Copyright © 2016 by Thomas Gangale
Living as we do in a tropical climate, we have all manner of uninvited creepy-crawlies in our house: roaches, geckos, the occasional spider which can grow to the size of a human hand. Not a problem. I have only to chatter to my three cats, and all of them are at my side in a second or two, on station, on full alert. They follow my gaze, spot the prey, spring into action. Within seconds one of the cats takes down the prey and they stand down from the alert.
There are several theories as to why a cat utters chattering or chirping sounds when staring at prey such as birds or insects. One idea is that it may be an expression of the frustration the cat feels from not being able to immediately get to the prey. Another theory is that the chattering is a reflex motion in anticipation of delivering the killing bite to the prey’s neck. Still another explanation is that it is how the cat controls his over-the-top excitement at spotting the prey.
The most logical explanation of chattering or chirping is that it is a form of communication which has some survival value, else probably the behavior would never have evolved in cats. Starting from this premise, one must ask, with whom is the cat communicating, and what information is it communicating? The context of the communication is important; it occurs while the cat is hunting prey.
If the conventional wisdom is correct that cats are strictly solitary hunters, why would a cat communicate anything to another cat during a hunt? An alternative explanation of chattering or chirping as communication is that cats are communicating to their prey, that they are mimicking the prey to lull it into a false sense of security. This idea rests on at least two assumptions, both of which are false: first, that all of a cat's many and diverse prey species (insects, arachnids, reptiles, birds, rodents, et cetera) are social and that they feel safe among others of their kind; and second, that all of a cat's various prey species have a high probability of being fooled by the cat's mimicry. This latter assumption cannot be correct, since a cat's chattering or chirping sounds are the same regardless of which prey species is in its sights. Also consider that cats have been preying on these same species for millions of years, yet their supposed mimicry is far from high fidelity. If it sounds vaguely like some particular species of bird, it is not credible that the same sound would somehow be comforting another avian species whose call is distinct. Moreover, why would a mimicked bird call have a calming effect on a rodent? It is scarcely credible that a mouse thinks to itself, "I can't tell whether that sound is a bird or a cat imitating a bird, so I'll just ignore it." Meanwhile, evolutionary theory suggests that the prey species extant are the descendants of individuals who survived because they were not deceived by the cat's alleged ruse. There should have been an evolutionary race between the cat's increasing ability to more accurately reproduce the sounds of its diverse prey species on the one hand, and the prey's increasing ability to detect the intended deception on the other hand. All things, considered, it is improbable that a cat's chattering or chirping fools any prey, so there must be a better explanation for the behavior. Finally, the mimicry theory of these vocalizations requires a separate explanation of the furious tail-flicking which accompanies them, since such body language is clearly not any sort of mimicry.
Suppose that the conventional wisdom that cats are strictly solitary hunters is incorrect. This would suggest the possibility that the cat is attempting communication with others of her kind during the hunt, both vocally and via silent body language. Since the cat's best hunting strategy is stealth and surprise attack, communication may be a secondary strategy for when stealth alone will not suffice to achieve a kill. This explains chattering or chirping, as well as the tail flicking, as a survival-strategic behavior. The cat is neither expressing frustration, nor practicing a biting action at which it is already supremely proficient, nor celebrating an anticipated kill, nor mimicking its prey; he is calling for backup.
A call to the hunt can be explained even in a single-cat household. Ask not for whom the cat chatters; the cat chatters for thee to get thyself into the hunt. Your cat may regard you as something of a retard, standing around sighing, "Aw, isn't she cute," but you are a member of her social unit, and she wants you to get with the program.
An argument against cooperative hunting as an explanation of chattering or chirping, as well as of tail-flicking, is that the cat may end up sharing some of the kill with another cat, or it may even end up with no share at all; however, this is not a conclusive refutation for two reasons. First, cats are social, so a kill resulting from a cooperative hunt benefits the social unit as a whole, and in the long run the social distribution of such kills should benefit most of the members of the social unit. Secondly, cats are recreational hunters; they kill for sport as well as for food. Since hunting is not always a matter of survival, losing the benefit of the kill to another cat is often inconsequential, thus sharing, even when not entirely consensual, is unlikely to provoke a confrontation beyond some "cat cussing."
In most hunts, solitary stealth has a higher probability of success than collective stealth; with an increasing number of hunters, there are more chances for the prey to detect one of the hunters. This explains the cat's preference to hunt alone. However, its social nature, together with its nature as a recreational hunter, suggest that cats may have a flexible hunting strategy which includes cooperation as appropriate to the target of opportunity. Being far less common, humans are far less likely to observe such cooperative hunts; however, absence of evidence is not evidence of absence.
Dylan tried jumping from the bed for a gecko on the ceiling, but he couldn't quite get it. I chattered to him, which is our signal to each other that there is prey within reach. Of course he already knew that, but the point was to tell him that I also knew. Move, shoot, communicate. So when I picked him up, he was ready for that, tracking the target as I lifted him to the attack position. Then I launched him to the ceiling in a quick motion, and Dylan came down with the gecko in his mouth. It was middling size, so it was gone down his throat before I could look Dylan in the eye.
Thomas Gangale's Dogs and Cats: Stories, Songs, and Images
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