Alexander Marshack Harvard University
The papers at this conference on animal cognition explore selected, measurable or observable aspects of species memory, problem-solving capacity and neurological function. To that extent they are inquiries into the range and variety of species potential capacity. The capacities and behaviors being studied and measured, however, do not represent the range of adaptive capacities and behaviors used in the wild or that range of potential capacities available to a species, of which only a part can be used in any temporal context. In biological evolution, natural selection probably occurs as much for the range of "potential variable capacity" as for the structures of morphology and the patterned structures of species behavior.
Cognition itself represents a particular aspect of species adaptive capacity, that aspect which is not dependent on genetically coded or programmed behaviors but on a variable, if constrained, neurological response to the phenomena, patterns and structures of the real world. Potentially variable adaptive capacities and systems exist, of course, at the simplest evolutionary levels but, with development of the chordates, vertebrates, mammals, and primates, these become increasingly complex, variable and specialized. Given sufficient functional data, a species can probably be described and defined as much by the nature and range of its potentially variable capacity and behavior as by the more traditional categories of morphology and observed patterns of behavior in the wild. The problem is crucial to the following discussion of hominization as an aspect of natural selection for an increase in the specialized "potentially variable capacity" of an early pongid.
If the process of hominization, beginning some five or more million years ago, represented the branching of a potentially now species and the incipient development of now modes or levels of adaptive behavior, then the range of cognitive capacities involved must have been derived and