Реферат по предмету "Иностранный язык"


Basking Shark Essay Research Paper Among the

Basking Shark Essay, Research Paper

Among the masters of the sea, lies a sluggish monster. Cetorhinus

maximus is just that, although more generally known as the Basking shark. This

interesting animal has some unusual characteristics which include its physical,

behavioral, reproductive, and feeding attributes. Other details about the Basking

shark, consist of its habitat, distribution among the waters, ecological

relationships, and research being done on this gentle shark.

Basking sharks have been known to range from between twenty to fifty

feet long, but are more commonly closer to thirty feet (Allen, 1996, 158). The

smallest recorded Basking shark was sixty-five inches long, which is the

estimated size of one at birth. There have been no significant differences found

to exist in the *age*-length relationships of C. maximus populations World-Wide.

Although all Basking sharks are large, the females tend to be quite a bit bigger

than the males, which is probably because they have to carry a whole other

organism within (Harman, 1996, 21).

Basking sharks have, at some point in time, also been known as the

elephant shark, the Bone shark, sailfish shark, and sunfish. The reason this

shark is occasionally referred to as the Bone shark, is because when they die,

they sink (their density is greater then the water’s density) and are ravaged

among the sea floor, by rocks, etc. (Steel, 1985, 132). However, when they do

finally wash up on shore they are usually quite mutilated; their skeletons are all

that remain. Hence the name, Bone shark. Although the Basking shark most

appropriately resembles the Whale shark, its closest relative happens to be the

* I could not find, in any of my many sources, the life span of the Basking shark*

great white shark (http://www.askjeeves.com/MetaAnswer.asp?MetaEngine

=Lycos&logQID=8F7C6F5E10E0D2119B5300104B2AFFF7&qCategory=SCI_&q

Source=0&frames=yes&site_name=Jeeves&scope=web&r=x&MetaTopic=The+B

asking+Shark+Project&MetaURL=http%3A%2F%2Fwww.isleofman.com%2Finte

rests%2Fshark%2Findex.htm&EngineOrdinal=3&ItemOrdinal=1&ask=basking+s

hark+metasearch&MetaList=http%3A%2F%2Fwww.isleofman.com%2Finterests

%2Fshark%2Findex.htm&ask.x=22&ask.y=1).

When alive and healthy, Basking sharks are grayish brown, and even

black on the top half of their body and a much paler version of those colors on

the bottom. They have a thick covering of spiky denticles along their whole body

(Allen, 1996, 273). Their enormous amount of denticles, make their skin

stronger than cowhide (Allens, 1996, 160).

To give an idea of the size of the Basking shark, picture this scene in your

mind: you and your family are out sailing. A “small” six ton Basking shark jumps

out of the water next to your boat. As it crashes against the water in its

downfall; the rise of the wave that is caused is as tall as a three story building,

possibly even larger (Allen, 1996, 273). Hopefully that gives you at least a small

idea of how massive these sharks are. However, in case that wasn’t convincing

enough, here are some measurements taken off of a mere twenty-nine foot

Basking shark: head: 1 ton; liver: 1850 lbs; fins:1 ton; tail: half a ton; skin: 1 ton;

meat and back: 3000 tons; guts: half a ton; stomach and intestines: half a ton to

1 ton; the total of that whole shark is almost seven tons (Allen, 1996, 271-272)!

If you think those numbers are amazing, listen to these tasty facts: Basking

sharks have a hundred or more teeth, to a row, and row upon row upon row of

tiny, practically useless teeth (Blassingame, 1984, 90). Their mouth is so big

that a child can walk into it without even bending down (Harman, 1996, 22)!

The swimming patterns of Basking sharks greatly reflect their behavior

among one another. They have been known to swim in a line, one behind each

other, and also to swim round and round in circles, giving the impression of a

“sea serpent” (Allens, 1996, 271). Basking sharks either travel alone, in pairs,

or in schools of up to 100 members (http://www.askjeeves.com/FinalAnswer.asp

?qCategory=SCI%5F&Link=http%3A%2F%2Fwww%2EEnchantedLearning%2E

com%2Fsubjects%2Fsharks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoo

m+Sharks&Answers=1&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%

7C&ajparam_qid=1401&site_name=Jeeves&scope=web&ask=Where+can+I+fin

d+information+on+the+animal+basking+shark%3F). They even got their name

through one of their behavioral traits: basking in the sun. These sharks have a

habit of laying on the surface of the water with their backs exposed. With their

first dorsal fin guiding them along the water, just sunbathing (Allen, 1996, 272).

