In Varieties of Meaning, Ruth Millikan distinguishes intentional signs from other natural signs. According to her, intentional signs are those natural signs which are purposefully produced for use by sign-users. Being selected by evolution for leading to such sign-use suffices for the production being purposeful within Millikan’s framework. Millikan then goes on to restrict her use of the concept “intentional sign” within the book to cooperative intentional signs (cf. Millikan 2006: 73-74).
Having audited a class by Dennett - he used the example in at least three different sessions - I could at this point in Millikan’s book not help but wonder whether the stotting behaviour of certain animals, such as gazelles, counts as a cooperative intentional sign. I am assuming here the theory that this behaviour is a signal from prey to predator of fitness, in this case being able to run fast or something of the sort, along the lines of the evolutionary theory of signalling (see Skyrms 2010). Under that assumption it is clear that this is an intentional sign as it would have been purposefully selected for being interpreted by the predator. It would be purposefully produced for sign-use.
But is stotting cooperative? I am going to say yes, for the following reason: As an honest signal it is beneficial for both prey and predator. They both avoid wasting time and energy on a race which the prey would win. It is for the benefit of both that the signal is send and interpreted. That being said, the animal agents find themselves in an adversarial situation. Millikan writes that “[a] cooperative intentional sign will always stand midway between two systems that have been designed to cooperate with one another” (Millikan 2002: 73). While not entirely clear, this statement does not sound as if she had stotting prey in mind. While I doubt it matters for Millikan’s specific purposes, the example serves as a reminder of the subtle difference between different notions of cooperation, especially when one goes beyond adult human agents.
Millikan, R. G. (2006). Varieties of Meaning: The 2002 Jean Nicod Lectures. Cambridge, MA: MIT Press.
Skyrms, B. (2010). Signals: Evolution, Learning, & Information. Oxford; New York: Oxford University Press.