How many dinosaurs are there

Pterosaurs were not dinosaur. Elasmosaurus was the longest plesiosaur at up to 14 metres 46 ft long. Half of its length was its neck, which had as many as 75 vertebrae in it in comparison to neck vertebrae in humans. Elasmosaurus had four long, paddle-like flippers, a tiny head, sharp teeth in strong jaws, and a pointed tail. Plesiosaurs were not dinosaurs but were marine reptiles. It is believed that dinosaur extinction was part of a mass extinction brought about by two massive destructive events.

The first of these was the collision with the Earth of a meteorite landing in what is now the Yucatan Peninsula, of Mexico. This was followed by an enormous volcanic eruption which split what is now India in half. At present over different species of dinosaurs have been identified and named.

However palaeontologists believe that there are many more new and different dinosaur species still to be discovered.

So far species of dinosaurs have been discovered in Britain. Britain was an important area during much of the Mesozoic Era acting as a 'land bridge' between North America and Eurasia. It became a hotspot for dinosaur evolution and migration.

The dinosaur Museum has the skeleton of a Megalosaurus and the skull of an Iguanodon on display. The oldest known dinosaur so far discovered in Britain is Thecodontosaurus antiquus. It was discovered near Bristol in but only now has funding been achieved to excavate the dinosaur.

Thecondontosaurus was 2. It lived on the richly vegetated islands that were around that area in Triassic times about million years ago. The first discovery of dinosaur remains in North America was made in by Ferdinand Vandiveer Hayden during his exploration of the upper Missouri River. Only two are considered valid today.

Cope named a handful of genera himself, all quite fragmentary, that most likely belong to Triceratops. If you look at dinosaur genera, on the other hand, you might notice that most contain only one or two species.

The lizard genus Varanus alone contains over 50 living species with a wide diversity of sizes and shapes. Entomology blows this out of the water, with some insect genera containing over species each. This has led some authors to suggest that dinosaurs are over-split, and that many similar genera should really be lumped together.

This has especially pertained to genera that tend to have different-looking skulls but are pretty darn similar from the neck down. With their variation in size and shape, it seems like dinosaur species put a lot of value in standing out from one another. Other fields of biology tend to focus on the overall similarities, though. Entomologists would likely balk at the idea of the ceratopsids, for example, being over 40 distinct genera with only one or two species in most of them.

Clockwise from the top left: Lambeosaurus lambei , Hypacrosaurus altispinus , Corythosaurus casuarius , and Lambeosaurus magnicristatus. Are they actually all the same genus? Does it matter? Author and artist Gregory S.

Paul has historically gone to controversial lengths with dinosaur lumping. Arguing that many related dinosaur genera were indistinguishable beyond their skulls, Paul has attempted to synonymize many dinosaur genera over the years. Paul has also argued, for example, that the lambeosaurines Corythosaurus , Lambeosaurus , and Velafrons should be lumped in with Hypacrosaurus , and that a good chunk of centrosaurines should be lumped under Centrosaurus Paul, Darren Naish says more about this here.

If these examples and the many others that Paul has as asserted were widely accepted by paleontologists, the number of valid dinosaur genera would be remarkably low. However, such a wide taxonomic reworking would require an enormous amount of research and data to be scientifically supported.

Naming and categorizing dinosaurs is a useful way of scientifically studying and understanding them. As humans, we love to sort, classify, and count things. Does it really matter, though, if for example Eotriceratops xerinsularis turned out to be just an early species of the genus Triceratops? Does anything really change? Not really. Paleontologists and other dinosaur nerds like me love to debate the minutiae of things like names and classifications, but these are all human creations to describe living things at one particular point along an evolutionary spectrum.

So, the number of dinosaur types is not a definite, ascending number. Rather, it partly depends on who you talk to and what evidence you value. Regardless of all the debate though, paleontologists continue to discover new ones, and that will always be exciting. Birds are descended from one group of dinosaurs called the predatory theropods.

Theropods have hollow bones and three-toed limbs. Dinosaurs from the Tyrannosaurus are a type of predatory theropods. Read more: Curious Kids: will the universe expand forever, or contract in a big crunch? Megalosaurus was one of the first dinosaurs to be properly studied. It lived in the Jurassic Period, about million years ago. Today, we know they are not lizards, but a totally different kind of reptile. Each year scientists dig up more new dinosaurs and get to name them.

About 50 new dinosaurs are named every year. Volcanologists want to put sensors directly into an Underground Magma Chamber Sep 16, Related Stories. Just how good or bad is the fossil record of dinosaurs? Aug 28, Aug 07, Mar 16, Newly discovered dinosaur reveals how T. Jun 03, Sep 14, Recommended for you. Interdisciplinary research shows the spread of Transeurasian languages was due to agriculture Nov 10, Nov 09, Slave room discovered at Pompeii in 'rare' find Nov 06, Nov 03, Oct 29, Load comments 1.

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