This issue of behavioral modernity is something I have never really accepted from mainstream Prehistory and Anthropology. In this conceptual paradigm or intellectual fetish (whatever you prefer to call it), humankind almost suddenly emerged from the amorphous shadows of what we could call (by contrast) behavioral primitivism and began being us, maybe when they decided to create some perdurable art like that we can find in the caves of Southwestern Europe and the related technologies defined as mode four (or blade-based stone industries or Upper Paleolithic in the narrowest possible sense).
The reference is silly and eurocentric but very real in these academic fields. As of late, the finding of other, more ancient and not really European expressions of prehistoric artwork, notably in Palestine, North Africa and South Africa (in this chronological order per the available data) allowed the concept to escape its original sin of Eurocentrism somewhat but, regardless, is the concept real?
A new study by John J. Shea, published in Current Anthropology (pay per view, discussed at Science Daily), challenges this, already quite shattered perception of some almost miraculous transition towards behavioral modernity on scientific grounds: Shea analyzes the rather well documented early Humankind in East Africa between 250,000 and 6000 years ago, and finds no linear pattern of evolution but rather an outstanding array of nonlinear diversity.
From the news article:
A systematic comparison of variability in stone tool making strategies over the last quarter-million years shows no single behavioral revolution in our species' evolutionary history. Instead, the evidence shows wide variability in Homo sapiens toolmaking strategies from the earliest times onwards. Particular changes in stone tool technology can be explained in terms of the varying costs and benefits of different toolmaking strategies, such as greater needs for cutting edge or more efficiently-transportable and functionally-versatile tools. One does not need to invoke a "human revolution" to account for these changes, they are explicable in terms of well-understood principles of behavioral ecology.