is low and which bears a small body size. The supersaurapods needed super muscles and power to run across Mesozoic lands.
They also needed pretty adaptations like well built fiber muscles as well as tendons that have already been tensed to undergo evolution so as to enhance movement. If their muscles were pre-tensed then it is obvious that the huge dinosaurs might have very high running speed as opposed to computer analysis results.
General Anatomy and Speed
The heads of the dinosaurs ranged from delicate structures to well formed structures. The sinuses or nasal passages were well constructed something that was very popular with the archosaurs. Most dinosaurs maintained prominent orbital openings, where as in others the opening was nearly closed off.
As opposed to other mammals that consist of prominent face muscles, and just like avian and reptiles, dinosaurs did not have muscles of the head thus the skin was in direct contact with the skull. This adaptation makes it easier for head restoration in dinosaurs as opposed to other mammals.
The outside nares are located in distant place from their nose despite the extent of the nasal cavity which extends in the exterior. Among some set of sauropods, the nasal cavity have been found extended in the anterior part of the skull, over the sockets of the eyes. Previously, it was said that this adaptation enhanced snorkeling of the dinosaurs during submerging. Recently it has been purported that retracted nasal cavities evolved so that it can protect them from irritation as they fed on cactus.
Most of the vegetation constituted of soft vegetation and this adaptation really helped the dinosaurs. The flabby nasal cavity extended interiorly such that nares on the exterior were positioned in normally close to the snouts tip. Nothing can proof that dinosaurs had proboscis. The skin that covers huge cavities in the orbits anterior of most of the dinosaurs smoothly extended to the exterior. The muscles of the jaw also protruded outside the cavities of the skull of the orbital sockets.
Snakes constituted fangs that were trimmed sharply. Amphibians on the other hand had teeth that could be seen upon closure of the lips. The amphibians also did not have muscles that covered the mouth cavity.
This adaptation seems to be satisfactory to many of the sauropods and theropods (Lockley 78). One distinct species is the spinosaurs whose arrangement resembles that of a crocodile with the front teeth spaced widely in different sockets. Hence this set of dinosaurs might have lacked lips and their ugly lips left uncovered on closure of the jaws.
Ornithischians came up with embryonic teeth. In therizinosaurs and Ornithischians the beak was based on the anterior of the mouth where as in theropods including most of the avian the teeth were replaced by the beak. Most of the birds with beaks do not have lips and cheeks .Never the less; condors have diminished mouths due to the fact that their side jaws are protected by elastic tissues of the cheek which vary from muscles of the cheek covering side teeth.
For sauropods and Ornithischians the side teeth were always inset, the surrounding cavities constituted smooth surfaces including the foramen which extending the soft tissues.
This implies that the well structured elastic cheeks enveloped the side teeth. This adaptation is clearly spelt out in Ornithischians and the tissues of the cheeks some which underwent ossification especially among the ankysaurs where cheeks protruded towards the beak.
The dinosaurs trunk vertebrae moved in various directions such as the dorsal convex or the straight line that varied from feeble to strong (Strickberger 57). The nature in which dinosaurs articulated more so during ossification of the tendons of the spinal meant that their backs were more stiff as opposed to those of lizards as well as other mammals though dinosaurs trunk vertebrae were not jointed.
Dinosaur ribs seemed to be more perpendicular yet this varied from one dinosaur to another. The hips and the stomachs of the carnivorous theropods were tiny indicating the diminished digestive system and also their running abilities. Large carnivorous dinosaurs could fast during hunger and porch for prey afterwards hence their stomachs remained hollow during the time of hunting.
On the other hand, herbivorous dinosaurs had enlarged hips and bellies which extended to the very extreme in that it adversely affected the fattest dinosaurs. The ankylosaurs shoulder blades were more warped along the extended axis so that it fits on the abrupt change from shoulders which were narrow to the bulged abdomen.
The muscles of the trunk were made light and this adaptation enhanced their movement. The gastrointestinal system was made flexible to aid in swallowing of food. The tail and the hip inclined con the same line as they appeared in vertebral of the trunk. Amongst the sauropods and therizinosaurs, the tail and hip were upwardly flexed with respect to the vertebrae of the trunk.
This enabled the trunk to be clutched strongly anchored upwards whilst the tail and hips maintained a horizontal plane thus an upright posture of the head was increased where as the dinosaurs ability to run on the hind limbs was maintained. Since most of this animal’s weight concentrated on their hind limbs apart from the tail which acted to counter the weight of the body, most the dinosaurs reared upwards including those whose forelimbs were longer than hind limbs.
Assessing the speed of Dinosaur
A critical aspect to note in finding out the power and speed of dinosaurs is limb muscles mass, which constitutes a bigger percentage of the sum of mass in the high speed mammals as opposed to slow speed mammals (Paul 45). Lack of muscles on dinosaur fossils has made it difficult to accurately ascertain the exact speed of dinosaur, the best that can be done is just but finding an approximate figure which has had discrepancies from one researcher to another.
The complicated muscles of the limbs of the existing mammals find their roots in the history of dinosaurs. Dinosaurs preserved the plain structure reptile muscles which are prominent till date. For instance, the main muscle which are still visible in most dinosaurs and reptiles but lacking in mammals and avian are caudofemoralis tail based muscles that aided in pulling the legs backwards at the time of propulsive stroke.
Despite the fact the exact muscle dinosaur sizes cannot be identified, their comparative sizes amid various sets can be estimated. A case in point is the hips of the reptiles which consists of an undersized ilium in that the muscles of thighs are forced to be narrow restricting their size. The extended iliac of the mammals and avian hold a powerful and broad group of muscles of the thigh (Paul 56). The ancient prosauropods and herreraurs ilium was undersized hence must have consisted of very tiny muscles of the thigh.
