Everybody loves dinosaurs, which might explain why other prehistoric reptiles are often mistaken for the extremely popular 'terrible lizards'.
Dictionary definitions don't make things any easier by mentioning that dinosaurs mainly lived on land. Spinosaurus was semi-aquatic, and this discovery – that the planet's largest carnivorous dinosaur (and star of Jurassic Park III) spent most of its time in water – could make it even more difficult for the public to distinguish between a swimming dinosaur and marine reptiles such as plesiosaurs.
Flying reptiles – pterosaurs – are regularly mislabelled by the media, confusion that might stem from knowing that birds evolved from dinosaurs. (To tell them apart, read my companion piece to this post: Dinosaurs, Pterosaurs And Other Saurs – Big Differences).
Some journalists seem to be genuinely ignorant of the fact not every extinct reptile was a dinosaur. But based on my past experience working for a popular science magazine, I suspect others might be making a deliberate mistake, a little white lie used to tackle the following problem:
Many people who are interested in dinosaurs will also be interested in other prehistoric reptiles, but words like 'pterosaur' and 'plesiosaur' aren't as recognisable as 'dinosaur'.
So how do you get those people to notice something they might otherwise miss? Simply put: What do you call interesting prehistoric reptiles without using the word dinosaur? I call this 'the dinosaur dilemma'.
It's possible to reduce this problem by adding 'dinosaur' in a subtle way: the American Museum of Natural History entitled an exhibition 'Pterosaurs: Flight in the Age of Dinosaurs', for example, while websites can include the word in the URL address to improve search engine optimisation (far more people search Google 'dinosaur' than other saurs). But this keyword strategy doesn't solve the problem for news headlines, where space can be extremely limited.
Advantages of Paleosaur
Here's my solution to the dinosaur dilemma: 'Paleosaur' (or 'Palaeosaur' for all you non-Americans and search engines). There are several reasons why I think it works.
- Easy to understand. Even if someone has never seen or heard the word before, they can guess its meaning: 'paleo' means prehistoric or ancient and 'saur' is associated with reptiles, thanks to dinosaur.
- Flexibility. When used as a collective term for multiple reptile groups, the word adapts to the context – such as collectively referring to ichthyosaurs and plesiosaurs as 'marine paleosaurs'.
- Rolls off the tongue. Unlike 'pterosaur' and 'ichthyosaur', the spelling of the word is phonetic so there's no barrier to pronunciation.
- Short and concise. The word expresses extra information in just a few letters – 'paleo' implies extinct – making it ideal for headlines.
The word 'paleosaur' would be used in the same way zoologists use 'megafauna' to describe any large animal or animals. The term doesn't relate to a specific group or point in time: megafauna can include anything from the mammoths of the Pleistocene epoch to modern-day Californian condors.
Paleosaur is primarily designed to be a colloquial term used by journalists and the general public, but could also be useful to scientists, providing a convenient shorthand in academic papers, for example.
How could 'paleosaur' become a popular term? The word can catch on if the media takes a risk and tries using it. Another way is for an author to use 'Paleosaurs' as the title of a book that becomes popular.
Although paleosaur doesn't refer to a specific group of reptiles, in some ways the term is less ambiguous than 'dinosaur', which creates confusion when mixing formal and informal expressions. The phrase 'birds evolved from dinosaurs' is correct from a dictionary definition of dinosaurs being extinct, but it's incorrect from an evolutionary perspective because birds are dinosaurs.
Arbitrarily excluding members creates what scientists call a 'paraphyletic' group, the equivalent of deciding not to invite a troublesome relative to your wedding – it doesn't remove them from a family tree. Birds are the estranged cousin of the dinosaur family, and so paleontologists clarify the relationship by referring to birds as 'avian dinosaurs' and most extinct reptiles as 'non-avian dinosaurs'.
Problems with the solution
There is one complication with 'paleosaur'. In the early 1830s, British naturalists Henry Riley and Samuel Stutchbury found fossils from a dinosaur that they called Paleosaurus, which is now known to belong to Thecodontosaurus (the fourth prehistoric reptile ever discovered, which was found near where I live in Bristol).
Later, the genus Paleosaurus was used to name members of an ancient group of crocodile-shaped reptiles, the phytosaurs.
Most of those Paleosaurus species are now considered invalid. Professor Michael Benton, a vertebrate paleontologist at the University of Bristol, tells me that "one species has been re-identified as possibly a phytosaur, and the other as some indeterminate archosaur". (Archosaurs are 'ruling reptiles' – a group that includes pterosaurs, dinosaurs and crocodiles.)
Given that the name Paleosaurus has become redundant, I think it's fair to adopt 'paleosaur' for a useful purpose.
Fossilized skull of a phytosaur from the Petrified Forest National Park (Image CC BY 2.0: Park... [+]
Paleosaur seems like such a simple solution to the dinosaur dilemma that I'd be surprised if it hasn't been proposed before. (I couldn't find anything relevant through Google, but it might have previously been suggested in a dusty academic journal somewhere – let me know if it has.)
Are there other good candidates for a collective term? Mesosaur might work. Dinosaurs, pterosaurs and other saurs all lived during the Mesozoic Era – the age of reptiles – 252 to 66 million years ago. The disadvantage of mesosaur is that I predict most people wouldn't be able to guess what 'meso' means. The pronunciation of 'mesosaur' is ambiguous too (is it 'messo' or 'meezo'?) and doesn't sound nice. (Word nerds: Paleosaur trips off the tongue because the 'L' in 'paleo' is a liquid consonant.)
Not everyone will agree that paleosaur would work. Some might argue that a new word would only create further confusion amongst the general public. Others might say that if we just keep using words like pterosaur, people will eventually learn them. I was interested in what experts think, so I asked an eminent paleontologist.
"A fun idea," says Professor Michael Benton, but notes that 'paleosaur' wouldn't make it any easier for people to distinguish between prehistoric reptiles. "We'll always have to explain what is and is not a dinosaur."
That's a good point, and I would counter that by saying that a simple slogan can capture the public imagination and become a vehicle for a more technical term. The nickname 'the God particle' probably helped generate interest in the Higgs boson, for instance, and paleosaur could introduce people to articles containing words like 'pterosaur' until they become as familiar as dinosaur.
Benton also says that ignorance amongst adults can even be a good thing. "It gives kids such a sense of superiority that they know plesiosaurs aren't dinosaurs, although their parents don't know this useful fact!"
On the balance pros and cons, I believe 'paleosaur' is a good idea. The word isn't specific, but it's better than being wrong. Let me know what you think in the comments.
Lastly, to illustrate the benefits of an easy-to-understand name for all prehistoric reptiles, I'll leave you with this highly realistic future scenario, in which a member of the public bumps into a palaeontologist at a disco.
LOUD MUSIC
Public: Hi!
Scientist: Hello.
AWKWARD DANCING
Public: So what do you do then?
Scientist: Oh, I study paleosaurs.
BRIEF PAUSE
Public: Is that like dinosaurs?
Scientist: Yes, and other prehistoric reptiles.
BOTH SMILE
Public: That's so cool!
Scientist: I know.
THEY KISS
Because everybody loves dinosaurs.
Read: Dinosaurs, Pterosaurs And Other Saurs – Big Differences
