The Ancient Near East list defines this area as follows:


     ANE is a mailing list on topics and issues of interest in Ancient
     Near Eastern Studies, from the Indus to the Nile, and from the
     beginnings of human habitation to the rise of Islam. It is intended
     to provide a medium for discussion among scholars and students
     actively engaged in research and study of this broad field.

With regard to mass migration, it is possible, given the research,
that the environment and food resources played a part, as after the Irish 
potatoe famine.  Similarly, any disruption among empire builders like the 
Ottoman or British or Roman Empires might cause conflict or 
alternatively, integration with another culture - any or all of these 
might be responsible for unrest and movement and each area would 
presumably have to provide its own evidence of the root cause.

Some food for thought :)


P.S. Just seen David Connelly note on Misletoe:
     Review of Economic and Environmental Changes during the 4th and 3rd 
     Millennia BC -Association for Environmental Archaeology (AEA), 25th 
     Anniversary Symposium in Bad Buchau, Southern Germany, 2nd-5th 
     2004 .
Climate input from the Assoc.for Environmental Archaeology might be quite 
on this subject!

>Simon Kidner wrote:
>>  But the OED dates its first usage to 1869
>> and defines it as 'The south-eastern part of Europe; the Balkan
>> States together with Asia Minor.'
>> So, to reiterate Bill, where did it come from, and where did it go?
>I think "The Ottoman Empire" is the answer to both questions.
>John Briggs