Languages are birth or die gradually. How time of birth and death of a languages (e.g. Avestan, Parthian, Median, ...) are estimated?
In a broader sense when we say that a new languages was birthed of or a live one died (extincted)?
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Sign up to join this communityLanguages are birth or die gradually. How time of birth and death of a languages (e.g. Avestan, Parthian, Median, ...) are estimated?
In a broader sense when we say that a new languages was birthed of or a live one died (extincted)?
Well it's hard to tell when a language is 'born' because it often develops from another older language. I guess you could find a "date of birth" for a constructed language maybe. As for language death, well it could be when the last living speaker dies, taking the language with them. Another theory would be that a language dies when it's second last speaker does, because the last remaining speaker can not use that language with anyone, I.e. it is not a means of communication any more. If you wan to know more about language death then you should consult Crystal (2002) Language Death.
Language is a continuum, and not something that has an absolute, well-defined beginning (or end, for that matter).
Think of a language like you would a species of animal or plant. There was no first human, or mouse, or giraffe, it has been a constant process of evolution. What we can see, however, is that at given intervals, there is a noticeable difference between how these creatures acted and looked, and when others broke off from the "main" line.
Language is exactly like this. We can look at English from 500 years ago and notice how different it was, but if you were living at that time, from day to day, the change wasn't noticeable.
As such, I don't believe any language was "born", but that this is rather a metaphor for the earliest time at which a language was evidentially distinct from its most recent descendant. We can look to history for clues about more abrupt changes, though.
Language death is similar. In terms if Middle English dying out and being replaced with modern English, that was just the result of evolution. Then you can look at language that was wiped out by conquest, and look at how the natives speak the language of their conquerors. In Ireland, the way English is spoken, even by those who do not know any Irish, has traces of Irish in it (the classic 'at all, at all' is a calque of 'ar chor ar bith', for example). In that case, is the language really dead (FYI - Irish is not by any means a dead language).
When we look at recently extinct languages, they are lost to proper study when the last speaker dies, and if they have not been recorded, they may be lost forever.