"Thal" is cognate with the English word "dale."
The German book Die Neandertaler by Friedemann Schrenk and Stephanie Mu+ller was translated into English and published as The Neanderthals.
The lack of the “th” sound in German (”hello mudduh, hello faddah”) isn’t new, just the standard spelling changed. “Z” comes out “tz” when pronounced. English of course drives most people crazy I’m sure. :^)
I watch this guy for a few minutes every now and then, hoping to get the gist (hoping he gets to the point iow) before his lack of “th” runs me off.
https://www.youtube.com/user/ZONEofTECH