Реферат на тему Penguins Essay Research Paper The penguin Sphenisciformes
Работа добавлена на сайт bukvasha.net: 2015-06-18Поможем написать учебную работу
Если у вас возникли сложности с курсовой, контрольной, дипломной, рефератом, отчетом по практике, научно-исследовательской и любой другой работой - мы готовы помочь.
Penguins Essay, Research Paper
The penguin (Sphenisciformes) has been a fascination to numerous people including scientists and researchers alike. They have distinctive characteristics and an interesting classification system. Their eating habits, unique way of breeding and predators are just a way of everyday life that fascinates scientists and researchers. The species status still remains in danger and can hopefully be helped.
This unusual bird stands on short legs and walks with a clumsy waddle. These birds cannot fly which is how they got to be called Penguins, which means flightless. All species of penguins have short-bodies and necks. They also all have short thick feathers, which form a kind of waterproof coat. Most penguins feathers have feathers that are just white on the stomach and are black and blue on the back. Some have patches of brightly colored feathers on their necks. Theses birds keep warm from the harsh Antarctic conditions by thick layers of fat on their bodies. Their wings developed into flippers, which serve as paddles to help propel them in the water. They also have webbed feet which when combined with the flippers make them excellent swimmers and divers.
The species are divided into four groups for easy identification. The groups are as follows, I. Large, with orange or yellow patches on the sides of the upper neck (Species 1-2). II. Medium-sized, crested with orange or yellow lines on each side of the crown above the eyes (Species 3-8). III. Medium-sized, with no crest or yellow colour on the head, but usually with stripes of white or black on the head or breast (Species 9-14). IV. Small, with out crest or yellow colouring on heads (Species 15-17) (Alexander 148). An example of each is as follows: Group I, the Emperor penguin. Group II, the Royal penguin. Group III, Adelie penguin and Group IV, the Whit-filppered penguin.
The Emperor penguin is the largest penguin with the most southern range. The top of the head, chin, cheeks and throat are black, with a broad orange semicircle patch on each side of the upper neck. They have a long bill, which curves down, and a short tail composed of 20 feathers. The Royal penguin s neck, chin, and throat are white. They have a broad orange band across the forehead and a short tail consisting of 14 feathers. The main difference of this type of penguin as with the others is having white on the chest and throat. In group III, the Adelie penguin has a black throat, head, and cheeks. Their eyelids and under parts are white. They have a short bill and a very long tail consisting of 14 feathers. This type of penguin walks very slowly with a waddle. When on snow or ice, it travels on its breast using its flippers and feet for motion. In group IV, the White-flippered penguin, as inferred by its name is all white except for a light greyish-blue on its under parts. While their may be many different physically looking types of penguins, they all have similar eating and breeding habits.
All penguins eat fish. For example, the Emperor penguin has short wings which enables them not to fly, but are used for fast and quick underwater motion. They can dive from up to 250 meters, which makes them the deepest divers of the penguin species. Most penguins eat krill and surface fish, but this enables them to eat other types. Even though most penguins live in southern areas where they have short summers and their food is limited by sea ice and krill is their only source of food.
Even though penguins spend much of their life in the water, they lay eggs and raise their young on land. For the later purpose they come ashore on islands on desolate coasts and hop, run, waddle or scramble over rocks, and even up hillsides to their breeding grounds or rookeries (Alexander 147). All four species have a different type of breeding process. For example, the Emperor and Adelie penguin have similar, yet different types of breeding behavior. The Emperor females lay only in egg in June and then they get up to leave for the sea. It is then up to the males to do the rest. They pick up the egg and place them at their feet where it is then covered by a warm layer of skin. It is at this time that the male penguin looses half of their body weight. It is up to the females to collect food for themselves as well as the males. In contrast, the Adelie penguin breeds in a different in a different way. These penguins spend their winters packed in ice and in the spring, they follow the sun south towards other penguin colonies. They are similar to the Emperor penguin in that the female lays the egg, in this case two, in November and leave for the males to take the eggs and incubate them. The males rely on the females to get them food just as the male Emperor penguin does. If the female does not return, the males will leave the eggs for the predators.
In the Antarctic the penguins are found by rocky shores and different amounts of sea ice. Compared to the summer, the ice doubles in the winter. But throughout the year there are many nutrients, which attract many mammals and sea birds. During the warm months, the penguins are threatened by many predators.
Several species prey on penguins. The largest is the orca; killer whale. Along with the killer whale is the Leopard Seal, which has the penguin as their main source of food. They live on packed ice and are fast in the water, but slow on land. These two mammals are the main threat to adults where large birds such as the Giant Petrels and Giant Skuas, are predators for the young penguins. Just as in any life, they have learned to adapt to the ways of predators and their environment.
Today the penguin population is decreasing. According to Pough (298), until man appeared the evolutionary adaptation to ocean life and a diet of fish was highly successful. Pough also said that the bird was abundant with few enemies. Besides the threat of predators, there is the threat of pollution. According to Cramp (35-36), besides the problem of oil there has been a finding of a certain type of pesticide called organochlorines and mercury. They pass from one food chain to another.
There is hope that we can learn more scientific characteristics to help continue their extraordinary species. The specific identification system, breeding patterns and predators can help us aide in helping the existence of the species. There may never be a time when we will fully understand the impact penguins have on our lives, but the more we research the more we can learn to help them survive.