McBrearty and Brooks (2000) suggest that behavior drove the anatomical changes seen in the archaeological record, and that behaviors developed gradually over time and space. They list four characteristics that are inherently modern behaviors:
[1] Abstract thinking, the ability to act with reference to abstract concepts not limited in time or space. [2] Planning depth, the ability to formulate strategies based on past experience and to act upon them in a group context. [3] Behavioral, economic and technological innovativeness.[4] Symbolic behavior, the ability to represent objects, people, and abstract concepts with arbitrary symbols, vocal or visual, and to reify such symbols in cultural practice [McBrearty & Brooks 2000:492].
It is this last trait (symbolic behavior) that the majority of scholars define as modern behavior (Nowell 2010: 441), however some like Mellars (1989) place emphasis on technological innovativeness. The archaeological evidence of these traits can be divided into four groups: ecology, technology, economic and social organization, and symbolic behavior. Ecology consists of extending range usage and increasing diet breadth. Technology consists of “use of new materials such as bone, standardization of tool forms, evidence of hafting, and composite tools; the development of specialized tools” (Nowell 2010: 440). Economic and social organization