English

恐龍，是對一些史前爬行動物的統稱。最早出現於大約2億2千萬年以前，生活於三疊紀、侏羅紀和白堊紀，存在了1億5千萬年。在大約六千5百萬年前的白堊紀晚期，幾乎所有種類的恐龍都滅絕了，但是有一種觀點認為，現代鳥類與某種恐龍有血緣關係。

恐龍(Dinosauria)這名字最早為英國科學家理察·歐文(Richard Owen)在1842年提出。它由希臘辭彙deinos(意為「恐怖的」或「極其巨大的」)和sauros(意為「蜥蜴」)組成。恐龍一詞為日本翻譯，後為中國引用。

恐龍的體型差異很大。已知最小的恐龍只有雞那麼大（鼠龍(Mussaurus)，其幼體僅有20公分），但大多數都體型巨大。最大的是蜥腳亞目恐龍（戈壁卡拉麥裡龍(Klamelisaurus gobiensis)，體長超過30公尺，高10公尺），為曾經存在過的最大的陸生生物，在所有生物中，僅次於鯨。

許多其他種類的爬行生物與恐龍生活在同一時代。某些種類同樣體型巨大，外形奇異，但它們不是恐龍。如蛇頸龍。

恐龍消失於六千5百萬年前的白堊紀-第三紀滅絕事件（Cretaceous-Tertiary extinction event）。通常的解釋是一顆巨大的隕石撞擊地球造成了滅絕（最早為Walter Alvarez提出）。但這一理論尚有爭議。

一般隕石的說法乃指隕石撞擊地球後，大量的灰塵暴淹沒大地及大氣，造成陽光無法直接照射到地球表面，各地氣溫逐漸寒冷，恐龍因無法在冷酷的氣候中生存及覓食，而死亡變成化石。另有一說法，指當時地球兩極因氣溫的急劇變化，造成海面水位上升，造成大陸與大陸間有河流阻隔，造成恐龍覓食困難而死亡。
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The dinosaur, is to some prehistoric reptile's general designation. Appears most early before about 220,000,000 years, lives in the Triassic period, the Jurassic Period and the cretaceous p
eriod, has existed for 150,000,000 years. In about 65,000,000 year ago cretaceous period later periods, the nearly all type dinosaur all extinguished , but had one viewpoint to believe, the modern birds had the blood relationship relations with some kind of dinosaur.
Dinosaur (Dinosauria) this name most early observed · Irving for the English scientist principle (Richard Owen) to propose in 1842. It (Italy is “terror” or “extremely huge”) and sauros (Italy is “lizard”) is composed by Greek vocabulary deinos. A dinosaur word translates for Japan, latter quotes for China.
Dinosaur's build difference is very big. The known smallest dinosaur only then the chicken is so big (mouse dragon (Mussaurus), its young animal only has 20 centimeters), but the majority build are all huge. Biggest was the sauropoda dinosaur (in the Gobi Kara wheat the dragon (Klamelisaurus gobiensis), body long surpasses 30 meters, height 10 meters), for has existed the biggest land lives the biology, in all biology, is only inferior to the whale.
Many other type crawling biology and dinosaur life in identical time. Certain type similar build is huge, contour strange, but they are not the dinosaur. If plesiosaurus.
The dinosaur vanishes in 65,000,000 year ago cretaceous period - tertiary period extinguishes the event (Cretaceous-Tertiary extinction event). The usual explanation was a giant meteorite hit Earth creates extinguished(is most early Walter Alvarez proposes). But this theory Shang You disputed.
After the common meteorolite view is refers to the meteorite hit Earth, the massive ash dust storm submergence earth and the atmosphere, create the sunlight to be unable the direct radiation to the earth's surface, each place temperature is cold gradually, because the dinosaur is unable in the callous climate to survive and to look for food, but died turns the fossil. And some view, referred to at that time the terrestrial pole because of the temperature rapid change, created the sea level water level rise, created between the mainland and the mainland has the rivers impediment, created the dinosaur to look for food to die difficultly.

Generally it was said there is not enough food for them on earth, so they kill each other.