TSRM's Shark Example 3

Sharks electrically detect things to eat and things that impede locomotion (Kalmijn, 1974). An edible living thing such as a flatfish differs in ionic com• position from the surrounding water, producing a bioelectric field partially modulated in the rhythm of the living thing's respiratory movements. A flatfish that has buried itself in the sand will be detectable by a shark swimming just above it. Reproducing the bioelectric field of the flatfish artificially, bypassing a current between two electrodes buried in the sand, invites the same predatory behavior. The shark digs tenaciously at the source of the field departing from the site when the act fails to reveal an edible thing (Kalmijn, 1971). Now there is no intelligible sense in which it can be claimed that the source ought to have appeared inedible if the shark's perception were free of error and if the shark's perception of affordances were direct. In the niche of the shark 'an edible thing' and 'electric field of, say, type F' are nomically related. To predicate of the shark (a) 'detects electric field of type F' and (b) 'takes to be an edible thing' is not to refer to two different states of affairs, one (viz. (b)) that is reached from the other (viz. (a)) by an inference. Rather, it is to make reference in two ways to a single state of affairs of the shark-niche system. The linking of (a) and (b) is not something that goes on in the "mind" of the shark, as the Establishment would have it. The linking of (a) and (b) is in the physics of an ecological world, namely, that system given by the complementation of the shark and its niche.

Fourth, now, it is true, as TSRM note, that in their respective niches, these predicates are nomologically connected.  Thus, we cannot tell by looking at the behavior of fish in their standard niches what they are perceiving.  But by looking at how they behave outside their niches, we see that the fish are keying in on electric fields and red bodies, relying on the nomological connections.  And we can see that in the non-standard environment, when the shark takes something (the electric field) to be an edible thing, it is mistaken.  Similarly, in the non-standard environment, when the stickleback takes something  (a fake fish) to be a male stickleback, it is mistaken.  (Indeed, the non-standard conditions indicate how (a) and (b) are not the same.  (a) is true, but (b) is false.)  This is where EC seems to have trouble.  How can it be that the shark picks up the (Gibsonian) information that there is something edible in the non-standard case, when there is nothing that is edible?