A good dinosaur joke is "What do you call a blind dinosaur? Doyathinkitsaurus." A good dinosaur joke for commuters is "What do you call a dinosaur traffic accident? A Tyrannosaurus wrecks." An anti-humor joke involving dinosaurs is "Which dinosaurs can jump higher than a house? All of the dinosaurs; houses don't jump."
Scientists estimate that over 71 percent of all species of dinosaur are still unknown. This evidence contradicts evidence that dinosaurs were in a decline towards their extinction, which helps enforce that their extinction was caused by a rapid event. However, several scientists claim that categorizing partial fossils may lead to researchers double counting.
In Victorian times, palaeontologists were prone to claiming that every bone or tooth came from a new species of dinosaur found. After taking these composite pieces and combining them, palaeontologists were able to reduce this amount down to approximately 500 species. Since the 1990s this number of dinosaur species has been growing. Palaeontologists estimate that 14.8 new species are discovered every year, whereas in the 1980s, only 5.8 species were found every year.
As of 2014, the U.S. has the greatest variety of dinosaur fossils, though scientists acknowledge that the proper study in other countries could skew this number. The country with the second greatest dinosaur collection is China.