Here is TSRM's discussion of a case that is quite similar to the FAPs case, so I'll discuss it here:
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.First of all, this case is much like the stickleback case. "Detects electric field of type F" is like the "detects red body of type R" and "takes to be an edible thing" is like "takes to be a male stickleback". (This is why I place the post here.)
Second, "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" The claim of "no intelligible sense" seems to me to be a bit strong, but it is probably right that just because a shark can (directly) perceive "edible" does not mean that it can (directly) perceive "inedible". But, this is largely a misdirection on TSRM's part. It will still turn out, I shall argue, that in the "non-standard" environments (i.e., in the experimental manipulation), the shark has the false perceptual belief that there is something edible below. But, how can the shark pick up the information that there is something edible below if there is nothing edible below? That's what the critic of EP is driving at.