Brontosaurus
Brontosaurus, meaning "thunder lizard" in Greek, was a large, gentle herbivorous dinosaur that roamed during the late Jurassic period. This massive creature could reach lengths of up to 72 feet (22 meters) and weigh as much as 19 tons. Characterized by its long, slender neck and tail, Brontosaurus had a relatively small head, which housed a small brain; some theories even suggest it possessed a second brain located near its hips to assist with tail movement. As a member of the sauropod family, Brontosaurus primarily fed on tall plants and treetops, utilizing special air pockets in its neck to support its size and reach.
Brontosaurus traveled in herds for protection against predators, with stronger individuals defending the group using their powerful tails and sharp claws. While it had limited means of defense against fierce carnivores like Allosaurus, its social behavior provided some safety for younger and weaker members. Nesting sites of Brontosaurus have revealed average clutch sizes of five eggs, suggesting the species laid multiple batches annually. Fossils have been discovered primarily in the Western United States, indicating that Brontosaurus thrived in warm, rain-soaked environments, although earlier beliefs about its swamp habitation are now considered unlikely due to its substantial weight.
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Brontosaurus
Brontosaurus, or "thunder lizard" in Greek, was a large, gentle, four-legged plant-eater that lived during the late Jurassic period. It had a long, slender neck and tail and a small head. Its huge body could weigh tens of tons. Some believe Brontosaurus had two brains, one in its head and one in its hip.
Kingdom: Animalia
Phylum: Prehistoric
Class: Dinosauria
Order: Saurischia
Family: Diplodocidae
Genus: Brontosaurus
Species: Brontosaurus excelsus
The name Brontosaurus excelsus experienced controversy in the 1900s and early 2000s. For some time, archaeologists believed the fossils were the bones of another extinct Diplodocidae, called the Apatosaurus. A 2015 study confirmed the classification of the uncovered bones was accurate.
Brontosaurus belonged to a group called sauropods that were large, four-legged plant eaters. An adult brontosaurus could be as long as 72 feet (22 meters) and weigh up to 19 tons. Its long, slender neck was more than 20 feet long, and its heavy, 30-foot (9-meter) tail dragged behind it as it walked. The head of Brontosaurus was tiny in comparison to its large body. It had a small brain and was not thought to be a very intelligent animal. Some scientists think Brontosaurus had two brains, one in its head and the other near its hip. The hip brain helped the Brontosaurus move its long tail more easily because the thoughts from the brain did not have to travel all the way from the head. The nostrils of Brontosaurus were not at the end of its long nose but at the top of its head behind its eyes. It was thought this helped the animal breathe when it walked through deep swamps. Brontosaurus was covered with a light brown, leathery skin.
Brontosaurus was a sauropod or plant eater. Its long neck allowed it to reach tall plants and treetops, where it ate leaves and vegetation that shorter dinosaurs could not reach. Special air pockets in their necks made them lighter and helped them reach food. Because it had a very weak jaw and small, dull teeth, it could not eat some tough plants, like conifers (plants with cones). Brontosaurus also ate stones to help them digest unchewed food.
Brontosaurus did not have the sharp spines or protective plates covering its skin like those on the Triceratops. It had to use other methods to protect itself. Because Brontosaurus traveled in herds, it could place the younger and weaker members in the center of the herd. When the herd was attacked by a predator, the stronger Brontosaurus would use their long, powerful tails as whips. Brontosaurus also had a sharp claw on the inside of each front foot used to lash out at the enemy. Many times, Brontosaurus was attacked by a group of meat-eating Allosaurusone of Brontosaurus' biggest and deadliest enemies. Fighting the Allosaurus, the long tail and sharp claws offered little protection.
The nests of Brontosaurus that have been discovered have contained an average of five eggs each. Scientists believe they laid several clutches (bunches of eggs) each year. The eggs were 12 inches in size with a rough surface like sandpaper. The mother Brontosaurus placed the eggs in shallow pits beneath the soil until they hatched. It is unknown how long the incubation period (how long an egg takes to hatch) was.
Brontosaurus lived in a climate with sunshine and warm rain, where plant life and vegetation grew. Scientists once thought Brontosaurus lived near or in the swamps. Modern scientists believe they would have gotten stuck in the mud because of their enormous weight.
Fossils of Brontosaurus have been found in Colorado, Utah, and parts of the Western United States.
Bibliography
Choi, Charles Q. "Why Was the Name ‘Brontosaurus’ Brought Back from the Dead?" Live Science, 31 Dec. 2023, www.livescience.com/animals/dinosaurs/why-was-the-name-brontosaurus-brought-back-from-the-dead. Accessed 17 Mar. 2024.
Osterloff, Emily. “Brontosaurus: Reinstating a Prehistoric Icon.” Natural History Museum, www.nhm.ac.uk/discover/brontosaurus-reinstating-a-prehistoric-icon.html. Accessed 17 Mar. 2024.
Wood, Katie. "Brontosaurus." A-Z Animals, 13 July 2023, a-z-animals.com/animals/brontosaurus. Accessed 17 Mar. 2024.