One: What is a dinosaur?
Two: When did the dinosaurs first appear? What's the oldest dinosaur?
Three: Where did the dinosaurs live?
Four: How many types of dinosaurs are there?
Five: How long could dinosaurs live?
Six: Which was the smallest dinosaur? Largest?
Seven: What did dinosaurs eat?
Eight: Did dinosaurs communicate?
Nine: What colors were the dinosaurs?
Ten: How are dinosaurs named?
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A: A dinosaur was any of a group (Dinosauria) of extinct chiefly terrestrial carnivorous or herbivorous reptiles of the Mesozoic era. It is generally accepted that to be classified as a dinosaur, an animal must have lived during the Mesozoic era, had an upright posture in which the legs come straight down from the body, bird or lizard-like hips, extra openings in the skull, and lived and moved on land.
A: The oldest dinosaur types are known
from rocks in Argentina and Brazil. They are about 230 million years
old. The oldest dinosaur found thus far is Eoraptor, a small meat-eating
dinosaur. Most paleontologists believe older dinosaurs may yet be found.
A: Paleontologists have evidence that dinosaurs lived on all of the continents. During the Triassic Period (230 million years ago) the continents were arranged together as a single supercontinent called Pangea. Over the 165 million years of dinosaur existence Pangea slowly broke apart and spread bringing the dinosaurs with it.
A: About 700 species of dinosaurs have been named. A recent scientific review, however, suggests that only about one half of these are based on fairly complete specimens that can be shown to be separate species. These species are placed in about 300 valid dinosaur genera (Stegosaurus, Diplodocus, etc.), although about 540 have been named. Recent estimates suggest that about 700 to 900 more dinosaur genera may remain to be discovered.
A: Dinosaur lifespans probably varied in length from tens of years to hundreds of years. Most scientific estimates are between 50 and 300 years.
A: The smallest dinosaurs were just slightly larger than a chicken. Compsognathus was 1 m (3 ft) long and weighed about 2.5 kg (about 6.5 lb). The largest complete dinosaur we know was Brachiosaurus It was 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).
A: Dinosaurs that are classified as herbivores
ate plants (but not grass, which hadn't evolved yet). Many of these
plants had edible leaves, including evergreen conifers (pine trees,
redwoods, and their relatives), ferns, mosses, horsetail rushes, cycads,
ginkos, and in the latter part of the dinosaur age flowering (fruiting)
plants. Although the exact time of origin for flowering plants is still
uncertain, the last of the dinosaurs certainly had fruit available to
eat. The dinosaurs classified as carnivores ate lizards, turtles, eggs,
or early mammals. Some hunted other dinosaurs or scavenged dead animals.
A: Dinosaurs most likely communicated both vocally and visually. Some dinosaurs such as Parasaurolophus and Corythosaurus had chambered headcrests which could have been used to amplify grunts or bellows.
A: Although definite skin color is unknown,
paleontologists think that some dinosaurs likely had protective coloration,
such as pale undersides to reduce shadows, irregular color patterns
("camouflage") to make them less visible in vegetation, and so on. Those
dinosaurs that had enough armor, such as the stegosaurs and ceratopsians,
may not have needed protective coloration, and may have been brightly
colored as a warning to predators. Most believe dinosaurs probably were
most likely brightly colored as modern lizards, snakes, or birds.
A: Dinosaurs are generally named after a physical characteristic, the place they were found, or a person involved in the discovery. Usually the name consists of two Greek or Latin words (or combinations); in order, these are the genus (plural, genera) and the species name.