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Theropod Definition

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Theraoda whose members are known as theropods is a clan of dinosaurs who have hollow bones and three-toed limbs. They are generally classified into a group of forest dinosaurs. According to the ancestral chain, they are primary carnivorous; although a number of theropods are also believed to be Omni words, Harvey was PC boards and insectivorous. The theropods first appeared at the end of the Triassic period: the Carnage age, which was 230 1.4 million years ago. They included the giant terrestrial beings present from the Jurassic until the close of the cretaceous period. In the Jurassic birds, birds evolved from the coelurosaurian theropods and are represented by more than 10500 living species today. From the above theropod definition can be clearly understood. 

  • Kingdom- Animalia

  • Phylum- Chordata

  • Class- Reptilia

  • Order- Saurischia

  • Clade- Dinosauria

Morphology of Theropods

Teeth and Diet

A wide range of diets was seen in the class of theropods, starting from herbivores and carnivores. But adamantly carnivory has always been considered the preferred diet of theropod dinosaurs as a clan, and diversifying variety of diets was regarded as a treat which was exclusive to the avian theropods, however, according to the recent studies and discoveries, the variety of diets were in existence in even more basal or foundational lineage. Earlier evidence shows that the theropod fossils are mainly carnivores. The fossilized samples of early theropods found by scientists in the 19th and 20th centuries all had the distinguishing feature of teeth with crude and serrated edges for cutting into flesh, a typical characteristic present in the anatomy of carnivores. This was the primary evidence of the Predatory nature of theropods.

The first evidence of a non-carnivorous theropod fossil was therizinosaurs, which were initially known as segnosaurs. Many herbivorous theropods were later proven to be highly specialized, thought initially to be prosauropods. This possessed very large abdomens, which were fundamentally designed to process plant food, and they had sharp teeth and small heads with beaks. The later study of many rap torrent theropods and their relationships show that the therizinosaurs were not the only early member who abandoned carnivory. Several other lineages also show adaptations of the Omni diet, which included seed-eating and insect-eating. The type of diet is primarily influenced by the morphology of the tooth, gut contents, and the tooth marks on the bones of the prey. Some theropods such as Baryonyx, theropods species, and many bird species are using gizzard stones to do this.

While most of the species had head teeth that were blade-like and had crooked edges with serration called ziphodont, some of them were pachytene or phyllodont, depending upon the size of denticles. One can tell apart the family on the sole basis of the morphology of teeth only.

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Morphology of the Forelimbs

Shortening forelimbs with the hindlegs is a common trait among theropods. Although this strait was not universal, spinosaurus had world-developed full names and the relative robustness of the forelimbs of one gene. The hands were also quite different among the different groups. When the most common form among theropods was an appendage consisting of primary three fingers, the digits 1 2 and 3 e with sharp claws some basil theropods head four digits two and also had a reduced metacarpal usually had four digits file most tetaburans had three.

While it is also believed that the use of forelimbs was very different in different families, the dinosaurs could have had powerful four limbs to hold onto their prey. Some of them use them to climb trees even. While in the case of the modern birds, these are used primarily for flight, all know there adapted for different processes and different groups. For example, aquatic birds such as penguins use their wings as flippers.

Forelimb Movement of Theropod

Theropods were reconstructed in the popular media, the range of motion of theropods was severely limited, especially if they are compared to the locomotion and falling dexterity of humans and other terrestrial primates. Most notably, the theropod dinosaurs could not possibly use their hands; and could not rotate it so that the palms face the ground or backward towards the leg. While in homo sapiens sapiens, the pronation is achieved circular movement of the radius with Ulna, the two bones of the forearms. In saurischian dinosaurs, however, the end of the radius was nearer to the elbow, locked into a cluster of Ulna, preventing any movement. The wrist movement was also severely limited in many species, which forced the entire forum and hand to move as a singular unit contrary to two separate companies. In theropods, the only way that the palms faced the ground would have been by the lateral playing of the entire full life as while as in a bird raising its wing.

Feathers Scales and Skin

The Mesozoic theropods had very diverse characteristics when it came to skin texture covering, and colour. The feather-like structures or others were seen to be attested two most of the class of theropods; however, in some of the cases, the feathers may have been seen only in the young and smallest species or somewhat limited parts of the animal. In addition, while the majority of the more giant theropods had small and bumpy scales all over their body and skin in some species, these were replaced by enormous scales having bony cores.

The ceratosaur featured this type of skin which was preserved with very extensive skin indulgence. The ones who were the most distance from bird's head feathers that were comparatively shorter and composed of very simple branching filaments were the coelurosaurs clan or lineages.

In the theropods, they possessed will-like feathers, extensive and usually written skills only on their feet. Some species may have possessed mixed feathers in other parts or as a whole body. For example, Juravenator may have been scaly as compared to other species of theropods. Contrary to that, Some were completely covered with feathers, such as the troodontid, covered in feathers from head to feet.

Size of Theropods

The largest known theropod was the Tyrannosaurus rex and best known to the general public. However, several other giant dinosaurs since the discovery of theropods have been described, including spinosaurus, Giganotosaurus, etc.