Some of the dinosaurs had deep and extended ilium holding a very large group of muscles of the thigh promoting sustaining power. To some of the dinosaurs the trend was very extreme. On the other hand, tyrannosaurids and ornithomimids which belong to the family of ostriches consisted of large pelvis demonstrating the presence of distinctively enormous muscles of the legs with the ability to produce enough power during high speed propelling.
Longer hips were observed in ceratopsid dinosaurs which enhanced large hind limb muscles which promoted the fast fending off of the muscles. Surprising the large ilium lacked in saurapod dinosaur. This is due to the fact that this kind of dinosaurs did not have to move fast. This is the same issue with the elephants which lacked huge muscles beneath the knees due the fact that the limbs in which the shank muscles support immobile and short.
This was true of stegosauras and sauropods. Fast moving animals constitute a huge stack of shank muscles that manipulate the extended long, movable limbs through the tendons. For bipedal dinosaur such as avian, huge collection of limbs that resemble the drumstick muscles beneath the knee anchoring on enemial like projections in front of the joints of the knees.
Bringing back dinosaurs entirely makes their surface contours to be so simple in that their tails, limbs, and legs into to tubes that are simplified tubes and smoothing above the body topography. Among the saurapods, the neck vertebra protuberance, were prominent on the necks as they appear in giraffes.
Since the oesophagus and the trachea of sauropods well held up amidst the necks and their cervical ribs, the lower part of their necks should have been flattened. As opposed to two legged dinosaurs, four legged dinosaurs are huge with enormous body weights. The dinosaur’s skeletons were adapted to bearing heavy loads as opposed to running. The 3-toed two legged dinosaurs used to walk on twos.
This is what the cursorial dinosaurs adaptation to running. This feature is important and it has been well brought gout gin the modern avian which are ancestors of coelurosaurian. Digitigrades features enhance the length of the limbs since the metatarsal bones contribute to the length of the leg increasing the animals COG. An example is the limbs of human being which are used for jumping or running, during running, the runners sprint on their toes.
Estimating the Maximum Running Speed of Dinosaurs
William Sellers and Phillip Manning attempted to find out the maximum running speed of dinosaurs using robot. In their finding they noted that multiple body simulations by use of approaches such as evolutionary robots seem to give steadfast estimates of the highest speeds attained by dinosaurs (Strickberger 87). For instance, multibody simulations, with minor variations in patterns of muscle activation as well as starting conditions resulted to constant estimates.
The ultimate running speed in animals is very technical and poses a lot of challenges in estimating this parameter. This is because as far one might try to estimate using an animal on pace, the animal might not run as fast as it could run. Furthermore most of the estimated values of the running speed of animals are given with regard to the observation findings which were conducted under compromising situations.
The ultimate speed of running among dinosaurs differs from one species to another. Whereas the situation may deem to be straight forward in humans in that the two hundred meter sprint may be above or below 0.1 of a second the maximum speed attained can exceed the normal speed by 12m/s. The situation in humans is apt for well known athletes with well built muscles as opposed to the estimations (Paul 67).
The above estimates concur with the biochemical techniques which estimate eighteen meters per second among ostriches and thirteen meters per second for emu. The differences in the mass of muscles affects the maximum speed and these changes have a great influence on the average speed of the dinosaurs. Another method of measuring the highest speed attained by the dinosaurs is by estimation the loading capacity of the bones and the value compared to the speed of the animals whose speed is known.
Conclusion
All in all, dinosaurs were ancient reptiles that existed during the reptile’s period. These creatures dominated the planet hundreds and hundreds of years ago and faded way as time went by and until now we can only see the fossils. Dinosaurs were terrestrial reptiles whose locomotion was on an erect posture.
The most unique thing about the dinosaurs was the structure of their distinct hips that caused their hind limbs to protrude beneath their bodies and not spread out from the sides (Martin 56). When these animals evolved from ancient archosaurs, they were pedaling on twos but evolved to quadric-pedals. The evolution of muscles and the hip structure an adaptation that has enhanced its locomotion and other characteristics. Dinosaurs have been purported to have been the ancient reptiles that ran at a lightning speed (Lockley 78).
However, there lacks a clear evidence to ascertain this claim. Some of scientists have tried to estimate the maximum running speed of these animals using conventional robotic instrument with no success. Dinosaurs have evolved from time and time and from the distinct creatures birds, crocodiles have emerged. In evaluating the speed and power is the mass of the muscles of the limb (Martin 67).
Despite the fact that the exact mass of the muscles of limb cannot be determined due to the absence of the muscles on the fossils, their comparative size amid various groups can be produced. Scientist has tried estimating the maximum speed of dinosaurs.
Approximating the speeds of dinosaurs differ from one method of estimation to another. For instance, some scientists have argued that young children might out do their counterpart in running.
The various methods of evaluating the ultimate speed that can be achieved by dinosaurs are the same techniques which can be put to task in evaluating the speed of the animals in today’s world. For instance, the dinosaurs walking speed range between four to six kilometers per hour to six kilometers the ultimate running speed has been purported to range between thirty seven to eighty seven kilometers per hour.
The ultimate speed which has been said to be the maximum speed of the dinosaurs is the current speed of the fastest terrestrial Animals. This speed differs from one species to another and it is also dependant on the approach used. Each approach used has its own confounding factors that yield different results.
Works Cited
Lockley, Martin. Tracking Dinosaurs: a New Look at an Ancient World. Denver: CUP achive, 1991.Print
Martin, Anthony. Introduction to the Study of Dinosaurs. London: Wiley-Blackwell, 2006. Print
Paul, Gregory. The Field Guides. New York: Princeton University Press, 2010.Print
Strickberger, Monroe. Evolution. New York: Jones & Bartlett Learning, 2005.Print