Liang Long

Liang Long

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Diplodocus (scientific name: Diplodocus) is a dinosaur belonging to the family Diplodocus. Its skeleton was first discovered by Samuel Wendell Williston. Liang long lived in western North America at the end of Jurassic, dating back 150 million to 147 million years ago. Individuals can be up to 30 meters long and weigh about 10 tons. The nostrils are above the eyes. Their necks couldn't be raised, presumably to enlarge the area of feeding in situ.

morphological character

Lianglong is one of the most easily identified dinosaurs, with a huge body, long neck and tail, and strong limbs. Many years ago, it was considered the longest dinosaur. It is large enough to deter (possibly contemporaneous) predators such as Allosaurus and hornnose found in the same strata.

Lianglong is longer than puzzling dragon and Brachiosaurus, but it has a long head and tail, a short trunk and a thin body, so it is not heavy. Although Lianglong has a long neck, its neck can not bend freely like plesiosaur because of the small number and toughness of neck bones. The nostrils of Brachiosaurus, leilong and Lianglong were all on the top of their heads.

Liang Long is 27 meters long. Because of its light back bone, it is thin and small, weighing only a dozen tons. Its weight is far less than that of puzzling dragon and brachiosaurus. Its teeth only grow in the front of the mouth, and very small, so it can only eat some soft and juicy plants. The long whip like tail can help it resist enemies and drive away other small animals wherever it goes. It can be imagined that when Liang Long was eating, his tail was constantly whipping. Lianglong is a huge dinosaur. Its neck is 7.5 meters long, its tail is 13 meters long, and the longest is 14 meters. Despite its large size, Liang's head was small and slender. It has nostrils on its head. The front of the mouth has flat teeth, while the sides and back of the mouth have no teeth. Its front legs are shorter than its back legs, and each foot has five toes, one of which has claws. Liang Long's head is very small, so it's not smart. Lianglong is a herbivore. When eating, it does not chew, but directly swallow leaves and other food. Some large carnivorous dinosaurs would prey on Lianglong. If 20 9-year-old children were allowed to lie on the ground head to foot, the length of their composition was almost the same as that of Lianglong. Liang Long's neck is thin and long, his tail is like a whip, and his four legs are like pillars. Liang's hind legs are slightly longer than his forelegs, so his hips are higher than his front shoulders. From its slender, small head to the tip of its huge tail, Liang's body is supported by a series of interconnected axial bones, which we call vertebrae. Its neck is composed of 15 vertebrae, chest and back have 10, and slender tail has about 70! Although Liang Long's body is huge, it can support itself from the ground with the strength of its neck and tail. Liang can whip the enemy with its powerful tail to force the attacker to retreat, or stand on its hind legs and support part of its weight with its tail so that it can defend itself with its huge forelimbs. There is a huge and curved claw on the toe inside the forelimb of Lianglong, which is its sharp self-defense weapon. Like the heel of a human shoe, Liang Long probably has a sole pad that can cushion his toes. With it, Liang won't feel too hard to support his heavy body when walking.

Discovery and species

Diplodocus hallorum, formerly an earthquake dragon

Several species of Lianglong were described and named from 1878 to 1924. In 1878, Samuel Wendell Williston discovered the first fossil of D. longus on Como cliff, Wyoming. In the same year, he was named D. longus by paleontologist othel chalis marsh. Later, Lianglong fossils were found in the Morrison formation of Colorado, Utah, Montana and Wyoming. Lianglong fossils are very common. Although relatively complete bones have been found, few skulls have been found. Although D. carnegiei is not a model species, the closest complete skeleton has been found, and its skeleton model has been exhibited in many museums around the world, and is the most well-known.

Lianglong and Chonglong, also found in the Morrison group, have very similar limb bones. In the past, some individual limb bones were included in the genus Lianglong, but in fact they may belong to Chonglong. All the stegosaurus fossils found in the Morrison formation are found in the fifth stratigraphic zone.

