Re: Who gets to decide what to name a dinosaur? How many have been found?

Dinosaurs are named in exactly the same way as other animal and plant species, whether alive or known only from fossils. The name is given by the first person (or people) to formally describe the species in the scientific literature. This isn't the same as the first mention of a new dinosaur. There are a series of rules which must be followed if a new species is to be considered to be correctly described. The main one is that the name must consist of two parts: a generic name (the first word of the name) and the species name (the second word). There may be more than one species in a single genus. In this case these species will have the same generic name, but a different species name. The combination of two names must be unique for every species of living things. There are also rules about how the organisms should be described. Some articles do not adhere to these rules. For example, the recent feathered bird-like dinosaurs from China were first illustrated (eg. in National Geographic) before they were formally described scientifically. Any name used before the proper description doesn't count as a new species. The rules about naming species of animals are called the International Code for Zoological Nomenclature (the ICZN). Similar sets of rules exist for plants, microbes, fungi, etc.. Other rules involve the fact that often a newly described species will later be considered to be the same species as an older species. In these cases the oldest name for the species is the correct name. This often happens in dinosaurs because species are often described on the basis of only a few pieces of the skeleton. For example, Allosaurus was described originally from a tooth, two dorsal vertebrae [a small part of the spine], and a phalanx [toe bone]. Later discoveries of other bones may have been described as a different species, and only later, when a whole skeleton was found, would it have been clear that they were, in fact, parts of the same animal. Similarly the correct name for the dinosaur Brontosaurus is Apatosaurus, which was used first for fragmentary material of the same dinosaur. The full name of a species, when used by scientist, usually includes the name of the person or people who described it, and the year of description (the name should also be italicised). The correct way to refer to the first known species of "Brontosaurus" is: Apatosaurus grandis Marsh, 1877.

Any name at all may be given to a new dinosaur species - it's up to the scientist describing it. If a very silly name is proposed, then the editor of the journal where it is published could refuse to publish it, but this is probably rare. Typical names refer to the geographical area where the species was discovered, unusual anatomical features of the species, the supposed habits of the species, or are a tribute to famous (usually dead) palaeontologists. Despite popular belief, organisms are not really named in Latin, but the names must be "latinized", i.e. the words must resemble Latin or have Latin endings. For example, they are often latinized Greek words, but can be latinized English, Chinese or any other language. A few example names and their origins are:

• Gallimimus bullatus - Gallus is the scientific name for the genus which includes the domestic chicken, mimus meaning mimic. So the generic name means "Chicken Mimic", the scientists who described this dinosaur obviously thought it looked like a chicken! Bullate means having a blistered or puckered appearance - this obviously refers to some anatomical feature of this dinosaur, but I don't know off-hand what! - probably some sculpture of the bones.
• Gilmoreosaurus mongoliensis - Gilmore was an American palaeontologist working in the first half of this century, and the ending saurus, meaning lizard, is the standard one for dinosaurs. This generic name means something like "Gilmore's dinosaur". The species name mongoliensis refers to where the species was found, in this case Mongolia.
• Iguanodon bernissartensis - Iguana refers to this type of living lizard, don is derived from the latin for tooth. The generic name refers to the similarity of the teeth to those of the Iguana. Bernissart is a town in Belgium where this dinosaur was found.
• Plateosaurus engelhardti - Plateo = large (Greek) and Saurus = Lizard (Greek).Engelhard is the paleontologist who discovered the fossil
• Shantungosaurus giganteus- Shantung is the area of China where the dinosaur was found, giganteus refers to its size!

The number of dinosaur species is not really known. This is because, as mentioned above, species are often described (named) on the basis of only a small number of parts of the skeleton, and may be the same as other described species. In short, many dinosaur species are so poorly known that it is not clear if they are true species or not. This problem exists in most fossil groups, and most or at least many species may not be true species. There are a total of 852 dinosaur genera (the taxonomic level above species, which may be a better representation of the number of true species, singular "genus") have been described, according to Dinogeorge's dinosaur website. Of these, at least 163 have since been shown to be invalid. A genus represents a small group of very similar species, for example, Tyrannosaurus is a genus, and T. rex is one species. Genera equate to the "kinds" of dinosaurs more than species do. Five other species of Tyrannosaurus have been described, but these are all somewhat doubtful. A complete list of dinosaur species is available as part of the University of Bristol's Dinobase, this list 1066 species - lots of information about dinosaur biology, classification, evolution and extinction are available there too. Other good links include: Dinoruss's lair, Dinosauria online and Dinosaurs Alive!, a site specifically designed for classroom use.

Hope this is of interest!
Yours,
Trevor Cotton

Palaeobiology Research Group,
University of Bristol.