Although dinosaur remains are few, we know or can deduce quite a lot from their fossilized skeletons. For example, we can calculate a dinosaur’s weight by studying its bones. Heavy animals have massive bones to support their weight, while swift-moving hunters usually have very light, hollow bones. Muscles are firmly attached to bones, and although no trace of the muscles remains in fossils, the attachment points can be seen on the bones. These tell scientists how big the muscles must have been.
We know that a bulky digestive system is necessary to digest vegetable matter. The herbivores would have had massive barrel-shaped bodies, while carnivores would be slimmer. The shape of the teeth tells us what type of food the dinosaur ate.
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