GENERAL JURASSIC DINOSAUR FACTS
Which major Jurassic period dinosaurs were herbivores and carnivores?
The largest dinosaurs in the Jurassic tended to be plant eaters. The best known examples include the long-necked sauropods like Brachiosaurus and Apatososaurus, creatures that ate leaves off the tops of high trees. In addition, all of the ornithischians were herbivores, such as the plated Stegosaurus and the ankylosaurs. Ornithopods such as Camptosaurus competed with the large sauropods for vegetation. In contrast, the theropods were all carnivores, and evolved into large predators, such as the Megalosaurus and the well-known Allosaurus.
What were some of the smallest and largest dinosaurs known in the Jurassic period?
Some of the dinosaurs living during the Jurassic period evolved into the largest creatures ever to live on land with the majority being plant eaters. And it seems as if every year brings a new fossil discovery that unearths another, larger dinosaur.
The largest complete dinosaur so far discovered is the Brachiosaurus, which measured 75 feet (23 meters) in length and 46 feet (14 meters) in height, or about the height of a four-story building. But this Jurassic dinosaur has yet to win the ultimate big prize. The reason for this hesitation in giving the Brachiosaurus the largest status is familiar in dinosaur studies: there are too few skeletal remains of larger dinosaur species, with only fragmentary leg bones and vertebrae. This makes determining the size of these dinosaur species difficult. For example, many fragments point to such possible larger dinosaurs as the Argentinasaurus and Amphicoelias, both of which may have been one and a half to two times larger than Brachiosaurus.
The two longest dinosaurs in the Jurassic period may have been the plant eaters, the sauropods Diplodocus and Supersaurus. The Diplodocus measured more than 90 feet (27 meters) in length; the Supersaurus, thought to be a major contender as the longest land animal ever on Earth, measured close to 138 feet (42 meters) long and 54 feet (16.5 meters) tall. At one time, scientists believed that these huge creatures had to live in the water to support their great bulk; but the latest research suggests that the dinosaurs were able to carry their weight on land.
The smallest Jurassic dinosaurs, called the Compsognathus (pretty jaw), were just slightly larger than a chicken. This dinosaur was 3 feet (1 meter) long and probably weighed about 6.5 pounds (2.9 kilograms).
Larger carnivorous dinosaurs included the Allosaurus, which measured about 50 feet (15 meters) in length. Scientists believe the attack of the Allosaurus was amazing: it would open its mouth to the furthest extent, running headlong into its victim. Its 60 curved, dagger-like teeth would plunge into its prey, driven by two tons of dinosaur.
Did the first dinosaur fossil to be named come from the Jurassic period?
Yes, the first dinosaur fossil to be named was the Megalosaurus, named by geologist William Buckland (1784-1856) in 1824. The fossil came from the Middle Jurassic, and was found in Oxfordshire, England.
What possible large Jurassic dinosaur is only known from drawings of a fossil?
The Amphicoelias (doubly hollow) was a herbivorous sauropod dinosaur that included what may be the largest dinosaur ever discovered A. fragillimus from the Late Jurassic period. The evidence a single fossil bone was uncovered in the 1870s. If the description is true, it may have been the longest known dinosaur vertebrae, measuring 131 to 196 feet (40 to 60 meters) in length, with the animal weighing in at 135 tons (122 metric tons); thus rivaling the blue whale, the heaviest animal ever known. However, because the only fossil remains were lost at some point after being studied, the evidence survives only in drawings and field notes.
What Jurassic period dinosaur was formerly called Brontosaurus?
The Apatosaurus was formerly known as the Brontosaurus. Fossils from the Apatosaurus were officially named in 1877, while the Brontosaurus fossils were named in 1878. It wasnt until later that it was noticed that the fossils of the two dinosaurs were really the same. Since the Apatosaurus had been named first, it was adopted as the official designation for this animal.
Once commonly referred to as the Brontosaurus, this long-necked sauropod is now more correctly referred to as the Apatosaurus (iStock).
What Jurassic period dinosaurs lived the longest?
The herbivorous ornithopods lived the longest, from the Early Jurassic to the Late Cretaceous period. They include a series of successively larger and more massive dinosaurs that spread throughout most of the continents. One was the Heterodontosaurus of the Early Jurassic period, a quick, 4-foot (1.3-meter) dinosaur, with strong front canine tusks and flexible hands used for digging and gasping vegetation.