What is Coelurosauria ? What are the characteristics of Coelurosauria?

1. Coelurosauria is a Greek word which means (Coel-hollow, uro –tail, Sauria- Lizards) ie, Coelurus lizards or hollow tailed lizards. They have the largest Coelurosaurs including Tyrannosaurus and smallest one mainly Microraptor, Parvicursor etc. Coeurosaurs includes tyrannosaurs, ornithomimosaurs, and maniraptors.
i. Tyrannosaurs were having fused nasals. U-shaped pr-maxillary teeth, and slender metacarpals.
ii. Ornithomimosaurs were having a long neck, small skull, all same length matacarpals.
iii. Maniraptors have Large fore-limbs, large bony sternum, pubic pointing backward.
Coelurosaurs are the smallest types and feed on smaller prey.

2. Characteristics of Coelurosauria:
a. They were bipedal i.e. two feet (bi-two, Pedal-feet)
b. They were carnivorous.
c. Lower arm bone (ulna) was bowed.
d. Their lower leg bone(tibia) was longer than the upper leg bone (femur)
e. Their tail was stiffened towards the tip

Some other peculiar features of Coelurosaurs are:
(a). Enlarged brains: It is one of the main features of Coelurosaurs. They have a large brain that was at least double the size of those of other theropods having the same body size.
(b). They have long narrow, slender hand i.e. They have tridactyl (Tri-three, Dactyl-Digits) on the extremity of the manus (distal forelimb)
(c). They have Kayak-shaped (v-shaped) chevrons making the distal part of the tail particularly slender
(d). They have long narrow feet or metatarsals

3. As I already explained in reply to query no. 2, the Coelurosaurs possess slender grasping hands with tri-dactyl manus that means they have three fingers.

4. Yes, some Coelurosaurs are still live. Out of the three types of Coeurosaurs, Maniraptora, the smallest coelurosaurs, includes birds, the only progenies of coelurosaurs that are still alive. They first appear in the Middle Jurassic period and persist ever since. They have a resemblance to Dinosaurs. They belong to class Reptilia and suborder Dinosauria. Actually, Dinosaurs were the connecting link between reptiles and birds and was having a lizard-like tail but features like birds. Coelurosaurs are also feathered dinosaurs.

5. They have a global presence and present in almost all continents.

Coelurosauria evolved from Greek word which means hollow tailed lizards. It is a clad containing theropod dinosaurs related to birds than to carnosaurs. It is a subgroup of theropod dinosaurs which includes compsognathids, tyrannosaurs, ornithomimosaurs, and maniraptorans.Maniraptora is the only known dinosaur group which survive on earth.
The main characteristics of coelurosaurs is elongated arms and well- developed hinge-like ankles. It has relatively large brains and are characterized by slender grasping hands with three fingers. It is carnivorous in nature. Their appearance are like dinasaur. Dinosaurs belonged to reptiles class. They first appeared during the Triassic period, between 243 and 233.23 million years ago. But, exact timing of origin are yet unknown. Coelurosaurs looks like feathered dinosaurs. Some kind of Coelurosaurs are still survive on earth. It is found all over the world.

Taxonomic research about coelurosaur is constantly being done by paleontologists (A paleontologist studies the history and process of evolution by examining fossils, the preserved traces of extincted animals and plants) and new study discovers new information about these exitncted animals.

Coelurosauria can be understood as the clade (The clade is a group of biological taxa or species that share features inherited from a common ancestor) which all theropods (A theropod was a dinosaur clade that had hollow bones and three-toed limbs) were like birds. Some of coelurosaurs had elongated arms and well- developed hinge-like ankles also. These characteristics or features might be lost or modified by later coelurosaurs over the long ages. However, All the theropods were bipeds; they would walk on their hind legs wheras the short hands were used for grasping and tearing prey.
All coelurosaurs exhibit a great quantity of morphological resemblances with birds, but various coelurosaurs lack different bird-like facets also.
Birds are descended from one lineage of small theropods and therefore are members of Theropoda.

Major coelurosaurian groups:

Maniraptora: Velociraptor, birds, and other coelurosaurs
Ornithomimidae: The bird-mimic coelurosaurs
Tyrannosauridae: The giant coelurosaurs

If we go through the history of dinosaurs then we will find that they ruled the Earth for a long time which is amazingly large range of time (about 245 to 66 million years ago) and during that duration many changes happened to the continent disposition as seen on the surface of Earth. As per the scientific studies it is found that at that time the continents started to take their shapes from a common main mother continent known as Pangaea. This apparent split as seen on the surface of Earth punctuated with the oceans in between gave rise to different climates and other vegetation conditions through which the dinosaurs and many other species of the animals evolved. Dinosaurs survived mainly in hot climate and at that time Earth was having that type of conducive environment and even the polar ice caps were not formed. In fact the Earth was getting cooled gradually from its earlier high temperature.

Geologists have divided the above period in three distinct parts known as the Triassic, Jurassic and Cretaceous. During those periods many different types of dinosaurs evolved based on their geographical position on the continental masses and the respective climate at that point of time. The Coelurosauria group of dinosaurs evolved during the Jurassic/Cretaceous period and it is interesting to note that they were the feathered ones and from these species only the birds also got evolved during that period.

Another interesting thing to note is that during the end of the cretaceous period the dinosaurs practically got extinct and there are various theories propounded for their extinction. Please note that as the Coelurosauria group of dinosaurs were feathered one, some of their species could survived with the changing environment or disaster at that time which is supposed to be the cause of dinosaur extinction. So, in essence some of them survived and we see them today in their present get up after so many million years. It is also interesting to note that we the human beings started to evolve from our apelike ancestors only about 5-6 million years ago. On the other hand some of the species of Coelurosauria group of reptile creatures are still surviving since so long (since hundreds of million years).

The reptile like creatures of this group are known as coelurosaurs which means 'hollow-tailed reptiles' and are generally small to medium size unlike the mammoth dinosaurs of the past era. They have feathered features and some of their species were more akin to birds and are closely related to them. During the evolutionary phase, the coelurosaurs also developed in so many types in so many sizes and shapes, and the present one are one among them, which survived such a long duration of time. Coelurosaurs have finger like toes on their feet and there are four toes which remain touching the ground and also have backward pointing pubes. This is what they have in place of fingers. These reptile type creatures are found in many parts of the world. They are the true reminiscent of the mighty dinosaurs.