Interesting facts to know about dinosaurs

News Delhi: Dinosaurs became extinct about 65 million years ago. During that period about 70% of all animal life on earth died out. Scientists call it a mass extinction – it wasn't the first mass extinction in earth's history and it probably won't be the last!We will probably never know exactly what happened butThere are many different theories about why this happened. Here are some claimed facts about Dinosaurs:1. Dinosaurs prospered for over 150 million years.Dinosaurs may have been the most successful creatures ever to colonize the earth.With our 100-year-max life spans, human beings aren't well adapted to understanding “deep time,” as geologists call it. Modern humans have only existed for a few hundred thousand years, and human civilization only got going about 10,000 years ago, mere blinks of the eye by Jurassic time scales. Everyone talks about how dramatically (and irrevocably) they went extinct, but judging by the immense amount of time they lasted.2. Dinosaurs weren't the first reptiles on earth.The first dinosaurs evolved in the middle to late Triassic period, about 230 million years ago. Before then, the dominant land reptiles were archosaurs (“ruling lizards”) and therapsids (“mammal-like reptiles”), and for 20 million or so years after the first dinosaurs appeared the most fearsome reptiles were crocodiles. It was only at the beginning of the Jurassic period, about 200 million years ago, that dinosaurs began their rise to dominance.3. There are species of dinosaurs that haven't been discovered yet.The only dinosaurs we can know about are the ones that leave fossil remains, but fossilization is an extremely rare process. Fossil evidence is abundant for late Jurassic (150 million years ago) and lateCretaceous (80-65 million years ago) dinosaurs, but long stretches of geologic time, across various continents, remain unaccounted for. 4. Most dinosaurs were vegetarians.Giant predators like Tyrannosaurus Rex and Giganotosaurus get all the press, but it's a fact of nature that the meat-eating “apex predators” of any given ecosystem are tiny in number compared to the plant-eating animals they prey on (which can rely on the vast amounts of vegetation needed to sustain such large populations). By analogy with modern habitats in Africa and Asia, herbivorous hadrosaurs, ornithopods and (to a lesser extent) sauropodsprobably roamed the Mesozoic Era in crowded herds, and were hunted by sparser packs of large, small and medium-sized theropods.5. The dinosaur kingdom is split into two main groups.paleontologists distinguished dinosaur into saurischian (“lizard-hipped”) and ornithischian (“bird-hipped”) dinosaurs. Saurischian dinosaurs include carnivorous theropods and herbivorous sauropods, while ornithischians account for the remainder of plant eaters, including hadrosaurs, ornithopods and ceratopsians, among others. Oddly enough, birds evolved from “lizard-hipped,” rather than “bird-hipped,” dinosaurs!6. Dinosaurs evolved into birds.There are bulk of the evidence points to modern birds having evolved from small, feathered, theropod dinosaurs during the late Jurassic and Cretaceous periods. Bear in mind, though, that this evolutionary process may have happened more than once, and that there were definitely some “dead ends” along the way (witness the feathered, four-wingedMicroraptor, which has left no living descendants).7. Dinosaurs lived at the same time as mammals.Many people mistakenly believe that mammals “succeeded” the dinosaurs 65 million years ago, appearing suddenly on the scene to occupy the ecological niches rendered vacant by theK/T Extinction. The fact is, though, that early mammals lived alongside dinosaurs (usually high up in trees, out of harm's way) for a large part of the Mesozoic Era. Most of these early furballs were about the size of mice, but a few (like the dinosaur-eating Repenomamus) grew to respectable sizes of 50 pounds or so, tiny by T. Rex standards but huge for an ancient mammal.