Dinosaurs

some did but not the meat eaters

Archaeopteryx is a Jurassic fossil bird that shares both bird and reptile features; it is widely accepted as the earliest and most primitive known bird. Fossils show the presence of wings and feathers, as in birds, but also teeth (which modern birds do not have), claws on the wings, and a long, lizard-like tail, with tail vertebrate, such as with reptiles (March 2001). The description of the first intact specimen in 1861 (two years after Charles Darwin published The Origin of Species), set off a firestorm of debate about evolution and the role of transitional fossils that endures to this day.

As far as the largest ones are concerned, their size implies need for great amounds of energy, which means they had to eat a lot. Ectothermic animals don't need enough food, because they produce their energy utilizing the heat of the sun. This way, however, the bigger an animal gets, the more time it takes to generate heat and this may cost its own life, because in the meanwhile other smaller predatory animals have become active and threatening. The largest dinosars had to be endothermic, in order to, at least, stay alive. Some smaller dinosaurs, like Leaellynasaura, have been discovered to have lived in low latitudes near the Antarctic circle, which means they had to be endothermic to stand the climatic conditions. Even more, some small theropods present skeletal characteristics, like V-shaped bone of the chest (Velociraptor), which connects them with birds. Their 3-digit forelimbs, 4-digit long and erect hindlimbs (built for speed) , the structure of metacarpal and their respiratory system are also signs which imply connection with birds and some theropods from China (Sinosauropteryx, Sinornithosaurus etc) even present signs of feathers or proto-feathers. Since feathers imply ability of thermoregulation and, thus, high metabolic rate, scientists believe that some dinosaurs, if not all, eventually became endothermic, even if they had evolved from ectothermic ancestors. The evolutionary connection between dinosaur and endothermic birds is also implied by the discovery that early birds had a snout filled with teeth, long bony tale and digits on front limbs (wings), as well as scaly theropod legs.

True sturgeon evolved early in the Cretaceous. They have barely changed since then, making them living fossils. Today, however, many are threatened by humans.

No, Humans and Dinosaurs are in different time periods.

The first Dinosaurs were small Therapods (fast carnivorous/meat- eating Dinosaurs). Until recently the oldest Dinosaur known was the Eoraptor. Unlike many other Therapods it had five digits (fingers). Through time Therapods gradually lost digits. But there was one thing about its hand- two of the fingers were stubby while the three others were perfect for grasping. Herresaurus was the second oldest Dinosaur known until recently. It also had five digits and two stubby ones. This hunter was no small Dinosaur- it was 10 ft long! Scientists think it ate Mammals and small Theraspids. Eoraptor probaly only ate Mammals and Insects. Eoraptor and Herrerasaurus are part of the earliest group of Dinosaurs- Herrerasaurs. It was not long until a new group of Therapods appeared. These were the Ceratosaurs. They had S- shaped necks and hollow bones. One of the first Ceratosaurs was Coelophysis. It was a small and agile hunter. It was named for its hollow bones and once a Coelophysis fossil was found in space! Now lets move on to the herbivores (plant- eaters). The herbivorous Dinosaurs evolved from Therapods. The earliest herbivorous Dinosaurs were the Prosaurapods which later gave rise to the Saurapods (huge long- necked Dinosaurs). The Prosaurapods were armed with a pair of thumb claws. It is possible that some Prosaurapods were omnivores (animals that eat both plants and meat) and used these thumb claws to take down their prey. Some Prosaurapods also had fangs like the Therapods (Prosaurapods were more closely related to the Therapods then other herbivorous Dinosaurs). One of these Prosaurapods was Riojasaurus. Riojasaurus was one of the largest Prosaurapods (it grew up to 30- 36 ft long). It also belonged to the group of the largest Prosaurapods to ever walk the Earth- the Melanorosaurids. Not all Prosaurapods were huge. Some were small like Anchisaurus which was only 3 meters tall on its hind legs. And some were medium sized like Plateosaurus. Plateosaurus was 27.5 meters long. Now we can move on to the smaller herbivorous Dinosaurs- Ornithschians. The Ornithschian group was divided into 3 groups- Marginocephalians (the horned and bone- headed Dinosaurs), Thyreophorans (the armoured and spiked/plated Dinosaurs), and finally, the Ornithopods. The Ornithopods were the first Ornithschians. They came in all shapes and sizes- some were small, some were huge, some were known as the Dinosaur gazelles, some were slow, and some were even partly covered in protofeathers (a feather- like substance that warmed up the bodies of Dinosaurs). Pisanosaurus was one of the first Dinosaurs. Only partial fossils of this small Dinosaur have been found in Argentina. Then we have Lesothosaurus which will be the only other Ornithopod I'll tell about in this answer. Lesothosaurus was first found in Lesotho, Africa. This small Dinosaur was only 3 ft long like Pisanosaurus and was a fast runner. These are some facts about the first Dinosaurs. Hope this helps!

Predator X, the creature with the largest set of jaws and largest in length, (Tyrannosaurus Rex is the most famous dinosaur) has been living during the times that Europe was underwater and another area with an amazing reputation in the future is also flooded, the Sahara. But now the answer: Predator X's real name is Liopleurodon.

Triceratops may have lived either solitary or in herds. Either way, they would probably ignore any other herbivores in the area. If attacked by a predator, they may have run or fought back.

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bracheasaurus. They can reach to about to 5 storys high! brachiasaurus (brak-ee-a sor us) are very common dinosaurs. they are not attractive to movement and arent vicous lie other speices. they are about 30 feet long from head to tail. they have very long necks

Birds

Maybe you should look in your Science Book.....

The Dinosaurs lived in mainly three era's Jurassic, Triassic and Cretausous. forgive me for spelling mistakes.. Thomas Gibbons elliott st john

The largest dinosaur name is Micropachycepahalosaurus. The shortest is Minmi.

if temperature drops quick enough, plants die. if plants die, the dinosaurs that eat plants die. if those dinosaurs die, then the carnivorous meat-eating dinosaurs die. then, all dinosaurs die.

A cockroach

oviraptor meaning "egg thief."

further research revealed that the nest was likely that of the oviraptor and it was protecting the nest.

In general. to eat eggs is called ovivorous

dinsour are dead but some people say that some are alive like lizzards crocdiles and some birds i think

sorry for my spelling mistakes

they died

Since there aren't any dinosaurs around today the answer can only be speculative, however based on animals like the ones around today yes, they were likely to have slept standing up.

There are many theories but nobody knows for sure. The most popular theory is the meteorite theory. There is also the new vegetation theory. These are only a couple but there are many many more.

endotherms

Saltosaurus Segnosaurus Seismosaurus Spinosaurus Stegosaurus Stokesosaurus Struthiomimus Stygimoloch Styracosaurus Suchomimus Supersaurus Syntarsus