Although the Basking shark is generally known for it’s gentle nature, when

harpooned, or endangered, this sluggish animal, can turn into a sailors worst

nightmare (Allens, 1996, 273)!

Basking sharks are believed to be ready to mate between the ages of two

to four years (Harman, 1996, 26). They usually have one or two live young and

are thought to have the largest babies (in length) at birth (Harman, 1996, 26).

Mating usually occurs in May and the gestation period lasts approximately two

years, if not more (Steel, 1985, 133). For quite a few years, scientists thought

that Basking shark females did not have embryos. And the most widely

accepted theory had been that Basking sharks are viviparous, conceiving their

young at the surface, and have birth in the deep ocean (Allens, 1996, 273).

Recent research has proven differently. Female Basking sharks do in fact have

embryo’s, along with huge amounts of eggs that are consumed by the embryo’s

during the gestation period (Steel, 1985, 133). A very odd trait of the Basking

shark, is that young sharks are rarely found and have been thought to remain in

deep water until full-grown (Steel, 1985, 134). They do however, swim away

from their mothers right after they’re born. So, the mother does not care for the

young sharks after birth (http://www.askjeeves.com/FinalAnswer.asp?qCategory

=SCI%5F&Link=http%3A%2F%2Fwww%2EEnchantedLearning%2Ecom%2Fsub

jects%2Fsharks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&A

nswers=1&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam

_qid=1401&site_name=Jeeves&scope=web&ask=Where+can+I+find+informatio

n+on+the+animal+basking+shark%3F).

The mouth of the Basking shark is not only very large, but also quite

effective during feeding times. These sharks feed by keeping their mouths wide

open while swimming and just have a continuous flow of water going in, which

the gill rakers strain for plankton. Gill rakers are bristle-like fibers with a sticky

coating which serve as a filter to find food (along with taking oxygen from the

water). Scientists estimate that an average size shark, swimming at two knots,

can filter a thousand tons of sea water over it’s gills every single hour

(Blassingame,1984, 91). Basking sharks are strictly plankton-eaters. However,

one theory states that the sharks semihibernate in deep water and lose their

gill rakers, in which case they go deeper to feed on plants and small shellfish

(Blassingame, 1984, 92). Losing their gill rakers in winter is a pretty universally

known theory, since evidence of sharks without gill rakers, but growing new

ones during winter, have been found (Blassingame, 1984, 92). What they eat

over winter, or whether or not they just hibernate, is not yet an established fact.

Basking sharks are usually found in temperate waters with lots of

plankton. Temperate waters are the waters that are not considered tropical or

arctic (Antarctic). They are temperatures like from San Diego to Alaska. Oddly

enough, they usually enjoy the water much colder than your average sea

creature. They are usually found off North America, ranging from

Newfoundland to North Carolina. In the Pacific, they are commonly found from

the Gulf of Alaska all the way down to Baja, California. During the winter they

have been thought to disappear completely from around North America but are

still found occasionally in the Pacific.

The Basking shark’s, major enemy are humans. Men hunt them for their

meat and fins, but primarily for their lavish supply of oil. In one shark, you can

usually find sixty to seventy gallons of oil, which humans use for industrial

reasons. C. maximus, which is believed to be the only kind of Basking shark,

has an adaptation which helps when trying to protect themselves from man

(Allen, 1996, 273). That adaptation is their body slime, which quickly rots fishing

nets, so they can escape (Steel, 1985, 132). The only other enemy of the

Basking shark are parasites. The blood sucking lamprey (Petromyzon marinus)

stick onto these sharks throughout the seas and the only way the sharks can rid

themselves of the lampreys are to jump to awesome heights from the sea (Allen,

1996, 272). The number of Basking sharks is at this time unknown, but could

very easily be decreasing since the it is hunted by humans for its meat, fins, and

oil (http://www.askjeeves.com/FinalAnswer.asp?qCategory=SCI%5F&Link=

http%3A%2F%2Fwww%2EEnchantedLearning%2Ecom%2Fsubjects%2Fsharks

%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&Answers=1&ajpa

ram_list1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam_qid=1401&site

_name=Jeeves&scope=web&ask=Where+can+I+find+information+on+the+anim

al+basking+shark%3F).

