How the Dinosaurs Got Back their Good Posture 





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How the Dinosaurs Got Back their Good Posture



 

Suppose you were a brontosaur. Would k3you want to live your whole life in a muddy swamp up to your armpits in water? You'd have prune skin all year around.

Or suppose you were a Stegosaur or a Triceratops. Would you want to crouch awkwardly on the ground with your elbows bent outward like a crocodile? Your stomach would scrape the dirt.

Maybe the plastic dinosaur models you've seen are shaped like that, but dinosaurs themselves had much better posture. They didn't waddlesluggishly along the ground. They stood straight and ran and leaped and reared upon two legs. A brontosaur didn't need water to support its weight. It raced across dry plains, its huge tail whipping behind it.

When the first complete dinosaur skeletons were dug up in the middle 1800s, early paleontolo­gists suspected that dinosaurs had good posture. O.C. Marsh of Yale University restored a Triceratops skeleton that stood upright on straight legs, as a rhinoceros does today. Others believed that the brontosaurs and Stegosaurus could rear up on their hind legs and tail to nibble the tender leaves at the tops of trees.

These early scientists saw a strong likeness between dinosaurs and warm-bloodedbirds. In 1870 Thomas Huxley told the Geological Soci­ety of London his theory that birds were direct descendants of dinosaurs. He demonstrated simi­larities in ankle joints, hipbones, hind foot place­ment, and other features, His ideas were widely accepted.

But in the 1920s and 1930s paleontologists rejected Huxley's earlier ideas. Instead of thinking of dinosaurs as brisk, energetic animals, these scientists pictured them as dull reptiles plodding through prehistory toward certain extinction. So when dinosaur skeletons were reconstructed, they were forced into the contorted posture or rep­tiles.

Opinions began to change back in the 1960s when modern paleontologists studied dinosaurs from a number of different scientific view-points. They combined their findings to reconstruct the lively, erect dinosaurs that nineteenth-century pa­leontologists had imagined.

Footprints,for instance, told paleontologists that dinosaurs ran quickly. Based on knowledge about modern animals and their footprints, British scientist McNeil Alexander figured out a way to calculate speed from stride length and footprint size. So when the American James Farlow studied some fossil tracks in 1981, he could deduce from them that dinosaurs ran as fast as twenty-five miles per hour.

Footprints also suggested that four-legged dinosaurs stood and walked on straight legs. If a dinosaur walked like a crocodile, with its el­bows and knees bent outward, its footprints would be spread in a wide pattern on either side of its body. But dinosaur footprints were placed close together, directly underneaththe body. That pattern could only occur if dinosaurs had walked upright like elephants.

Paleontologists used biology to confirm that dinosaur stood upright. In 1971 Robert Bakker of the University of Colorado studied the shoulderanatomy of the Triceratops. If a Triceratops had the hunched-down posture of a reptile, its shoul­der joints should be similar to the joints of reptiles, such as crocodiles. Bakker demonstrated that the shoulder of a Triceratops was completely dif­ferent. A crocodile's joint is loose so that the shoulder bone can rotate easily within it. This allows its front legs to spread outward. But the Triceratops had a snug socket that gripped the shoulder bone in an upright posture.

Paleontologists tried to show the differences between quick-moving dinosaurs and the slower reptiles in other ways, too. If a dinosaur was able to run and be active, it needed a large heart. Modern reptiles have small hearts and small chests to contain them. Most dinosaurs, however, had very large chests designed to contain a huge heart.

It was even demonstrated that some dinosaurs were built to rear up to a standing position where they balanced on their hind legs and tail. Stegosaurus had long spines on its backbone at the hips. These were attached to strong ligaments running up its back so that the Stegosaurus could easily push itself up on two legs. The tail bones were made to hold strong tail muscles that would support the standing dinosaur. Brontosaurs had the same skeletal construction along their backbone. At feeding time these dinosaurs would rear up to eat the tops of trees.

Paleontologists continue to explore surprising theories about dinosaurs, and their findings ten us many exciting things about the way dinosaurs lived. Modern science now supports the idea that dinosaurs really did have the good posture that the first paleontologists believed they had. Thanks to imaginative paleontologists, we can picturebrontosaurs and Triceratops and the other di­nosaurs running and leaping around energeti­cally.

Modern paleontology has given dinosaurs a future. Sir Richard Owen invented the term Dinosauria in 1842, but in the 1920s it fell out of useas a scientific classification. Instead, di­nosaurs became a subdivision of Class Reptilia. In 1972 Robert Bakker and English paleontologist Peter Galton brought back Class Dinosauria. Later they went one step further. They agreed with Thomas Huxley's 1870 conclusion and made Class Aves (birds) a subdivision of Class Dinosauria. This means that dinosaurs are no longer extinct. They live onin the birds that soar above us.

