The fossil of a dinosaur was first discovered in England in 1824. Since then, the group of dinosaurs has increased to 1,047 species, but some paleontologists do not agree with this figure, such as Michael Benton, of the University of Bristol. Many of the denominations of new species have been made based on a few bones, without analyzing their similarities with other known species. For this reason, and as a result of competition in obtaining and selling new fossils, about 500 species have not been correctly described. According to experts, half of the species of dinosaurs are uncertain.