|MadSci Network: Science History|
As far as I know, and as far as my search on the Internet and local library went, I don't think Hitler did any experiment like that, gruesome as it may seem. It also seems unlikely to me because Hitler had access to the best doctors in Germany at the time, and if he was serious about such an experiment he would not have let them die immediately, at least I don't think he was that stupid. However, he did do eugenics experiments on Jewish and Gypsy children, among other things trying to change eye color and other experiments which are very awful to discuss. But he seems to have been repeating Lamarck's mistake, that acquired traits (like modified eye color) can be inherited.
However, there was an experiment in antiquity, done by the Egyptian king Psamtik I in the 7th century BC. The story was told by Herodotus the Greek historian. What he tried to do was to isolate two children from the rest of civilization, which, as an absolute monarch, he could do easily. They were to be raised by a shepherd who was not to speak to them or allow them contact with other people. The assumption was that the language they would speak would be the first language of humans.
After about two years, the shepherd heard them say 'bekos', which was the word for 'bread' in the language of the Phrygians, who lived in Asia Minor. Thus he concluded that the first language that humans ever spoke was Phrygian.
There are several sites that give information on his experiment. Here's a short note on it. Here is another one, scroll down to 7 BCE, though I think they got the date wrong. This is a rather inhuman suggestion called 'my baby project'; which I certainly do not approve of. The previous link allows readers to comment on it, and the second last comment (as of this writing) gives some historical examples. Intriguing, to say the least. You could also search in your local library for more information on this.
Of course that is not a real scientific experiment. The children could have heard the shepherd's sheep and imitated them, or simply made a random sound. In anycase, our far distant ancestors weren't all speaking Phrygian. The origin of language is shrouded in mystery, and linguists to investigate it need to rely on archaeological, lingual, and other evidence. I'm not a linguist, so I can't tell you here. But the good folks at the Ask a Linguist service can possibly tell you more. You could also search in their archives. It's an ask-an-expert service which is very similar to MadSci, so I'm pretty sure you know how it works (=.
If you're interested in the immense variety of language in the world in general, why not check out the Ethnologue. Interesting place.
I guess that's all I have to offer. Hope that I helped answer your question. Keep on asking!
Thiam Hock "Speech-maker" Tan
Try the links in the MadSci Library for more information on Science History.