(From’ Cricket’ by Elaine Marie Alphin)

Common Sense About Smoking

It is often said, 'I know all about the risk to my health, but I think that the risk is worth it.' When this statement is true it should be accepted.

Everyone has the right to choose what risks they take, however great they may be. However, often the statement really means, ‘’I have a nasty feeling that smoking is bad for my health, but I would rather not think about it’’. With some of these people the bluff canbe called and they can be asked to explain what they think the risk to their own health is. When this is done few get very far in personal terms. The bare fact that 23,000 people died of lung cancer last year in Great Britain often fails to impress an individual. When it is explained that this is the equivalent of one every twenty-five minutes or is four times as many as those killed on the roads, the sig­nificance is more apparent. The one-in-eight risk of dying of lung cancer forthe man who smokes twenty-five or more cigarettes a day may be better appreciated if an analogy is used. If, when you boarded a plane, the girl at the top of the steps were to welcome you aboard with the greeting, '’I am pleased that you are coming with us - only one in eight of our planes crashes,'’ how many would think again, and make other arrangements? Alternatively, the analogy of Russian Roulette may appeal. The man smoking twenty-five or more a day runs the same risk between the ages of thirty and sixty as another who buys a re­volver with 250 chambersand inserts one live bullet and on each of his birthdays spins the chamber, points the revolver at his head, and pulls the trigger. One of the difficulties in im­pressing these facts on people, is that, despite the current epidemic of lung cancer, because it is a disease which kills relatively quickly, there are many who have as yet no experience of it among their family or friends.

( by Christopher Wood )

 

 

Silver Blaze

 

In Devon, a valuable racehorse, Silver Blaze, had disap­peared; its trainer, John Straker, was found dead.

Silver Blaze was ready to run in an important race in a few days' time. On the night he disappeared, a stable-boy was guard­ing him. The boy had a dog with him, and two other boys were sleeping above the stable

A girl who was taking the boy his supper saw a stranger near the stables. She ran back to the house to get help, and the stranger ran away. The stable-boy said that the stranger had asked him, "Will Silver Blaze really win the race?" The boy said he hadn't opened the stable door.

At about midnight, John Straker, the horse's trainer, told his wife he was still worried about the horse. He went out, to­wards the stables, taking a sharp doctor's knife with him.

The next morning, the stable door was opened. The horse had gone, and the stable-boy was unconscious. Opium was found in his food. Usually, you can taste opium, but he had strong meat for supper, and that had hidden the taste.

John Straker was found out on Dartmoor. He was dead, his head crushed. His coat was hanging over a bush. Near him was his knife, and a scarf which was recognized as the stranger's.

The police found and arrested the stranger, Mr. Simpson. They said he had drugged the boy, stolen the horse and killed Straker. Simpson denied it all, and they still didn't know where the horse was.

Colonel Ross, the horse's owner, then sent a telegram to Sherlock Holmes, asking him to find the horse. Holmes and his friend, Dr. Watson, were at their flat in Baker Street, in London. They had read the whole story in the newspapers. Holmes took no notice of the telegram, saying that Silver Blaze was somewhere on Dartmoor, and would soon be found.

Two days later, Holmes understood he was mistaken, and he and Dr. Watson took a train to Tavistock, in Devon. They went to the place on Dartmoor where Straker's body was found. There, Holmes found a match. Then they searched the place, and finally found the tracks of Silver Blaze. Some of the prints were alone, pointing towards Colonel Ross's stables; others had the footprints of a man with them, and pointed towards another stable.

Holmes and Watson talked to the owner there, and he final­ly admitted that he had stolen Silver Blaze, taken him home and hidden him. He wanted his own horse to win the race. He said he knew nothing about the murder.

Now, said Dr. Watson, the mystery was over. The police had found the murderer, and they had found the horse. Sherlock Holmes didn't agree. When they went back to Colonel Ross's stables, Holmes asked, "Was there anything wrong with any animals on the farm?" A farm-worker said that three of the sheep had gone lame.

If Simpson, the stranger, had drugged the stable-boy, he was very lucky. He couldn't know that there was meat for sup­per. And how did he put the drug in the food?

The two boys sleeping hadn't woken up. So the dog hadn't barked. So the dog knew the thief.

Who carries a doctor's knife for self-defense? A knife like that is for something different—like making a horse lame.

Someone who isn't a doctor would have to practice an oper­ation of a horse's leg—perhaps he would practise on some sheep.

A man who hangs his coat on a bush, and strikes a match, doesn't run after thieves. He's going to do something difficult; like operating on a horse.

The scarf? Straker must have found it near the stables, and decided to tie the horse's legs with it. Silver Blaze became frigh­tened, kicked back, and killed Straker.

