Long before man appeared on this planet Earth, dinosaurs roamed for over 160 Million years. Before then there were other prehistoric monsters. They evolved over time with new dinosaurs evolving and old ones dying out. Eventually, all the dinosaurs became extinct. Dinosaurs appeared in one of three main periods of the Earths life. The periods are Triassic (251-199.6 Mya), Jurassic (199.6 - 145.5 mya) and Cretaceous (145.5 - 65.5 mya). Mya = Millions of Years Ago. Considering how long they were on this planet, they were very successful.
Before the dinosaurs, there were other creatures who lived for millions of years. The most well known of pre-dinosaurs is Dimetrodon, which is a Pelycosaurus. Dinosaurs existed on every continent on the planet including Antarctica. When the dinosaurs were around, all the continents were grouped into one mass continent called Pangaea. In hundreds of millions of years time, it is expected the worlds continents will be joined again. The new supercontinent is referred to as Amasia. Humanity is expected to have disappeared by them. However given humanitys intelligence, our life form could quite possibly out-survive the dinosaurs. We may however evolve into another form. A calendar year then will be much longer because the Earth is slowing down encircling the Sun. Every 600 years, an extra hour is added to a calendar year.
Dinosaurs would have existed on every continent of the world, back then it was one whole supercontinent. The Iguanadon is found all across the world. There have been dinosaurs discovered on the frozen continent of Antarctica. In the prehistoric days, the continent wouldn't be in the present location but in a more northern position. Some people believe humans and dinosaurs co-existed, they never did. Dinosaurs were wiped out long before humans appeared on this planet.
When life first began on the planet, it was simple single cellular lifeforms for over a billion years. It was only after the cells began to become more complex that life began to take shape. The first prehistoric life forms would have been sea creatures who eventually evolved and made it onto land. The first creatures would've been ammonites and other molluscs then fish then lung fish and then onto land. One of the earliest creatures on this planet was the Dimetrodon which people might assume was a dinosaur but as mentioned before, it is a Pelycosaurus. Pelycosauruses became extinct before the rise of the Dinosaurs in the Triassic period. Pelycosaurus are more closely related to mammals than they are dinosaurs. A catastrophic event caused the end of the Pelycosauruses and led to dinosaurs. Over time, dinosaurs came and went, eventually all dying out due to what is believed to be an asteroid strike.
Although the first realisation of dinosaurs was made in 1676, dinosaur bones were known of for centuries before. Dinosaurs bones were thought to belong to dragons that breathed fire across the land and ate humans and livestock. The Chinese ground up dragon bones and used them as herbal medicine, not realising exactly what they actually were. Stories of dragons sprang up across the world most predominately in Europe and China.
Bones were probably as far back as Roman times but no one took any interest in them. The Chinese were aware of these bones but had always referred to them as being the remains of dragons, not to be touched. It is alleged the chinese to have ground up the bones and used in herbal medicine as they weren't aware of what they were looking at at the time. The Chinese historian of the time, Chang Qu mislabelled a dinosaur as a dragon. Ref: Act For Libraries .
The Inca's of Peru had a dragon Amaru which was probably inspired by the discovery of a dinosaur bone but not knowing any better, referred to them as dragons.
1676, the first dinosaur was discovered by accident in a limestone quarry near Chipping Norton in Oxfordshire, England. The discovery was of a large dinosaur bone which was then sent for analysis by scientists at the University of Oxford. Prof. Robert Plot, a chemistry lecturer was tasked with investigating the bone. He identified it as being a leg bone and believed it to belong to giants that were mentioned in the bible. He detailed this find in a paper called the 'Natural History of Oxfordshire'. The bone in fact belonged to a Megalosaurus but dinosaurs had yet not been fully discovered. Over the next couple of years, more bones belonging to Megalosauruses were discovered.
In the early part of the nineteenth century, Harvard and Yale scholars were interested in a fossilized footprint that had been found at a Massachusetts farm but there was no link to dinosaurs yet. Other fossils were discovered and discounted, they were ignored and the people working where they had been found just carried on with what they were doing.
1822, on the south coast, the second dinosaur was discovered by Mary Ann Mantell, wife of Gideon Mantell, a doctor. There is controversy over who of the couple actually discovered the giant tooth. The tooth was said to resemble a Iguanas but larger so the name given to it was Iguanadon, Iguana-toothed creature. This was when the interest in dinosaurs really began across England, Europe and America. Iguanadons have been found all over the world.
