nging to what appeared to be a lizard of enormous size. He named his find Megalosaurus which means "Great Lizard." Though Buckland was not the first person to find a Megalosaurus bone (Robert Plot described one as far back as 1676) he was the first to realize that these fossils belonged to an unknown class of huge reptiles. These huge lizards fired the imagination of 19th century scientists and the general public alike. People marveled at the drawings made from their early study of dinosaur fossils. Scientists fought over excavation sites so they could be the first to discover and name new species. (c) The question of whether dinosaurs were warm-blooded, like mammals and birds, or cold-blooded, like reptiles and fish, has been debated since dinosaur fossils were first discovered in 1825. Cold-blooded, or ectothermic, animal's bodies stay about the same temperature as the environment around them. This means cold-blooded animals tend to be sluggish in cool weather. In the morning a lizard must sun itself on a rock to warm up before it can take on any vigorous activity. Warm-blooded, or endothermic, animals generate their own heat and maintain a nearly constant temperature no matter what conditions are like outside the body. This means that an animal, like a dog, can be active in even freezing weather.(d) One of the great mysteries in science is the extinction of the dinosaurs at the end of the Mesozoic Era some 65 million years ago. Who (or more likely what) caused it is unknown and a subject of great debate. Scientists believe that climatic changes might be responsible for most of these extinctions. There is evidence that shows the temperature dropped at the end of the Mesozoic and the sea levels fell. A sudden change in climate might affect the growth of plants and the dinosaur's food supply. Some of the theories of dinosaur extinction are: -Cosmic radiation from a nearby exploding supernova star killed them. -Acid rain from volcano act...
