Organism Physiology is the method in which many diverse living organisms are considered to have developed from earlier forms during the history of the earth that can be defined as Evolution. Several organisms have evolved as a result of environmental changes within their habitats. Example is a diagram of a whale and details about how the whale has evolved physiologically and has become adapted to fit the environment. Kingdom: Animalia, Phylum: Cordata, Class: Mammalia, Order: Cetacea, Sub-order: Odontoceti, Family: Delphinidae, Genus: Orcinus, Species: Orca.
Whales occupy all oceans and major seas, even some are in larger river systems. They are very large animals. They can grow up to 100 ft. or more in length. They can weigh up to 200 tons or more. Whales live in families called pods. These pods vary in numbers and consist of family members and family friends.
Whales live in these families their whole life. Group living is safer when other whales or sharks attack. It also makes it easier to find food.
Whales are always migrating. They travel to find food, breed and have young. Whales do not have eyelids. They rely on thick oily tears to protect their eyes. Whales hear from little holes behind their eyes. They talk to each other by making high pitched sounds like whistles, clicks, squeaks, rattles, and groans. Whales inhabit all oceans and the seven seas; some also inhabit larger river systems. They are extremely social organism and use communication for the function of hunting, defense, and reproduction. In general a dolphins live pods of up to a dozen individuals. Dolphin pods can emerge temporally forming a super pod the emerging pods may exceed thousands of dolphins. Attachments in pods are not set; interchange is regular. On the other hand, whales can generate great social bonds; they will remain with wounded or individuals in poor health, even assisting other whales to breathe by bringing them to the surface if required. Whales arewidely classed as predators, but their food ranges from microscopic plankton to very large fish.
Males are called bulls; females, cows. The young are called calves. Because of their environment, whales are conscious breathers: they decide when to breathe. All mammals sleep, including whales, but they cannot afford to fall into an unconscious state for too long, since they need to be conscious in order to breathe. Whales also communicate with each other using lyrical sounds. Being so large and powerful these sounds are also extremely loud depending on the species. The most dangerous predator for the whale is mankind and climate change. Man slaughters whales for their meat, fat, and for being in the same location where they fish. There studies at this time being done to evaluate the influence of pollution in the water and the effects on whales. Whales are threatened by climate change and global warming. As the Antartic Ocean warms, krill populations, that are the main food source of some species of whales, reduce dramatically, being replaced by jelly like salps. . Whales give birth to live young, and the mother nurses the calf with her milk and provides care. The calf is nursed by the mother for one and one half years to three years and a mother will stay with her young three to eight years. Whales are thought to live about 40-80years. Whales vary basis of their ecosystem and what is necessary for them to survive in their ecosystem (Getten, 2006). All whales, dolphins, and porpoises species are related.
Fossil data has been discovered from the early Eocene epoch that point toward information that whales were already aquatic 45-50million years ago. It is thought that animals that spent a great amount of time hunting for food around water areas and went through a period in an amphibious stage before becoming adapted to live in the water and the animal became dedicated to the water. Records show that by in their teeth it took millions of years for true cetaceans to develop (Brakes, Simmonds 2011). The whale has adapted to the environment in many ways from the once amphibious animal it is thought to have evolved from. Fossil evidence reveals that after prehistoric whales decided to be aquatic, it did not take long for bones of the hind limbs to disappear. The front limbs evolved into flippers and the powerful tail is their most important forward motion mechanism. Anatomically, dolphins’ bodies have adapted to become more efficient to move in the water. Whales, like dolphins are marine mammals and like all mammals they require oxygen to survive. Unlike other sea creatures such as fish, a whale would suffocate in water if it did not have a blowhole for oxygen. The blowhole is situated on or near the top of their head and acts as an airway passage for breathing. Whales cannot breathe through their mouth because the esophagus (food passage) and trachea (oxygen passage) are completely separated from each other. Although whales must breathe oxygen they can spend up to 90% of their lives underwater. The eyes of a whale are relatively small when compared to the rest of its body. Their eyes are well adapted to aquatic life and secrete oil used to lubricate and protect their eyes from debris and other chemicals in the ocean.
They are not capable of secreting tears as humans do, but their cries can be heard vocally from many miles away. They have a condensed body with a somehow a tapered head that caused the vertebrae neck to fuse together. Instead of a main blood supply to the brain on the exterior of the neck, the whale blood flows through an artery in the vertebrae that supply a continuous supply of blood, which is most vital when diving into the depths of the ocean. The skin of a whale is extremely smooth, hairless, dense, and not do have glands. Their skin is kept smooth by continuously sloughing off and being restored. On average their skin is restored at a speed nine times faster than a human. Whales have a tendency to depend on their sense of hearing to survive. Other senses have had to adapt for survival in the blackness of the ocean’s deepness.
The structure of the whale’s melon (the fatty tissue in front of the blow whole) functions as a lens to direct sound when the dolphin generates high pitched clicks for echolocation. When the sound echoes back the small bone under the chin, called trepan bone, receives the sonic report and stimulates the brain by means of the inner ear. By means of echolocation, whales can estimate distance by measuring the time between releasing the clicks and the return of echoes. Through this incredible ability, whales can consider the size, shape, direction of movement, and distance of objects in the ocean water (Getten, 2006). In conclusion dolphins have adapted agreeably to survive in the depths of the ocean, seven seas and in large rivers systems. They have evolved in structure and ability to reproduce successfully and flourish. Having the intriguing ability of echolocation provides whale’s considerable advantage while feeding in the environment in which they live. They are extremely energetic, gentle, and intelligent. The only main threats
to whales are humans through various ways and climate change. If whales are left alone in their ecosystems their species would be able to survive successfully.
References Brakes, P., & Simmonds, M. P. (2011). Whales and dolphins: Cognition, culture, conservation and human perceptions. London, UK: Earthscan. Getten, M. J. (2006). Communicating with orcas: The whales’ perspective. Charlottesville, VA: Hampton Roads Pub. Co. Whales and Dolphins Website : Whales. (2011, March 11). Retrieved December 7, 2013, from http://dolphins-and-whales.zoomshare.com/11.html