Dolphins Essay Example for Free

Dolphins Essay Bottlenose dolphins can grow to be thirteen feet long and weigh up to 600 pounds (Bottlenose Dolphins). This makes bottlenose dolphins the largest of the beaked dolphins (Dolphin Research Center). Bottlenose dolphins have slick and rubbery skin with no sweat glands or hair. Their epidermis is ten to twenty times thicker than that of other mammals. It can be replaced every two hours, which is nine times faster than human skin. The peeling of their skin helps to reduce drag when they swim. The skin is dark gray on their backs, and fades to white or pink on their bellies. This coloring is called countershading. From above the dolphins blend in with the dark water below, and from underneath they blend in with the sunlight. Countershading helps dolphins hide from predators and prey (Bottlenose Dolphins). Bottlenose dolphins are piscivors, or fish-eaters. They have eighty-eight to one hundred small, sharp teeth for grasping slippery squid and fish (Parker and Burton) (Dolphin Research Center). When catching fish, dolphins usually herd a school of fish together and then dash through the school one at a time to feed. It has been observed where 200 bottlenose dolphins were in a single row, working together to find food. Dolphins can also use their tail flukes to toss a fish out of the water and then retrieve the shocked prey (Bottlenose Dolphins). If a dolphin catches a large fish, it will smack the fish on the ocean floor or the water’s surface to break it into smaller portions (McClintock). After a dolphin catches its prey, it uses its tongue to swallow the fish and push the water out of its mouth (Dolphin Research Center). Dolphins can eat up to thirty pounds of fish in one day, so it is helpful that they have three stomach compartments, similar to that of a cow (McClintock) (Lockley 69). Bottlenose dolphins find fish by using echolocation. This is when a dolphin sends out a beam of short sonar pulses from its melon, or forehead. The beam reflects off of fish or other objects and echoes back to the lower jaw. The echoes are then sent to the ear bones where they are characterized. Using echolocation, dolphins are able to locate prey that is buried up to one and a half feet under the sand (Cahill 140-141). Bottlenose dolphins are excellent swimmers. They can jump up to sixteen feet in the air. Three to seven miles per hour is their normal swimming speed, but they can reach speeds of eighteen to twenty-two miles per hour. Dolphins also porpoise, which is when a dolphin swims fast enough to repetitively come out of the water and back under the water in one swift movement. This uses less effort than swimming fast at the ocean’s surface. When dolphins swim in deep open water, they often dive. They dive to 150 feet regularly, but they have been recorded diving up to 2,000 feet (Bottlenose Dolphins). When a dolphin needs to breathe, it comes to the surface, exhales, and then inhales. If a dolphin stays underwater for a very long time, it can exhale at over 100 miles per hour (Cahill 77). It only takes about 0. 3 seconds for dolphins to breathe (Bottlenose Dolphins). Dolphins exchange 80% of their lung air with each breath; when humans breathe, they exchange only 17% (Bottlenose Dolphins). They come to the surface to breathe every twenty-eight seconds when they are not diving, but they can hold their breath for up to twelve minutes (McClintock) (Bottlenose Dolphins). Before a dolphin can hold its breath for a long time, it has to slow its heart rate down to twelve beats per minute. A slow heart rate helps to conserve energy and oxygen while diving (Dolphin Research Center). In order for dolphins to be able to swim, they have to have fins. Bottlenose dolphins have three different types of fins on their bodies. The most recognizable is the dorsal fin. It is located in the center of the back and is the cause of dolphins sometimes being confused with sharks. The dorsal fin is helpful for balance but is not essential. Dolphins also have flippers on both sides of their bodies called pectoral fins that are used to steer. The bones in pectoral fins look similar to human hands because they have five digits. The two parts of a dolphin’s tail are called flukes. Tail flukes are made up of tough connective tissue with no bones or muscle. The tail’s spread is 20% of the total body length. The dolphin’s back muscles move the flukes up and down to push the dolphin through the water. All of the fins and flippers use the process of countercurrent heat exchange to conserve body heat. This means that the arteries in the fins are surrounded by smaller veins so that some of the heat from the blood is transferred to the blood in the veins instead of being released to the environment (Bottlenose Dolphins). Dolphins need to conserve heat to stay warm in cooler waters. The lifespan of a bottlenose dolphin is twenty to thirty years. They can reproduce every three years for their entire lives starting at the age of six (Bottlenose Dolphins) (Cahill 98). The gestation period lasts twelve months. Baby dolphins, called calves, are usually born tail-first to prevent drowning, and the umbilical cord between the mother dolphin and calf snaps during birth (Cahill 98) (McClintock). â€Å"85% of all firstborn calves die† (McClintock). Newborn calves typically weigh twenty-two to forty-four pounds and are thirty-nine to fifty-three inches long (Bottlenose Dolphins). Since dolphins are mammals, calves drink milk produced in the mother’s body (World Book 296). Mother dolphins