1838, the first dinosaur bones in America were discovered in a small town called Haddonfield, Camden, New Jersey. The bones were put on display but it was not until a visitor arrived in 1858 that the complete skeleton was finally assembled. It was identified and named before transferred to the Philadelphia Academy of Natural Sciences.
1842, they became known as Dinosaurs after the name was coined by Ref: Sir Richard Owen . The term is derived from derives from Greek deinos "terrible, powerful, wondrous" sauros "lizard". Richard Owen managed to persuade the Royal Family to back him as he set up the London Natural History Museum. This was where the dinosaur finds would be exhibited to the public.
In the early days of television and film, you would see humans and dinosaurs fighting for survival. Tyrannosaurs are usually seen fighting with Triceratops in earlier films. Those fights probably did happen in real life unlike against humans. That never happened in real life, the dinosaurs died out long before humans arrived on this planet. Sir Authur Conan Doyle, author of Sherlock Holmes stories wrote a story, "The Lost World" about where dinosaurs survived their extinction and live and breathe today. The central character Professor Challenger takes a group of people to Venezuala to explore the plateau. Although more associated with dinosaurs, a larger portion of the story is dealing with prehistoric humanoids.
Michael Crichton wrote about bringing dinosaurs back to life after Dinosaur DNA was found in a fossilised fly. The book, Jurassic Park was made into a film which became one of the most successful films of all time. Lesser known is a toy/cartoon series about people time-travelling back to the age of the dinosaurs to discover that the dinosaurs were enslaved and killed off by an alien race. In World of Warcraft, the zone 'Un'Goro Crater', dinosaurs roam unimpeded across the zone. In other zones, e.g.Arathi Highlands/Wetlands, (Veloci)Raptors roam with other creatures.
People claim that there is a sea monster living in the Loch Ness in Scotland however despite numerous investigation, nothing has been discovered as yet. The Loch is many feet deep and anything could hide down there. Some say it is a dinosaur whose ancestors survived all the great extinctions. There are people who claim to have seen it, there's photographic of a poor quality of the monster there. Until we see more proof there is something down there, it'll just be the stuff of legends and tourism.
Over millions of years, dinosaurs died off or were made extinct by an event. Triassic dinosaurs died off before the Jurassic dinosaurs appeared. If they were any Triassic dinosaurs around, they were on their death throes. At the end of the Cretaceous Period, a large percentage of dinosaurs were wiped off the face of the Earth. Dinosaurs no longer ruled or were never seen again on the planet.
The most widely accepted reason for the extinction of the dinosaurs is a meteorite crashing into the land/sea just off the east coast of Mexico causing the death of the dinosaurs. When the meteor hit, dust and particles were thrown into the air by the force of the collision. The dust blocked out the Sun causing vegetation to die off, followed by herbivores then carnivores. It wasn't a sudden event but one that took years to happen. However a few life forms survived the mass extinction, one for example is the crocodile. It took many years for the eco-system to get back to normal again and for new life to flourish. Humans weren't the first on the scene yet, other creatures made an appearance first. Mass Extinctions
You've probably seen films in the past such as "1,000,000 Years B.C.", which if you'd forgotten had Raquel Welch running around in the leather bikini, where dinosaurs and humans co-existed. They didn't, dinosaurs as has been said became extinct 65 Million Years ago, the general consensus amongst scientists is that humans first appeared about 1 - 2 Million Years ago in Africa.
Despite what some people might say, humans and dinosaurs never walked on the planet together. Those that say that humans and dinosaurs were on the Earth call the carbon dating as flawed and try to find evidence in scriptures of the past.
People fantasise as to whether Dinosaurs could one day walk the Earth again. Sadly that could not happen even with our scientific knowledge. To recreate a dinosaur, we would need to obtain DNA from fossilised remains. All attempts at doing so have met with poor quality DNA. Dinosaurs might not be coming back but Sabre-tooth Tigers and Woolly Mammoths could make a return. Taking DNA from those extinct creatures and impregnating a close relative of those creatures could create a hybrid. If you keep the taking the hybrid and getting it to mate with another hybrid by selection, you could create a near perfect extinct creature. Hybrids would have to screened so that they pass on as much extinct monster DNA as possible. The only probable way in which dinosaurs were to return is if we managed to create a time-machine to bring one back. Or alternatively, we manage to get off this planet and find a world where dinosaurs exist.