Crocodiles today are adapted to both land and water. These animals have land movements that are only found in mammals. They perform asymmetrical gaits, such as bounding and galloping. These movements are thought to have evolved from the Triassic era. Ancestors had a larger role on land, and a more upright posture. A bracing system has been proposed, which limits vertebral loads. This bracing system in crocodiles today allows for both up-down and side to side movements. Changes in the bracing system are thought to be why crocodiles have switched from amphicoelous to procoelous. It is also the reason why body size is linked to movement. The researchers looked at how intervertebral joint stiffness affected movement in nile crocodiles. Researchers found that stiffness was lowest during sideways motion. In ventral and dorsal flexion, stiffness increased. Crocodiles have different column flexions …show more content…
There was no difference in stiffness between up and down motion. Mammals are the opposite. They are stiffer in sideways bending than in up-down bending. Many mammals have stiffer dorsal extension than ventral. Physical measurements accounted for 28 – 52% of variation in stiffness. Therefore, a large percentage of variation is unaccounted for. Joint size and ligament properties may account for some variation. Spine morphology may also be a good indicator of stiffness. Centrum height is a good predictor of up-down stiffness. Centrum thickness is a good measure of side to side stiffness. Centrum length was also a predictor of stiffness. Facet joint orientation is a good indicator of stiffness. Intervetebral joint movement is constrained due to the close contact of the facet joints. The pre-facet joint spacing is associated with increased stiffness in all directions. Lamina width is associated with increased up-down stiffness. Combined, these are both good indicators of vertebral column
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...
The musculoskeletal system offers support and stability for your body so we can properly function and move around. Different types of muscle within the muscular system include cardiac, skeletal, and smooth. The reason our bodies are capable of producing movement is because of the way our muscles contract. Our adult skeletal structure is made up of 206 bones that all differ in shapes and sizes. The composing parts that make up the system include the bones, joints, and muscles that all connect so we’re capable of moving. These components allow for our bodies to maintain a stable structure that can keep us upright. The axial skeleton refers to the skull, the vertebral column which supports the spinal cord, ribs, and sternum. It offers protections
The way of the Lemurs evolution is very particular. Once, Madagascar was attached to the African Continent, but Madagascar separated from the mainland of Africa. Therefore, this is the reason why the Lemurs still exist today, thanks to Madagascar's isolation. This is the reason that the Lemurs have not changed much from their ancestors. In order to avoid other primates and predators the Lemurs became nocturnal, so they were able to survive. “Note the large eyes, a nocturnal adaptation, typical of both ancient and modern prosimians who are active at night.” (Larsen, 2014). However, what they could not avoid was the threats of humans, even though humans evolved from them. As Larsen states; “The five types of vertebrae in primates, including lemurs and humans, create a flexible column allowing a wide range of movement. The cervical, thoracic, and lumbar vertebrae are the true, or movable, vertebrae, responsible for bending, twisting, and stretching.” (Larsen, p. 164). As a result of this mobility, the locomotion behaviors of the Lemurs is that they walk quadrupedal and they do leaping horizontally from branch to branch. To do this, the Lemurs developed strong muscles and flexibility, but also the ability to stand straight
The results from the experiments supported the hypothesis that the batoid pelvic girdle shape correlated with the type of locomotion. They found that the form of locomotion utilized by the batoid had a greater determining factor on the shape of the pelvic girdle compared to the phylogeny. An important discovery of this experiment showed that the shape of the pelvic girdle of a batoid can be used to predict the swimming and punting mode, and the order to which the vertebrate
Kinesiology can be defined as the study of mechanics of body movements, so I think that is very important to know the meaning of movement when studying kinesiology. Everything in kinesiology has to do with the movement. Every action the body takes is a movement which is what kinesiology is. You cannot be successful in the field of kinesiology no matter what you are doing if you do not understand what movement is. It is the study of human movement, performance, and function by applying the sciences of biomechanics, anatomy, physiology, and neuroscience. It looks at movement and which muscles are involved to create movement relating to strength exercising and sports technique. Movement is an act of changing physical location or position or of
If you were to live during the tertiary period, this would be one of the things you would often see. All of the mammals that existed during that time period were terrestrial. They all were land dwelling mammals. Before J. G. M. Thewissen and colleagues’ discovery in Pakistan, many scientists believed, since the constant new discoveries twenty years ago, in what the numerous fossils from North America, Pakistan, and Egypt have revealed, “…these early cetaceans had mobile elbows and external hind limbs with articulated knees. However, they were fully aquatic, except for Ambulocetus, which was amphibious-much like sea lions” (Walking with Whales).
This type of joint mainly includes long bones as it’s necessary for movement in the skeletal
Approximately 4 million years ago a wonderful evolutionary phenomenon was happening in Africa. Early hominids, man’s ancestors, were beginning a giant leap in their evolution. These hominids were moving out of the forest and beginning to walk upright, out on the open plains (Fagan, 98). This change from quadrupedalism was the most significant adaptation that ever happened to these early hominids. It caused many adaptations that make man what he is today. This process occurred in early hominids for many different reasons, each reason helping to perfect the upright walking posture. Bipedalism is thought to have occurred because of changes in environment, feeding habits, thermal regulation, and behavioral mechanisms.
The main function of the coccyx is to serve as a place of attachment for some crucial muscles and ligaments. It also serves as a weight-bearing structure along with the...
The skeletal system is composed of many bones, joints, cartilage, ligaments, and tendons. The key functions of the skeletal system are to supply a supportive frame for the body, to shield the internal organs such as the heart and lungs. Providing attachment points for muscles is also another function as this enables the parts of the animal to have good locomotion, the long bones produce bone marrow. However, for this report, I will be concentrating more on the joints of the canine skeletal system. The joints are the articular exteriors at the end of the bones, they are shielded by a coating of cartilage. There are three main types of joints within the canine skeletal system they consist of the fibrous joints, these do not allow any movement
The good news is poor posture can be easily corrected, which will redirect the forces applied to the intervertebral disc. The bad news is a lot of people have poor posture.
Retrieved 14 May 2014, from http://www.teachpe.com/a_level_analysis/movement_analysis_webpage.html. Thibodeau, G., & Patton, K. (1993). "The Species of the World. " Chapter ten: Anatomy of the muscular system. In Anatomy and Physiology (1st ed., p. 252).
The platypus is covered with a thick water-resistant fur, excluding its bill and feet. It’s body it streamlined, has short limbs and webbed forefeet to propel itself through water using an alternative kicking motion. The webs on the for...
As it continues to develop, the bone becomes spinter-like and the tibia continues to grow past it. To understand this transformation, Joao Botelho conducted two experiments: One focused on the fibular reduction in birds while the other focused on the development and evolution of the perching digit of birds.
Hippopotamuses are very fascinating animals to study and observe. With their semiaquatic lifestyle, they appear to be more closely related to whales than other hoofed mammals. Their ability to be versatile in their habitats helps protects them against different dangers that they face. During this research paper I learned many facts about hippopotamuses that I was not previously aware of.