In short, nope!
Neanderthals get their name from the Neander Valley (or Neandertal in German), near Dusseldorf in Germany. This valley is where the first Neanderthal fossils were found, around 150 years ago.
|OMG, it's a Neandertal baby!! |
Or is it a Neanderthal baby...?
common I get the impression...
Neanderthals' taxon is Homo neanderthaensis, with the 'th', so I guess purists could argue that it's better to spell it with the 'th'. But what is appropriate in language is defined by what people use (generally), so whichever!
'Thal' and 'tal' in the German are both pronounced the same, which reflects how some people (like me!) spell Neanderthal but say 'Neander-tal'. However, pronouncing the 'th' is totally common and often used in the English pronunciation of the species.
In short, say whatever, spell whatever... it's language! As I said, what is 'appropriate' is all about what people use, and in what situation. It's all about conventions, and there are conventions of using both :)