The newer fossils described in 2016 depict that spinosaurus may be 3 meters longer than the tyrannosaurus, although tyrannosaurus could still be massive than spinosaurus. The heaviest theropods that have been discovered till now are sue and Scotty. Till now, there is no clear explanation for exactly how these animals grew so heavy and bulky compared to other terrestrial predators that came before and after them.

The common ostrich is the largest extent theropod is known to mankind, which is about 2.74 meters or 9 feet tall, and it is between 90 and 130 kg. However, the smallest non-avian theropod known from the adult specimens is the troodontid Anchosrnia Huxley, which weighs around 100gms in weight and 34 cm in length. When modern birds are considered, then The bee hummingbird is the smallest, weighing 1.9 gm and 5.5 cm long.

The recent theory proposes that the theropod body shrank continuously over 50 million years from an average of around 163 kilograms in the Cretaceous period to 0.8 kilograms. Eventually, evolving into the modern birds that we know today.  This is solely based on the evidence that the theropods were the only dinosaurs who got smaller and smaller with the advancement of time that their skeletons changed 4 x to the rate of change of skeletons of other dinosaur species?

Gait and the Stance

As this is a group of hugely and significantly diverse animals, the poster adapted by the theropods varied considerably between various lineages throughout the time. All the known theropods known to humankind are named bipedal, that is, the four limbs reduced to a length ENT specialist for a wide variety of tasks. On the contrary, the modern birds, the body d is typically held in a somewhat proper manner or position. The upper leg is the famous hell parallel to the spine, and the knee generates the forward movement of the whole body. Even the most brilliant scientist is unsure how far back in the theropod family this type of poster or movement existed.

Known evian theropods were first recognized as bipeds at the end of the 19th century. Just before they wore the birds' ancestors, there was a massive controversy that they might not be related to the existing theropod organisms. With vertical feet and spines in a very operational manner which was nearly, and erect posture this happened by using their long muscular tails as an external support which can be found today in kangaroos which can like in tripods. The biomechanical studies in 1970 significantly studied the extinction of giant theropods, which cast doubt in this observation. The detailed study of the limb bone articulation and the relay after their analysis was evident for tail dragging. This suggested that when they walked, the giant long-tailed theropods had a horizontal stand or poster with the tail held parallel to the ground.

This orientation, however, remains controversial. Some of the theories support that traditionally oriented long-tail theropods could walk despite their giant body. It is highly likely that the wide range of body postures and stands were very diversely satisfied and may have been found in many extinct theropod groups whose fossils are yet to be discovered.

Anatomy of Theropods

Although the proper nervous system and the various sensors of theropods are complicated to find, the complete cast of theropod endocranium, known as fossils, is being reconstructed from preserved braincases that are not damaged. One can quickly e cost an endocranium by using 3D construction software and by using computed tomography. These findings are of very high significance in the evolutionary prospect because they give a detailed document of the neurology of modern birds from their earlier ancestors. The increase in the proportion of brain occupied by the cerebrum may have occurred with the advent of Coelurosaurs and has been continuing throughout the evolution of maniraptorans and early birds.

Research on Theropod

Ralph E. Molnar, in 2001, Published a survey about theropod dinosaur bone. He found out that the pathological features in the 21 general from the ten families somewhat familiar. The theropods of all body sizes were significantly less common fossils of small theropods found to be an artifact of preservation. These artifacts are widely represented throughout the history of value paleopathology in different parts of theropod anatomy.

The most common places of preserved injury and disease in theropod dinosaurs were the ribs and tails, despite being very abundant in the ribs and vertebrae. These injuries were rare or absent on the body's primary foundation or supporting bones like the sacrum, femur, and Tibia. This lack of preserved injuries suggests that they were evolved for the resistance of breakage. The least common sites of injuries were the cranium and the forelimbs. Most pathological kept in history are fractures, pits, and punctures which are generally cuadedare by bites. Search discovery scans provide information regarding the process of biological development. Diffusions of cranial elements in the same is probably the evidence that the fossils are extremely old individuals rather than diseased ones.

FAQ (Frequently Asked Questions)

Que1: Can Theropods Swim?

Ans: Yes, the theropods can swim. This evidence was first discovered in the Sichuan province of China. The evidence supports that dinosaurs' swim tracks were scarce fossils that were found in China. Furthermore, it indicated that a different class among the very classes of vertebrates could swim, including pterosaurs and crocodylomorphs.

Que2: What is the difference between Theropods and Other Dinosaurs?

Ans: While other dinosaurs were Herbivores such as the triceratops that theropods such as Tyrannosaurus Rex were primarily carnivores. That can be seen by the blade-like teeth and sharp edges of them in Theropods which is not seen in the herbivore dinosaurs.

Que3:  Could Theropods Fly?

Ans: Yes, most probably as the evidence and Fossil suggest, many species of the theropods could have the ability of flight as indicated by the wing-like shaped forelimbs. These flying species of theropods very close connection to the birds of our present era. These flying species are significant as they are the connecting link between the Avian species and the reptiles.