Penguins (3059 words) Essay Example For Students

Penguins (3059 words) Essay PenguinsThe signature Species of the Southern Hemisphere (Antarctica) the mascot if you will is the penguin. There are not one and no fewer than seventeen species of penguins. Penguins are flightless birds in which several factors are contributing to the reduction of the penguin population. These contributing factors are both man-made and naturally occurring. ?The origin of the word ?penguin? has been the subject of debate for a long period of time. Researchers and historians theories range from reference to the amount of fat (penguigo in Spanish and pinguis in Latin) penguins possess to the claim that the word was derived from two Welsh words meaning ?white head.? (Sparks and Soper, 1987) Penguins are comical and funny birds. Blue/black on the upper half of their body and white on the lower half, they look as though they are all dressed up for a formal dinner or show but have no place to go! Penguins are flightless birds, which have adapted to living in the cooler waters of the Southern Hemisphere. They generally live on islands and remote continental regions that are free of land predators. Their inability to fly has been detrimental to their survival on land. Some species of penguins spend as much as 75% of their lives in the ocean, yet they all breed on land or sea ice attached to land. The seventeen species found today are thought to have evolved from flying birds more than forty million years ago. To date, the discovery of all penguin fossil fragments has been limited to the Southern Hemisphere. ?Records show that prehistoric penguins were found within the range of present-day penguins.? (Sparks and Soper, 1987)All penguins have a very similar torpedo-shaped body form, which is conducive for swimming. They have a large head and a short neck with an elongated body. Penguin species vary greatly in size. For example, the Emperor penguin is the largest of the penguin species, standing 3.7 feet and weighing between sixty and ninety pounds. The smallest penguin in the species is the Fairy penguin, standing only sixteen inches and weighs less than 3 pounds. Penguins wings are highly modified to form a stiff paddle-like flipper used for swimming. ?Each flipper is covered with short, scale like feathers. The long wing feathers typical of most birds would be too flexible for swimming through water.? (Sparks and Soper, 1 987) A penguins tail is short and wedged shaped with fourteen to eighteen stiff tail feathers. The legs and webbed feet with visible claws on a penguin are set back on the body so that when on land, the penguin is able to stand. ?Penguins walk with short steps or hops, sometimes using their bills or tails to assist themselves on steep climbs.? (del Hoyo, et al., 1992) When in the ocean swimming, penguins use their feet and short stubby tail as a rudder to guide them through the water. Penguins bones are solid and heavy which help them to remain submerged to reduce the energy that they need for diving. Penguins are able to withstand the extreme cold because of the insulation provided by their feathers. Feathers are highly specialized, broad and closely spaced helping to keep water away from the penguins body. Penguins have more feathers than most birds, having about seventy feathers per square inch on their body. Most penguin species goes through one complete molting cycle per year, which usually happens after breeding season. ?The exception to this is the Galapagos penguin which annually go through 2 molts.? (del Hoyo, et al., 1992) For penguins, molting is a very important process because feathers wear out when penguins come in contact with each other, as well as with the ground and water. The molting period varies between one species to another. Usually the time period is anywhere from thirteen to thirty-four days. Regular preening of the feathers is essential as penguins obtain oil from their tails to coat their feathers for waterproofing. Penguins in warmer temperate zones have a thinner plumage of feathers and fat layer than their counterparts of the polar species. To keep warm in near freezing waters, penguins have a highly developed heat exchanged system of blood vessels in the flippers and legs which helps the heat loss at the core of the body. To avoid heat loss in a penguins body, the penguin has 2 internal temperatures. A penguin has a normal body temperature and a temperature of the environment close to the limbs of the body. Tropical penguins can overheat very easily; so in order for them to lose the body heat, they usually use their flippers to get rid of excess heat. They also have bigger flippers than their polar penguin ancestors. Penguins communicate with each other by different ritual behaviors such as head and flipper waving, calling, bowing, gesturing and preening. Penguins c ommunicate by ?displays? or vocalization and performing physical behavior. ?They use many vocal and visual displays to communicate nesting and territories along with mating information. They also use displays in partner and chick recognition, and defense of intruders.? (Sparks and Soper, 1987) Territorial disputes can lead to aggressive postures such as stares, pointing and even charging each other. Also during courtship and mating, other rituals are included which are called ecstatic displays. In these particular displays, an unattached male penguin will pump his chest several times, stretch his head upwards and move his flippers about away from his body. During this display, the male penguin also emits a loud harsh sound. In doing this, other male penguins in the colony begin to exhibit the same behavior which in turn begins the breeding cycle within the colony. When breeding occurs, one is unable to distinguish male and female penguins because they are not sexually dimorphic. The re is one particular penguin that one can be told apart called the Crested penguin. Other ways of telling which penguin is male or female is that males are usually more robust and have larger bills. Also during mating season, female penguins are identifiable by muddy footprints left behind by males during mating activity. Acid Rain EssayThe dumping of garbage and trash in the ocean affects all kinds of marine life including the penguins. Penguins have been found tangled in debris, which causes death or serious injury. In addition to trash dumping, oil dumping also poses a great threat to the penguin population. When their feathers are tainted with oil, weatherproofing is reduced and their insulation fails. They are then at great risk of hypothermia. In addition, when trying to preen their feathers; they can ingest oil, which poisons them and causes their internal organs to fail. Although oil spill disasters such as the Exxon Valdez spill off the coast of Alaska had a devastating affect on the population, oil also enters into the waters via ship sludge and residue. Facilities are available for ships too properly dispose of their sludge and residue; however, unfortunately these facilities may not be utilized as it may be cost prohibitive and therefore, illegal dumping is then opted. The dumping of oil waste is permitted; however, the rate must be 15 parts of oil to a million parts of water. This formula is not followed as the risk of being caught is so small compared to the cost of the mixing of the formula. Oil also enters into the marine habitat through land run-off. ?The U.S. Academy of Sciences estimated in 1990 that 37% of oil pollution of the worlds marine environment enters the sea from the land. Other sources estimate that 45% comes from shipping (12.5% from tanker accidents); 9% from the atmosphere, 7.7% from natural sources and 1.5% from offshore oil exploration and production.? (Environmental News Network). In conclusion, the responsibility for the future existence of the penguin population lies mainly with the human race. Our ability to cause changes in climate snowballs thus creating changes in global and local patterns of ocean productivity. We have altered, and continue to alter, the natural environment and habitat of these wonderful creatures. Historically, the direct exploitation of penguins by humans created a huge risk to their survival. Currently, as humans create more creative uses for penguins and their skins, we pose a greater risk of impacting their existence. The ability to control and monitor the use of these animals is complex and difficult. The need for protecting marine habitats for all kinds of marine life has become serious. We have the ability to cause the extinction of far too many creatures. As of December 4, 1998, a number of conservation groups gathered and formulated a report on the penguin population. They believe that 9 penguin species should have been endang ered or were close to being endangered, and 2 more species close to being threatened. Previously, only 5 of the total seventeen penguin species were considered threatened. Based on the above-referenced conservation groups statistics, more than 50% of penguin species may be close to endangered. If we do not take an active stand on the protection of these amazing birds, we stand a chance of creating yet another ?dinosaur,? available to our children only through history and science books. Science Essays