Effective species

Changlianglong

D. longus: type species, consisting of two skulls and a set of tails, found in the Morrison formation of Colorado and Utah.

Diplodocus carnegiei

(D. carnegiei): described and named by John Bell Hatcher in 1901, the species is named in memory of Andrew Carnegie. It is the most well-known because it is a nearly complete skeleton.

D.hayi

: a partial skeleton found near Sheridan, Wyoming, in 1902 was described and named in 1924.

D.hallorum

The fossil contains vertebrae, pelvis and ribs. It was first named by David Gillette in 1991, when it was the model species of Seismosaurus Halli. Because of the original grammatical error, George olshevsky later changed it to S. hallorum, and the new species name was quoted by Kenneth carpenter and others. At the 2004 annual meeting of the American Geological Association, earthquake dragon was changed to the synonym of Liang long. More in-depth research in 2006 not only renamed it D. hallorum, but also speculated that it was actually changlianglong. Another re study on the super dragon also thinks that D. hallorum is a specimen of the long Liang dragon, and refutes the idea that the earthquake dragon and the super dragon are the same animals.

Doubtful name

D. lacustris

(D. lacustris): it was named in 1884 by marsh based on smaller fossils found in Colorado and is now considered to be a suspect. The fossil is thought to have come from an immature individual rather than another species

Double beam

Lianglong's body is supported by a series of interconnected axial bones, called vertebrae. Its neck consists of 15 cervical vertebrae, 10 dorsal vertebrae in its chest and back, and about 70 caudal vertebrae in its slender tail. There are two herringbone extension structures in each segment of the caudal vertebra of Lianglong, from which the scientific name "Shuangliang" comes. This "double beam" structure can protect the blood vessels of the tail when the tail of the Dragon touches the ground and props up the body.

classification

Lianglong is the type genus of lianglongidae, and the name of lianglongidae comes from Lianglong. Although they are large, they are longer than other sauropods, such as titanosaurs and brachiosaurs. All of them are characterized by long neck and tail, horizontal posture, and short forelimbs. Lianglongke flourished in North America and possibly Africa in the late Jurassic, and its niche seems to have been replaced by the Cretaceous titanosaurs.

The subfamily lianglonginae includes Lianglong and its close relatives, such as Chonglong. At the same time, the distant relatives of melastosaurus were considered to belong to melastosauridae rather than melastosauridae. Some scholars believe that dinghelolon of Portugal and townylon of Africa are close relatives of Lianglong.

Leonosauridae includes leonosauridae, cladoceraceae, rabazisconidae, chunleilong and diplodosaurus, and possibly jianjilong and namogaturonae. Leonosauridae is a sister taxon of macronasosaurs. Macronasosaurs include domacrosauridae, carposauridae, and titanosaurs. These two evolutionary clades formed a new sauropod, which is the most diverse and successful sauropod dinosaur.

Habitat area

Marsh and hechel assumed that Lianglong lived in water based on the fact that Lianglong's nostrils were on the top of the skull. Other large sauropod dinosaurs, such as Brachiosaurus and fasciosaurus, are thought to have similar aquatic lifestyles. But in 1951, KennethA.Kermack It is proposed that the research object to this hypothesis, because when a sauropod is immersed in water, the chest pressure is too high, which makes it unable to breathe. Since the 1970s, sauropod dinosaurs have been considered to be land animals, feeding on plants.

Life posture

Since it was discovered, Liang Long's imaginary gait has undergone great changes. For example, in an early 1910 painting, the limbs of two Lianglong extended to both sides like lizards. But this hypothesis was overturned, because if Lianglong could spread its limbs, there must be a groove on the ground to place its abdomen.

Later, lianglongke is often depicted with its neck raised so that it can eat the leaves of tall trees. But scientists dispute whether their hearts can maintain enough blood pressure to supply blood to the brain. Furthermore, it was found that the neck structure could not be bent up excessively. In 2009, a study suggested that all tetrapods could hold their heads and necks high to alert their surroundings. The researchers also found that Liang's neck could be removed

Chinese PinYin : Liang Long