How many types of dinosaurs are known?

[music fades in]

Welcome to CoreFacts, where we're always short on time and big on science. I'm Jessica Robertson. Today's question is a good one.

How many types of dinosaurs are known?

Approximately 700 species have been named. However, a recent scientific review suggests that only about half of these are based on fairly complete specimens that can be shown to be unique and separate species. Also, even if all of the roughly 700 published species are valid, their number is still less than one-tenth the number of currently known living bird species, less than one-fifth the number of currently known mammal species, and less than one-third the number of currently known spider species.

The dinosaurs species identified are placed in about 300 valid dinosaur genera. Recent estimates suggest that about 700 to 900 more dinosaur genera may remain to be discovered. Most dinosaur genera presently contain only one species but some have more.

And now you know. Join us again every weekday for a new CoreFact. For other CoreFacts, or for CoreCast, our in-depth science podcast, go to usgs.gov/podcasts. If you'd like to have a question featured on our show, give us an email at corefacts@usgs.gov or a phone call at 703-648-5600. Remember, long distance fees do apply.

CoreFacts is a product of the U.S. Geological Survey, Department of the Interior.

[music fade out]