Monsters

• Dinosaurs can be measured by length and height, but "biggest" usually means heaviest or bulkiest.

• Dinosaurs were not the biggest-ever living things on Earth--some trees are more than 100 times their size.

• The sauropod dinosaurs of the Late Jurassic were the biggest animals to walk on Earth, as far as we know.

• Sauropod dinosaurs may not have been the biggest animals ever. Today's great whales, and perhaps the massive, flippered sea reptiles called pliosaurs of the Dinosaur Age, rival them in size.

• For any dinosaur, enough fossils must be found for a panel of scientists to be sure it is a distinct type, so they can give it a scientific name. They must also be able to estimate its size. With some giant dinosaurs, not enough fossils have been found.

• Supersaurus remains found in Colorado, suggest a dinosaur similar to Diplodocus, but perhaps even longer, at 115ft (35m).

• Seismosaurus fossils found in 1991 in the U.S.A. may belong to a 130ft (40m) long sauropod.

• Ultrasaurus fossils found in South Korea suggest a dinosaur similar to Brachiosaurus, but smaller.

• Ultrasaurus fossils from the U.S.A. suggest a dinosaur similar to Brachiosaurus, but possibly even bigger.

• Argentinosaurus from South America may have weighed 100 tons or more.

By: Steve Parker, Dinosaurs