:::wow great debate ..both sides have very valid views..i am a retired Archaeogenetics and do agree that language enabled our ancestors to leave Africa, however the reason for the migration is most likely due to  climate change that resulted in loss of subsistence. This forced migration to find food, as most of Africa became a desert.  Anyways dont wish to add anything to the article, but you guys might like to watch this documentary that talks about this topic >Journey of Man: A Genetic Odyssey (movie)  - by  Spencer Wells -  PBS and National Geographic Channel, 2003 - 120 Minutes, UPC/EAN: 841887001267 > that is based on this book >Journey of Man: A Genetic Odyssey (book)  - by  Spencer Wells - Princeton University Press, 2002 (Digitised online by Google Books), ISBN 0812971469.....