have to swim constantly with their calves in their â€Å"slipstream† because newborns do not have enough blubber to easily float (Hecker). At about four months old, young start to eat fish and are entirely weaned from milk between the ages of one year and eighteen months (Lockley 169). Each dolphin develops a signature whistle at one month old. In order for calves to recognize their mothers by their whistle, mothers whistle to their calves almost constantly for several days after birth (Bottlenose Dolphins). A dolphin will stay with its mother for at least six years and some dolphins stay with their mothers for their entire lives (Bottlenose Dolphins). Bottlenose dolphins are very social animals. They travel in pods, which are groups of two to fifteen dolphins (Bottlenose Dolphins). Dolphins are very protective of each other, and they have killed sharks that were too close to their pod by repeatedly hitting them in the gills (Lockley 172). They will also try to save an injured or dead dolphin by keeping it at the surface for hours or even days (Lockley 19). Bottlenose dolphins are usually very friendly towards humans. Some wild dolphins even go into bays and interact with them (Dolphin Research Center). Dolphins also love to have fun. In captivity, they enjoy teasing each other and humans that are around their tanks (Lockley 48). In the wild, dolphins like to ride ocean waves or a boat’s stern or bow wake (Bottlenose Dolphins). They sometimes toss jellyfish and seaweed to one another and use plastic, seaweed, or other objects as â€Å"dolphin jewelry† on their fins, beaks, and necks (Cahill 93). Bottlenose dolphins truly are intriguing and individual animals. It’s hard to believe that some people actually hunt them. Beloved and admired by many, they should be protected in both captivity and the wild. Bottlenose dolphins have been entertaining people in for over eighty years, and hopefully they will continue to do so for many years to come.

Saras Secret Essay -- essays papers

Saras Secret Moving to the big city was a big step for Sara. Her parents always warned her about the dangers of city life, but she never let the warnings hinder her decision. Her dream of a fast paced life has been with her for as long as she could remember, and nothing could change her mind. Sara was brought up in a small town about 200 miles from the city. This was a town in which everyone was friends with everyone, and most of the doors where never locked. Looking at this town was like looking at a painting that would be hanging up in a museum somewhere. In fact, Sara's house looked like, it too, would have its own painting. Nothing was ever out of place, it even seemed as though each blade of grass knew that it had a particular position in which it need to stay, and the inside of their house was no different. Her parents where very protective over their only child. They always knew everything that went on in their daughter’s life; or so they thought. Sara kept something secret from her parents for as long as she could remember. Sara was born with something so different that she felt that if her parents ever found out, they wouldn't ever be able to accept it. After Sara graduated from high school she felt as though she needed to get out of the life she knew, and start over in a whole new environment. Convincing her parents that she should move to the city was the hardest part for her, but finally after months of constant debating, her parents finally gave in. But they never stopped telling her how they felt. Even as Sara was walking out to the moving truck with the last box, her parents told her that she was making a mistake and that only trouble is found in big cities. But Sara wasn’t listening, she knew that she was going to love her new life, trouble and all. Sara's apartment was on the small size but it didn’t seem to make a difference to her, she was finally on her own. She found a job at an accounting firm about a week after her arrival in the city. The tall building that her new job was in was a beautiful sight to her, and at that time she knew that she belonged there. Her new office was only about 6 blocks from her new home, so most of the time she walked to work. She would often stop to look up at the tall buildings, admiring how they seemed to look like those tall trees she once saw on a road trip with her parents.... ...purse back to the women, she took him by the wrists up to the street to the nearest police officer. She told the policeman what happened and then left wondering when she was going to get her reward. Sara then started to walk up the street, to catch her breath. When she reached the spot where she had heard the first women scream, the city froze, not by her doing, but by the spirit. Again, a faint light appeared from the manhole, and turned into a man’s face. Sara was excited that she was finally going to get what she had been working so hard for. And then the spirit started to speak, â€Å"You have done well Sara, you have saved the two people you needed to, to be able to receive your prize. But the thing is, you have already received it.† Sara didn’t quite understand, so the spirit went on, â€Å"You saved not one life, but the life of many. And you have risked a lot, so a lot is returned to you. The best reward is not of material value, but the feeling of value in yourself.† The spirit then vanished just like it had appeared. Sara then knew what the spirit had taught her. Sara decided to dedicate her life to saving others, and to only use her powers for the good of mankind.

