Dinosaurs roamed the Earth millions of years ago. Although people and dinosaurs did not exist on Earth at the same time, it’s possible to learn about these ancient animals by studying the remains they left behind. Fossils can be body fossils that include some remains of a plant or animal. Trace fossils might be a track or a footprint that shows that the animal or plant was present. The word “fossil” comes from the Latin word “fossus,” meaning “dug up.” Scientists have found fossils of dinosaur bones and teeth, which enable them to learn about how dinosaurs lived. A dinosaur that bit into something might have left a tooth mark, which could become a trace fossil. Scientists who find these bone and dental fossils can learn important information about dinosaurs.
Sauropods were large dinosaurs that ate plants. These herbivores lived around water, possibly spending some of their time in lakes and rivers. Sauropod dinosaurs include the Brachiosaurus, Plateosaurus, and Patagosaurus. These dinosaurs were large, and they often had smaller heads. Scientists have studied sauropod dental evidence to learn about their diet. This research has shown that sauropods actually had two different kinds of teeth designed both for eating coarse plants and for chewing plants that grew in the water.
- Introduction to Prosauropods
- Drexel Team Unveils Dreadnoughtus, a Gigantic, Exceptionally Complete Sauropod Dinosaur
- Sauropod Dinosaurs
- When Tyrannosaurus Chomped Sauropods
- Dinosaurs of South Dakota
The word “theropod” means “beast-footed.” Theropods walked on two feet, and they were usually carnivores. These meat-eating dinosaurs include the well-known Tyranosaurus Rex, Allosaurus, and Velociraptor. Theropod dinosaurs had very sharp, recurved teeth. These teeth were designed especially for tearing and eating meat. They also had sharp claws on their fingers and toes, which they used to attack their prey.
- Bird Evolution
- Weird Chilean Dinosaur Is Plant-Eating Theropod
- How Did Dinosaurs Behave?
- Dinosaurs Among Us?
- On the Loose: Fossils and Footprints
Stegosaurids walked on four legs, and they ate plants. A special characteristic of these dinosaurs was the rigid plates that ran along their backs and tails. Stegosaurids used these plates to protect themselves from enemies. Some scientists have guessed that the plates might have helped these dinosaurs keep cool in warm weather.
- Stegosaurus Dinosaur
- Stegosaurus Pictures
- Stegosaurus Stenops
- First Steps of a Baby Stegosaurus, Captured in 3-D
Hadrosaurs were special dinosaurs that lived near water. The teeth and bones of these creatures suggest that hadrosaurs were land animals, although they probably swam, too. With their webbed feet and a crest at the top of their heads, scientists have guessed that some hadrosaurs could breathe underwater with a type of snorkel. Other scientists think that hadrosaurs made trumpeting sounds out of their crests.
- Hadrosaur Dinosaurs
- Herd of Hadrosaurs in Denali: Insights on Large Herbivores in Warm Polar Region More Than 65 Million Years Ago
- First Occurrence of a Hadrosaur From the Matanuska Formation in the Talkeetna Mountains of South-Central Alaska
- New Answer for Why Hadrosaurs Showed So Much Skin
- Dancing With Dinosaurs
The dinosaurs with horns on their heads or faces were ceratopsians. These creatures also had frills at the backs of their heads. You might compare the head shape of ceratopsians with modern-day parrots. These horned dinosaurs had mouths full of flat teeth designed to grind up plants. Triceratops is one of the most well-known ceratopsian dinosaurs.
- Bunny-Size Dinosaur Was First of its Kind in America
- A Ceratopsian Dinosaur From China and the Early Evolution of Ceratopsia
- Meet Kelsey the Triceratops
- New Horned Dinosaur Reveals Evolution of Nose Horn in Triceratops Family
How Are Fossils Made?
Fossils can be formed in a variety of ways. The most common way an animal or a plant becomes fossilized is with a process called permineralization. When this happens, minerals fill in empty spaces and harden. This results in a hardened replica of the original animal or plant. Sometimes just a carbon impression of an animal or a plant is left behind on a rock. This type of fossilization is called carbonization.
How Are Fossils Dated?
Scientists work hard to learn the age of fossils. One way they can tell the age of a fossil is by the materials it contains. Specific materials break down at known rates, so this can help scientists guess about the age of fossils. Carbon-14 dating is a very accurate way to date fossils. Fossils older than 70,000 years old can’t be dated with carbon-14, though. Radiometric dating is another process that works for older fossils. This process measures the decay rate of isotopes present in the rocks around the fossils.
- Dating the Fossil Record
- Accuracy of Fossils and Dating Methods
- Determining the Age of Rocks and Fossils
- Dating Fossils and Rocks
- Rocks Provide a Timeline for Earth
- Dinosaur Activities
- All About Fossils
- Layers of Time
- Dig Into Dinosaurs
- Kid’s Guide to Dinosaur-Hunting in Northern Alberta
- Dinosaur Dynasty