Dinosaurs are the largest animal that has ever existed on land, though an Argentine dinosaur is the biggest ever discovered because it is as heavy as a Boeing 737(American Airplane). The behemoth weighed more than 65 tons and perhaps as many as 77 tons and 120 feet long. That makes the animal not just the biggest known dinosaur but also the biggest known land animal ever. Only a few whale species are heftier.
Definitely, in terms of mass, Earth’s largest mammal is the blue whale (Balaenoptera musculus). Weighing approximately 136 metric tons (150 tons) and growing to a length of more than 30 meters (98 feet), it is also the largest animal that ever lived on Earth (Both on land & in water). But growing conditions are different in the ocean.
Today the elephant holds the title, but if we reach back into history, we can find even larger creatures. Many of the dinosaurs of the Mesozoic Era (about 252 million to 66 million years ago) were longer and more massive than modern elephants, hippopotamuses, and rhinoceroses. The largest dinosaurs of the era were the sauropods, species of the Argentine dinosaur & a collection of four-legged herbivorous species that possessed long necks and tails.
Basic Dinosaur Facts
Dinosaurs are a group of reptiles that have lived on Earth for about 245 million years.
In 1842, the English naturalist Sir Richard Owen coined the term Dinosauria, derived from the Greek words ‘deinos’ & ‘sauros’, meaning “fearfully great,” and “lizard” respectively. Dinosaur fossils have been found on all seven continents.
All non-avian dinosaurs went extinct about 66 million years ago.
There are roughly 700 known species of extinct dinosaurs.
Modern birds are a kind of dinosaur because they share a common ancestor with non-avian dinosaurs.
The Age of Dinosaurs
The earliest known dinosaur appeared about 245 million years ago during the Late Triassic Period (250 to 210 million years ago). Dinosaurs evolved into a very diverse group of animals with a vast array of physical features, including modern birds.
Contrary to what many people think, not all dinosaurs lived during the same geological period. Stegosaurus, for example, lived during the Late Jurassic Period, about 150 million years ago. Tyrannosaurus rex lived during the Late Cretaceous Period, about 72 million years ago. Stegosaurus was extinct for 66 million years before Tyrannosaurus walked on Earth.
During the Mesozoic Era (a period of more than 180 million years that included the Triassic, Jurassic, and Cretaceous periods), a species of non-avian dinosaur evolved into a species of avian dinosaur. This avian dinosaur is the first bird and the forerunner of all birds. Every non-avian dinosaur went extinct 66 million years ago.
There are several theories as to what may have contributed to the mass extinction of non-avian dinosaurs and other species at the end of the Cretaceous Period. It is certain that a massive asteroid or comet struck Earth during this time, causing a dramatic shift in Earth’s climate. Some scientists speculate that this impact had catastrophic consequences for life on Earth. But other factors, including changing sea levels and large-scale volcanic activity, may also have played a significant role in this mass extinction.
Teeth, Footprints, and Feathers
Most theropod dinosaurs, such as Tyrannosaurus, had teeth that were pointed, slightly curved backwards, and serrated. The sharp points pierced the meat, and the serrations helped slice it by catching and tearing muscle fibers. Meat eaters didn’t chop or grind their food; they swallowed chunks whole.
Plant-eating dinosaurs had teeth of various shapes designed for their particular diets. Triceratops, for example, had hundreds of teeth that formed a solid “wall” with sharp ridges. The teeth were used to chop off vegetation. Other plant eaters, such as Anatotitan, had wide flat teeth that they used to grind up tough vegetation. The long-necked dinosaurs, such as Diplodocus, had long pencil-like teeth that they used to rake the leaves off branches. These dinosaurs swallowed the leaves whole. They also ingested small stones, called gastroliths, most likely to grind up the food in their stomachs, much the same way modern birds, such as parakeets and chickens do today. From an individual footprint, scientists can estimate the height of the dinosaur that made it. A rough estimate of leg length is obtained by multiplying the print length by four.
A footprint can also provide clues about the kind of dinosaur that made it. A three-toed, sharp-clawed print means the footprint-maker was likely a theropod—usually a carnivore. A three-toed print with rounded toes probably belonged to an ornithopod dinosaur—an herbivore. And pairs of unequal-sized prints were most likely the work of the four-legged, long-necked, long-tailed dinosaurs called sauropods, another group of herbivores.
Modern birds, or avian dinosaurs, have skeletal features that are almost identical to some non-avian dinosaurs. Feathers evolved before flight and may have functioned as insulation to keep dinosaurs warm, or for display as a way to attract mates.
Compiled by Bello Sodeeq Adekunle