Quite a few organisms would be effected by the removal of the Basking

shark from the ocean, however in different measures. Without the sharks,

plankton would thrive to an unruly amount, which therefore would cause less

sunlight to reach the deeper areas of the ocean, killing off, or hurting the

organisms which use that sunlight to survive.

Many sharks are being researched by modern day scientists to help fight

life-threatening diseases. Basking sharks in particular, are used for research in

trying to destroy cancer and heart disease. This is because their enormous

supply of oil contains chemicals which is leading medical researchers to cures

for these often fatal illnesses (Allen, 1996, 160). Basking shark cartilage

contains an abundance of a substance that stops the growth of new blood

vessels toward solid tumors, which overall, restricts the growth of tumors

(http://www.askjeeves.com/FinalAnswer.asp?qCategory=SCI%5F&Link=http%3

A%2F%2Fwww%2EEnchantedLearning%2Ecom%2Fsubjects%2Fsharks%2Fsp

ecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&Answers=1&ajparam_lis

t1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam_qid=1401&site_name=

Jeeves&scope=web&ask=Where+can+I+find+information+on+the+animal+baski

ng+shark%3F). Other chemicals within the Basking shark have been found to

lessen, or slow down blood clotting (http://www.askjeeves.com/FinalAnswer.asp

?qCategory=SCI%5F&Link=http%3A%2F%2Fwww%2EEnchantedLearning%2E

com%2Fsubjects%2Fsharks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoo

m+Sharks&Answers=1&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%

7C&ajparam_qid=1401&site_name=Jeeves&scope=web&ask=Where+can+I+fin

d+information+on+the+animal+basking+shark%3F).

Basking sharks are among the most interesting and mysterious giants of

the sea. It is hard to believe that the only creature killing these sharks off are

humans, and yet many groups, including English Nature (formerly the Nature

Conservancy Council) recommend the species be listed as an endangered

species. However, that idea has been repeatedly rejected by the UK

Government (http://www.askjeeves.com/FinalAnswer.asp?qCategory=SCI%5F&

Link=http%3A%2F%2Fwww%2EEnchantedLearning%2Ecom%2Fsubjects%2Fs

harks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&Answers=1

&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam_qid=1401

&site_name=Jeeves&scope=web&ask=Where+can+I+find+information+on+the+

animal+basking+shark%3F). It just goes to show, that ecological relationships

should not be messed with by foreign means. I hope that one day all creatures

can live in complete balance with one another, and each gain success and

failure equally.




Не сдавайте скачаную работу преподавателю!
Данный реферат Вы можете использовать для подготовки курсовых проектов.

Поделись с друзьями, за репост + 100 мильонов к студенческой карме :

Пишем реферат самостоятельно:
! Как писать рефераты
Практические рекомендации по написанию студенческих рефератов.
! План реферата Краткий список разделов, отражающий структура и порядок работы над будующим рефератом.
! Введение реферата Вводная часть работы, в которой отражается цель и обозначается список задач.
! Заключение реферата В заключении подводятся итоги, описывается была ли достигнута поставленная цель, каковы результаты.
! Оформление рефератов Методические рекомендации по грамотному оформлению работы по ГОСТ.

Читайте также:
Виды рефератов Какими бывают рефераты по своему назначению и структуре.

Сейчас смотрят :

Реферат Государственные реформы Петра I 3
Реферат Электроснабжение механического цеха машиностроительного завода
Реферат Разработка состава и технологии модельной смеси лекарственной формы для лечения конъюнктивита
Реферат Самая лучшая книга по воспитанию детей, Васютин Александр
Реферат Маркетинговое исследование рынка парикмахерских услуг
Реферат Специфика Я-концепции и самооценки женщин, страдающих бесплодием
Реферат Технология реабилитации людей, страдающих игровой зависимостью
Реферат Российская урбанизация 1860-1914 годов в трудах отечественных историков
Реферат Аудит учета расчетов с поставщиками и подрядчиками
Реферат Инвестиционный климат стран Европы и Африки
Реферат Государство и право Российской империи в период абсолютизма 2
Реферат Gun Control It Is Needed Essay Research
Реферат Системный анализ особенностей фонематического восприятия у старших дошкольников с задержкой псих
Реферат Состав преступления - единствеенное основание уголовной ответственности
Реферат Conflict Containment And Resolution Essay Research Paper