Ideals and Values for 12th Century Medieval Aristocrats

Chrà ©tien de Troyes’ Lancelot: The Knight of the Cart, told a tale of a mighty knight. It has the air, to us, of fable. It was of fabrication as two cults of the time, courtly love and honor, dominated the story. These cults were parts of a set of medieval aristocratic ideals and values. Within this set, the cults had supportive notions of hospitality, oaths, service, and military prowess. Courtly love pushed the tale into existence when Lancelot stepped onto the cart and courtly love pushed the tale to completion with the death of Meleagant at the hands of Lancelot. Lancelot put into motion these actions. Lancelot’s love for Queen Guinevere bound him to honorable displays of his devotion to her.Chrà ©tien’s tale began with Meleagant’s appearance at King Arthur’s court at Camelot. He informed King Arthur that :â€Å"†¦King,If you have a single knightIn this court of yours you can trustTo take your queen to the woods,Where I’ll be goi ng when I’m finishedHere, then I’ll agreeTo let him have those prisonersI’ve got in my dungeons, providedHe can defeat me in battle,It being understoodThat possession of your queen is the prizeFor victory.†Ã¢â‚¬ ¦ (lines 69-80).Those at court did not immediately secure the return of the Queen. She was gone. Chrà ©tien soon related how a knight (Lancelot) jumped into a cart driven by a dwarf. Those having committed criminal or despicable acts occupied such a cart in those days. Lancelot entered the cart since the dwarf promised to later reveal the whereabouts of the Queen. Chrà ©tian noted :†¦and the knightFollowed along behindFor several steps, not climbingRight up. But his hesitant shameWas wrong. †¦(360-364).This delay on the part of Lancelot came back to thwart his efforts when he had gotten the release of the Queen from her captor. She said :â€Å"Indeed? Didn’t the cartShame you the least little bit?You must have hesitated,For you lingered a good two steps.And that, you see, was my soleReason for ignoring your presence.†Ã‚   (4491-4496).This rigidity characterized the cult of honor as exemplified by Lancelot’s actions. If an affair of honor came about, then the knight must perform in the honorable way. Yet there were levels of honor as when Meleagant, described as a pitiless brave fool, subscribed to a higher honor of battling Lancelot at King Arthur’s court in a year’s time and agreed to forgo combat at an earlier time (3886-3895).Chrà ©tien saw that honor in service to love ignored common sense and reason. Reason did not include in its realm the working of the heart. Love had its way. For love’s commands, even shame endured. Deep in reflection, Lancelot had no defense against love. He did completely forget himself. An opponent challenged Lancelot three times before crossing a stream. The opponent struck Lancelot with Lancelot still in love’s command. The opponent ha d unfairly struck him. Lancelot wanted to avenge this disturbance of his revery (891-893). Outside revery he was in a fair enough way but his one and only heart he entrusted to some one else such that he was constrained in a special manner (1231-1248).   He found the Queen’s comb. It had strands of her hair and he was ecstatic:Touching them a hundred thousandTimes, caressing with his eves,His lips, his forehead, his face.And all of it brings him happiness,Fills him with the richest delight;He presses it into his breast,Slips it between his shirtAnd his heart – worth more than a wagon-Load of emeralds or diamonds, (1470-1478).Later, in traversing the sword bridge, the blade cut so as to maim him but the suffering was sweet since love led him on and relieved his pain (3115-3122). Still later a distraught Lancelot, thinking that the Queen is dead, attempted to kill himself by hanging himself from his saddle by means of his belt (4264-4268).Honor had its greatest demands made upon it by love but it spanned also military activity for which the knights were constantly prepared. In this preparation, a generous hospitality aided them that mostly included horses (284-289), beds (458-463), and food. For the first two, they had a choice. The mistress of a house offered Lancelot the house and the mistress of the house (938-949).Thus prepared, their military valor was a pledge, an oath, which they must uphold. A knight could be in the grip of another knight and not fight correctly; so the second knight asked to release the first knight. Then the second knight could recover his military equipment and they could then fight in the approved manner (839-852). The more honor gained in combat, the better. Accompanying a damsel involved an unspoken oath and was a very serious business since the knight was then responsible for her.A challenging knight could assault her with impunity if a challenging knight defeated the escorting knight (1304-1322). Mercy could be gr anted for the about