Lingua ex Machina: Reconciling Darwin and Chomsky with the human brain - William Calvin and Derek Bickerton offer three ways for getting from ape behaviors to syntax. They focus on the transition from simple word association in short sentences (protolanguage) to longer recursively structured sentences (requiring syntax).
Proto-Language - An investigation of the earliest language of man. Comparative studies of the Proto-Language and various language families and languages currently considered to be isolated.
SAFi etymology. Indo-European, Nostratic or Eurasian ? - SAFi is a lexeme of several groups of languages such as Indo-European, Semito-chamitic, ouralo-altaic and niger-kordofanian. Its distribution consolidates historical linguistic theories of Nostratic or Eurasian roots previous to the Indo-European one (-7000 years).
Was Nostratic A Real Language? - On the family tree of languages, no one is quite sure whether Nostratic is a real branch or a just a shadow that has fooled some linguistic researchers.