What was the biggest dinosaur? What was the smallest?

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Welcome to CoreFacts, where we're always short on time and big on science. I'm Danielle Eganhouse. Today's question goes back to the Dinosaur ages.

What was the biggest dinosaur? What was the smallest?

The largest complete dinosaur we know of was Brachiosaurus; it reached 23 m in length and 12 m in height (about the length of two large school buses and the height of a four-story building). Fragmentary leg bones and vertebrae of even larger dinosaur species are known, but these skeletal remains are too incomplete to determine their exact size. Several of these might have been one and a half to two times larger than Brachiosaurus. The smallest dinosaurs were just slightly larger than a chicken; Compsognathus  was 1 m long and probably weighed about 2.5 kg (about 6.5 lb). These three dinosaur types all lived during the Jurassic Period. Mussaurus was claimed as the smallest dinosaur, but it is now known to be the hatchling of a dinosaur type that was much larger than Compsognathus when fully grown.

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