Did Sauropods Live?in?SwampsThe sauropod dinosaurs were the largest animals ever to live on land. They had?a?long neck and tail,?a?roundish body, and four stout legs. For many years,?it?was widely believed they must have spent most of their time?in?swamps, where their great bulk was buoyed up by water.?In?this way, they would have remained deeply submerged, breathing with only their nostrils poking out of the water. This idea may have originated as?a?consequence of the early nineteenth-century paleontologist?R.?Owen’s mistaken notion of the sauropod Cetiosaurus, which he thought to be an exceedingly large marine crocodile.?It?was later argued that sauropods were too big and heavy to have lived on land; that their legs would not have supported them; and that, like?a?whale, they needed the buoyancy of water to permit them to breathe.?It?was said that the long tails were used for swimming. Finally, it was suggested that the nostrils at the top of the skull were like the snorkel on?a?submarine, allowing the animal to breathe while remaining fully submerged (and presumably hidden and protected). Although as early as 1904 E.S. Riggs argued coherently that these animals were terrestrial, sauropods were persistently viewed as having?a?fully aquatic existence, with their bodies submerged?6?meters or more below the surface of the water and their necks craning to keep the nostrils just above the water’s surface.1.?The word “presumably”?in?the passage?is?closest?in?meaning toA. partially
B.?sufficientlyC.?safely
D.?most likely?2.??According to paragraph?1,?all of the following were generally believed about sauropods EXCEPT:A. Their bodies were too heavy for their legs to support them on dry land.
B. Their long tails helped them to swim.
C. They used their legs for support only when they were almost entirely submerged.D. They could breathe with only their nostrils above water.The idea of aquatic sauropods began unraveling in the 1950s and especially in the 1960s and 70s. In 1951, K. A. Kermack examined the consequences of water pressure on a submerged sauropod. The pressure on a body increases with the depth at which it is submerged.?■?If a sauropod was fully submerged, the chest – and hence the lungs?一?would have been under some 6 meters of water.?■?The pressure at this depth is nearly twice what it is at the surface and would tend to collapse the chest, pushing whatever air was in?the lungs up and out of the body.?■How a breath might be taken is hard to say, since the sauropod’s lungs would have to be expanded underwater; pushing outward against considerable pressure, a pressure opposing taking?a?breath that is greater than that encountered by any vertebrate living today.?■Unless sauropods had exceedingly powerful chest muscles, these animals certainly would not have been able to breathe in. For this reason, Kermack argued, it is perhaps better to envision sauropods as terrestrial animals.3.?Which of the sentences below best expresses the essential information?in?the highlighted sentence?in?the passage? Incorrect choices change the meaning?in?important ways or leave out essential information.A.??It is?hard to say how sauropods breathed while they were submerged because there are no vertebrates today that breathe at the same rate.B. Once sauropods forced air from their lungs, pushing it out against the considerable pressure of the water, it is hard to imagine?how they had strength to move underwater.C.?The sauropod’s lungs expanded under water?in?order to oppose the pressure from the surrounding water.D. It is?not clear that submerged sauropods could have breathed, since they would have had to overcome?a?pressure on the lungs greater than that encountered by any vertebrate today.?4.?In?paragraph?2,?why does the author remark?“Unless sauropods had exceedingly powerful chest muscles‘?
A. To explain how sauropods were able to survive the intense water pressure when submergedB.?To argue that aquatic sauropods must have had powerful chest musclesC.?To emphasize the unlikely conclusion under which sauropods could have breathed while submergedD.?To distinguish the requirements for breathing?in?while underwater from the requirements for breathing out while underwater??Sauropods climbed out of the water for good with Robert Bakker’s studies?in?the late 1960s and 1970s. This research emphasized the sturdy, pillar-like construction of the legs and feet of sauropods, surely strong enough for walking?一at least slowly?一on land. Additionally, Bakker pointed to the narrow, slab-sided thorax (chest)?一very unlike the amphibious hippopotamus but like rhinoceroses and elephants?一as evidence of terrestrial habits. Not since these studies have sauropods been thought of as submerged up to their nostrils.5. According to paragraph?3,?Bakker’s research supports which of the following statements about sauropods?
A. Their legs could support the full weight of their bodies.
B.?They had?a?thorax more like that of?a?rhinoceros than that of an elephant.
C. They used their sturdy, pillar-like legs to climb out of the water.
D.?They easily made the transition from underwater to terrestrial habits.6. The word “inviting” in the passage is closest in meaning toA. assumingB. strengtheningC. encouragingD. emphasizing?While for others, such as Brachiosaurus,?it?may have been true. While mounting?a?partial skeleton of Cetiosaurus at the Leicestershire Museums?in?England, J. Martin experimented with neck vertebrae to see what sort of restrictions there were on its range of motion, concluding that this sauropod was unable to upwardly flex its neck as far as had been thought previously. A dozen years after Marin’s work, Kent Stevens and Mike Parrish demonstrated?一using computer modeling?一that similar limitations are also found?in?Diplodocus and Apatosaurus. Their research, manipulation of?a?three-dimensional virtual model of the neck vertebrae, provided the feeding envelope (maximal vertical and horizontal range of head movement) of these two sauropods, again indicating that they generally browsed for vegetation within?2?or?3?meters of the ground.7.?What does the author mean by “again”?in?the remark “again indicating that they generally browsed for vegetation within?2?or?3?meters of the ground”?A. The computer models gave the same results about Diplodocus and Apatosaurus each time they were run.B.?The computer models showed that Diplodocus and Apatosaurus were like Cetiosaurus?in?having?a?limited range of motion?in?the neck.C.?The computer models showed that the neck vertebrae of Diplodocus and Apatosaurus were similar to the neck vertebrae of Brachiosaurus.D.?The computer models confirmed that sauropods had the same limited neck movements as giraffes.?8.?Paragraph?5?implies that Brachiosaurus differed from Cetiosaurus?in?which of the following respect?A. It could raise its neck higher.B. It was a plant eater.C. Its neck was longerD. It did not use its long neck to keep its head above water.?9. Look at the four squares [■?] that indicate where the following sentence could be added to the passage.Obviously, this would be fatal if the sauropod could not quickly refill its lungs with air.Where would the sentence best fit?10. Prose summaryThe sauropod dinosaurs had a long neck and tail and were the largest animals ever to live on land.Answer Choices:A. The function of sauropods’ long necks is not clear; in particular, sauropod species could not in general use their necks to feed like giraffes on treetops.B. Until the 1950s, sauropods were generally thought to have been aquatic animals that spent much of their time with only their heads above water.C. The ability of sauropods to move around both in water and on land caused early researchers to classify them as alligators.D. Because sauropods have a slab-sided thorax, Robert Bakker, and K. A. Kermack argued that sauropods would not have been able to expand their lungs when they were submerged.E. Computer models of the vertebrae of sauropod necks show that probably only Brachiosaurus was able to raise its neck about 2 or 3 meters.F. In view of arguments that sauropods had legs that could support their weight and probably could not have breathed with their bodies submerged, it is now accepted that sauropods were land dwellers.