Why would Straker want to lame a horse which he trained? Because he had bet money on another horse.

Elementary, my dear Watson!

( after Conan Doyle )

The Speckled Band

 

Helen's Story

At the time of this story I was still living at my friend Sherlock Holmes's flat in Baker Street 221B in London.

Very early one morning, a young woman, dressed in black, came to see us.

She looked tired and unhappy. "Please, help me, Mr. Holmes!" she cried. "I'm afraid! Afraid of death!"

"Don't worry, Miss. Just sit down and tell us your story", said Holmes kindly.

"My name is Helen Stoner", she began. "I live with my stepfather, Dr Grimesby Roylott, near a village in the country. He was poor when he married my mother. It was in India. My sister Julia and I were very young then. Our father was dead, you see."

"Your mother had some money, perhaps?" asked Sherlock Holmes.

"Oh, yes, mum had a lot of money, so my stepfather wasn't poor anymore."

"Tell me more about him, Miss Stoner," said Holmes.

"Well, he's a violent man.

In India he once killed his Indian servant and got to prison. Then we all came back to England.

Mother died in an accident eight years ago. So my stepfather got all her money, but if Julia or I marry, he must pay us 250 every year."

"Well, go on, Ms Stoner", said Holmes. "Now you live with him in the country..."

"Yes, but he stays at home and never visits anybody. He's more and more violent now. Everybody is afraid of him and his wild Indian animals which run freely around the garden. A friend sends them to him from India.

Besides, my stepfather likes wild people, and gypsies can come and go when they like. Poor Julia and I had very unhappy lives. We had no servants. They always left because they were afraid of my stepfather, and we had to do all the work in the house. Julia was only thirty when she died..."

"When did she die?" asked Sherlock Holmes.

"Two years ago, and that's why Fm here. We never met anybody in the country, but sometimes we visited some of my family who live near London. There Julia met a young roan who asked to marry her. My stepfather agreed, but soon after this she died." Miss Stoner put her hand over her eyes and cried for a minute.

"Tell me everything about her death", Holmes said.

"It was a terrible time!' she answered. "Our three bedrooms are all downstairs. First there is my stepfather's room. Julia's room is next to his, and my room is next to Julia's. The rooms ail have windows on the garden side of the house, and doors which open into the corridor. One evening our stepfather was smoking his strong Indian cigarettes in his room. Julia couldn't sleep because she could smell them in her room, so she came into my room to talk to me. Before she went back to bed, she said to me, "Helen, have you ever heard a whistle (cbhct) in the middle of the night?"

I was surprised. "No," I said. "It's strange," she said. "Sometimes I hear a whistle, but I don't know where it comes from. Why don't you hear it?"

I laughed and said, "I sleep better than you do." So Julia went to her room, and locked the door after her."

"Why did you lock your doors?’’ asked Sherlock Holmes.

" We were afraid of the wild animals and the gypsies,' she answered.

"Please go on/'said Holmes.

"I couldn't sleep that night. It was a very stormy night, with a lot of wind and rain. Suddenly I heard a woman's scream (dorm). It was my sister's voice. I ran into the corridor, and just then I heard a whistle, and a minute later the sound of falling metal. I didn't know what it was.

I ran to my sister's door. She opened it and fell to the ground. Her face was white and afraid, and she was crying, "Help me, help me, Helen, I'm dying!" and she cried out: "Helen! Oh my God, Helen! It was the band! The speckled band!"

She wanted to say more, but she couldn't. I called my stepfather, who tried to help her, but we could do nothing. And so my dear sister died.'

'’Are you sure about the whistle and the sound of falling metal?" asked Holmes.

" I think so," answered Helen. "But it was a very stormy night. Perhaps I made a mistake. The police couldn't understand why my sister died. Her door was locked and nobody could get into her room. They didn't find any poison in her body And what was ‘’the speckled band"? Gypsies wear something like that round their necks.

I think she died because she was so afraid, but I don't know what she was afraid of. Perhaps it was the gypsies. What do you think, Mr. Holmes?'

Holmes thought for a minute. "Hmm," he said. "That is a difficult question. But please go on."

"That was two years ago'' Helen Stonier said. "I have been very lonely without my sister, but a month ago a dear friend asked me to marry him. My stepfather has agreed, and so we're going to marry soon. But two days ago I had to move to my sister's old bedroom, because some men are mending my bedroom wall, and last night I heard that whistle again!

I ran out of the house immediately and came to London to ask for your help. Please help me, Mr. Holmes! I don't want to die like Julia!"

"We must move fast," said Holmes. 'If we go to your house today, can we look at these rooms? But your stepfather must not know.’’

"He's in London today, so he won't see you. Oh thank you, Mr. Holmes, I feel better already."

 

( By Arthur Conan Doyle )

The Speckled Band





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