As far as scientists can tell, all dinosaurs nested and laid eggs. From these eggs, their babies hatched. Hundreds of sites with fossil eggs of different dinosaurs have been found all over the world, including in the United States, France, Mongolia, China, Argentina, and India. The largest dinosaur egg fossil found is about 12 inches (30 centimeters) long and 10 inches (25 centimeters) wide, and may have weighed 15.5 pounds (7.0 kilograms). Scientists think the egg came from a giant, 100 million year old dinosaur called a Hypselosaurus. This is more than twice the size of the eggs of the modern African ostrich, which can lay eggs up to 6 inches (15 centimeters) long and 5 inches (13 centimeters) wide. The smallest fossilized egg found so far came from a Mussaurus; it measures about 1 inch (2.5 centimeters) long.

• What did dinosaurs use their teeth for?
• Would it hurt if a plant eating dinosaur bit you?
• What did dinosaurs eat?
• Which was the smallest dinosaur?
• What does the word dinosaur mean?
• Which was the biggest dinosaur?
• When did the dinosaurs live?
• What is the Sun made out of?
• When did the woolly mammoths live?
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• Have scientists ever discovered an entire animal fossil?
• What were the first animals to appear in water and on land?
• What were the first primitive plants to appear on land?
• What are fossils?
• Which country pollutes Earth the most?
• What is Earth Day?
• What is acid rain?
• Why is it important to conserve water?
• Why do stars twinkle?
• Why is it important to recycle?