to be vanquished but this usually entailed an oath be taken. The one who granted mercy redeemed this oath to their benefit. If one had an oath to carry out, then could not do it, there could be shame of a great dimension when another knight did the deed (4013-4019). Knights sometimes honored a pledge, for honor’s sake, even though it seemed not in the best interests of most of those involved as when Kay sought to have the Queen accompany him into the forest where a knight awaited :The king was upset, but his wordHad been given, and he could not revoke it,No matter how angry and sorrowfulIt made him (which was easy to see).The queen, too, was deeplyDispleased, and the whole palaceDenounced Kay’s pride and presumptionIn making such a demand. (179-186).Again, it could be a combatant who would not continue the fight if pledged by his lady to cease. Then the other knight must not force a continuance then and there by striking the one who no longer lifts a weapon. Meleagant, for example, struck Lancelot.   The Queen had requested Lancelot to stop fighting:  The king came hurrying downFrom the tower, to stop him. StraightTo the field of battle he went,Speaking these words to his son:â€Å"What’s this? You think it’s fineTo go on fighting, afterHe’s stopped? You act like a savage!† (3824-3831).The truth of the matter is that Lancelot only appeared to give up. In truth he was doing what his lady had requested of him. Later her captors said she was lying about bloodied sheets (4788-4798). This was a most grievous charge and so combat was called for. Holy relics came out and, on their knees, the parties involved did swear. Truth in other matters was another preoccupation of the aristocrats that Chrà ©tien wrote about. There were standards of truth against which the knights and others could measure their conduct. To seek death in ignorance was the action of a fool.   A fool too was one who does not truly humble oneself. A fool never lost his folly. Those nobles, not fools, did not need to seek praise to enhance their deeds and self praise did not increase one’s esteem. The madness of a fool had no cure:â€Å"Who do you think believes you?†Said the king. â€Å"All these peopleCan tell for themselves what’s trueAnd False. We know you’re lying.† (3841-3844).Far from the fool was the man as lover who was always obedient and gladly did his lover’s bidding in short order. He knew much about love and included in this knowledge was that honor done for love entailed no shame. Should something greatly go amiss, he would not fear death. Death desired those who were afraid of it (4283-4284).Before death there were dwarfs. Lancelot encountered two dwarfs in the tale. Neither one was up to any good. The first, described as a â€Å"Low-born and disgusting† dwarf (353) did lead Lancelot astray. The dwarf lied as to knowing the Queen’s whereab outs but did convince Lancelot to enter the cart. The other dwarf encountered Lancelot on Lancelot’s approach to the water bridge. The dwarf promised to take Lancelot to a special place (5081-5084). This dwarf also lied.No one said anything about what happened to the dwarfs. Presumably, they received a suitable fate for their unbecoming behavior. Perhaps death found them soon enough without their heads. It seemed that beheading was the surefire way to ensure that the one on their way out did indeed depart. Lancelot did battle with an enemy and after having vanquished him, a woman wants the opponent’s head. Lancelot obliges :One swing of the sword, the headWas off, and it and the bodyFell to the ground. And the girlWas happy†¦.(2927-2930).The headless one wronged her. Lancelot had already showed mercy to the opponent. Then again the opponent had pleaded for mercy. Then too the opponent had been most impertinent with Lancelot. So the upshot of this battle was the da msel was pleased and the opponent lost his head.Another beheading occurred at the end of the tale. Meleagant reflected on how it was that Lancelot had made his way to Camelot. Meleagant had thought he had locked Lancelot in a tower from which there could be no escape. He realized that he was a victim of trickery. He was ready for something worse than great shame and humiliation (6967-6969).   In his battle with Lancelot he lost his right arm. He felt badly since he then could not strike Lancelot. Then he was smashed in the face by Lancelot. Three teeth are broken in his mouth. His state enraged him to the extent he could not speak and so did not seek mercy. Lancelot cut off his head. It was finished :And let me assure you, no oneWho was there, watching the battle,Felt the slightest pity.The king and his courtiers and ladiesWere fairly jumping for joy (7099-7103). Works CitedChrà ©tien de Troyes. Lancelot: The Knight of the Cart. Trans. Burton Raffel. New Haven & London: Yale Univ ersity Press ,1997.

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