广东佛山公务员考试网:恐龙资料(英文)
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dinosaur
Any of various extinct, often gigantic, carnivorous or herbivorous reptiles of the orders Saurischia and Ornithischia that were chiefly terrestrial and existed during the Mesozoic era.
恐龙:一种主要生活在中生代时期的陆栖动物,是庞大的食肉或食草爬行类动物,属龙盘目与鸟盘目,已绝种
详细资料:
Fossil remains of dinosaurs have been found in rock strata of every continent, indicating that they differed widely in structure, habitat, and diet. Their brain sizes varied, with some predators having brain-to-body ratios equivalent to those of some modern birds and animals. Many species built nests. Many theories regarding dinosaurs and their behavior are hotly debated by the experts. These include the debate over the grouping of birds with dinosaurs, the question of whether nonavian dinosaurs were cold-blooded (ectothermic) or warm-blooded (endothermic), the question of whether dinosaurs protected and nurtured their young in the nest after hatching or whether the young were mobile and self-sufficient at birth, and the reason for the disappearance of nonavian dinosaurs.
No complete fossil dinosaur has ever been discovered. Inferences must be made from fragments or pieces that have been compressed and distorted. Information about the diet has been gleaned from stomach contents and coprolites (fossilized dinosaur feces) and by comparing the teeth to those of living animals, for example, relating the large grinding teeth of hadrosaurs to those of living herbivores. Fossilized dinosaur footprints, such as the trackways found at Davenport Ranch in Texas, have been interpreted as evidence that dinosaurs traveled in herds. What is known about dinosaurs is that, far from being evolutionary failures, they dominated their habitats for most of their 160 million years of existence (the human species Homo sapiens has existed for approximately 150,000-200,000 years).
Although all dinosaurs were originally classified in a single order, it was later discovered that the group contained two distinct types distinguished by structural differences. The pelvis in the saurischian (lizard-hipped) dinosaurs resembles that of still-extant reptiles, but in the ornithischian (bird-hipped) dinosaurs the pubic bone of the pelvis has forward and backward extensions that resemble those found in birds. It was later determined, however, that the backward-tilting hips of ornithischian dinosaurs and birds were the result of convergent evolution and not inheritance. Many other shared characteristics have been noted between birds and saurischians, and it is now believed by many paleontologists that modern birds are in fact extant dinosaurs of the saurischian order.
The jaws and teeth of the two dinosaur orders also differ. The saurischian order, which includes both herbivores and carnivores, has teeth around the entire jaw or confined to the front of the mouth. Ornithischians have “cheek teeth” along the sides of the jaw, but never in the front; the bones at the front of the mouth sometimes developed into the horny beaks typical of modern turtles. All known ornithischians were herbivores.
Dinosaurs are further classified into some common groupings. In the saurischian dinosaurs, some were theropods [Gr., = beast feet], a group sharing hind feet with only three functional toes (e.g., the carnivorous bipeds Tyrannosaurus , Velociraptor , Deinonychus , and possibly the living birds); others were sauropods [Gr., = lizard feet] with small heads and long necks (e.g., the herbivorous quadrupeds Apatosaurus [Brontosaurus] and Diplodocus ). Among the ornithischians, there were ornithopods (bird-footed dinosaurs), such as Iguanodon ; thyreophorans (armored dinosaurs), such as Stegosaurus and Ankylosaurus ; and ceratopsians (horned dinosaurs), such as Triceratops . The total number of dinosaur genera that existed is unknown; new species are discovered every year, but some species, on further examination, are found to be redundant with earlier finds. One estimate of the possible number of distinct genera exceeds 1,800.
Similarities of dinosaurs found on what are now different continents have given scientists clues to the breakup of the supercontinent Pangaea, which began about 170 million years ago. For example, the discovery of a 130-million-year-old African dinosaur similar to the North American Allosaurus suggests that the African plate was connected to the northern continents (Laurasia) longer than had been believed previously.
Dinosaurs were reptiles and most dinosaurs hatched from eggs. Amazingly blue whales are bigger than any dinosaur found so far. The largest dinosaurs were over 100 feet long and up to 50 feet tall. The smallest dinosaurs, were about the size of a chicken.
No one knows exactly what noises dinosaurs made, what color they were or even when they lived. But scientist do have theories on these topics and you can find some of this information in our links.
Most dinosaurs were plant-eaters (herbivores) about 65% of them. Some dinosaurs were meat-eaters (carnivores). Dinosaurs had many different distinguishing features that you can read more about when reading facts on each dinosaur.
No one really knows exactly how many dinosaur species exist. The estimates vary from between 250 to over 1300 species.
The term dinosaur (terrible lizard) was coined by the English anatomist Sir Richard Owen in 1842.
No one knows how the dinosaurs became extinct or even if they are extinct, but there are many interesting theories on the topic and you can read more about them from our links page.
dinosaur
Any of various extinct, often gigantic, carnivorous or herbivorous reptiles of the orders Saurischia and Ornithischia that were chiefly terrestrial and existed during the Mesozoic era.
恐龙:一种主要生活在中生代时期的陆栖动物,是庞大的食肉或食草爬行类动物,属龙盘目与鸟盘目,已绝种
Millions of years ago, long before there were any people, there were dinosaurs. Dinosaurs were one of several kinds of prehistoric reptiles that lived during the Mesozoic Era, the "Age of Reptiles."
Dinosaurs were reptiles and most hatched from eggs. No dinosaurs could fly and none lived in the water.
The largest dinosaurs were over 100 feet (30 m) long and up to 50 feet (15 m) tall (like Argentinosaurus, Seismosaurus, Ultrasauros, Brachiosaurus, and Supersaurus). The smallest dinosaurs, like Compsognathus, were about the size of a chicken. Most dinosaurs were in-between.
It is very difficult to figure out how the dinosaurs sounded, how they behaved, how they mated, what color they were, or even how to tell whether a fossil was male or female.
There were lots of different kinds of dinosaurs that lived at different times.
Some walked on two legs (they were bipedal), some walked on four (they were quadrupedal). Some could do both.
Some were speedy (like Velociraptor), and some were slow and lumbering (like Ankylosaurus).
Some were armor-plated, some had horns, crests, spikes, or frills.
Some had thick, bumpy skin, and some even had primitive feathers.
Most dinosaurs were plant-eaters (also called herbivores). For example, Triceratops was a plant-eating dinosaur
Some dinosaurs were meat-eaters (also called carnivores). For example, T. rex was a meat-eating dinosaur.
The dinosaurs dominated the Earth for over 165 million years during the Mesozoic Era, but mysteriously went extinct 65 million years ago. Paleontologists study their fossil remains to learn about the amazing prehistoric world of dinosaurs.
When the dinosaurs lived, the Earth's continents were jammed together into a supercontinent called Pangaea and the Earth was warmer than it is now.
恐龙dinosaur
恐龙的dinosaurian
恐龙般大的dinosauric
同意驼铃牧场