Megalosaurus, ichthyosaurus, stegosaurus, Tyrannosaurus rex — most nine-year-olds will be very familiar with the fact that -saurus -ˈsɔːrəs is a common ending for the names of dinosaurs.
Young dinosaur enthusiasts who live in England and other nonrhotic places are thereby well primed for jokes such as
— What do you call a short-sighted dinosaur?
— A “do-you-think-he-saw-us”!
where of course saw us is pronounced -ˈsɔːrəs with intrusive r.
Obviously, this joke would tend to fall flat in north America.
Rhotic speakers have to console themselves with lamer jokes like
— What did the dinosaur say after the car crash?
though I suppose even that one wouldn’t work for people who have distinct FORCE and NORTH vowels.
They’ll have to be content with
—What do you call a dinosaur that smashes up everything in its path?
A correspondent saw some interesting dinosaur money boxes in a gift shop in London. Each dinosaur was given a name formed from a child’s name plus -saurus, with the pronunciation shown in an ad-hoc respelling system.
What is interesting is that the respelling system assumes intrusive r as a matter of course, so that “saw us” is seen as an adequate indication of how to pronounce -saurus. My correspondent comments that this produces the wrong pronunciation for a rhotic speaker like him.
Clearly this gift shop is not going to be catering for the Scottish, Irish or American markets.