ARE YOU A CAT-LOVER? If so, what follows may be of some interest. If you’re more of a dog person but have some background in the life sciences or natural history, read on. (And don’t be put off by the title, which is meant to lampoon an antiquated style of writing once found in stuffy scientific journals. This piece isn’t at all technical.)
By one estimate, 42 million households here in the USA have one or more feline occupants. If your household happens to be one of the 42 million and it so happens that there’s a pussycat of the tabby persuasion in residence, please go and find her or him at this time. We’re going to perform a little hands-on demonstration that requires a cat; ideally one with stripes. (Tabbies make great subjects but any breed with tiger stripes and/or spots will do.) If your kitty is presently snoozing, all the better; let the sleeping cat lie. For the purposes of our investigation an immobile, dead-to-the-world specimen is actually preferable. Asleep or awake, if a suitable feline is not readily available just whip out your phone and google “cat images.” Scroll until you come across a good close-up head shot of any striped version of Felis catus, the common house cat.
Now: observe your sleeping pet (or acceptable online image). Right above the subject’s eyes you will see two small, dark-colored patches of fur—to be more exact, parallel-sided or possibly lens-shaped vertical “bars,” each flanked by two lighter-colored bits. For reasons unknown these dark, slightly elongated spots mark the place where the cat’s eyebrow whiskers arise. In your run of the mill black-and-gray-striped tabbycat, the whisker-encompassing central portion is always black; in the orange or gray models, it may be faint or absent but if present will invariably match the cat’s overall color scheme. With tabbies, coat patterning on top of the head—that is, the area betwixt the cat’s ears down to the bridge of its nose—ranges from slender converging stripes to an almost solid black, brown, orange, or gray patch (again, depending on the cat’s overall color scheme). Regardless of pattern, the crown markings narrow and then end abruptly in the vicinity of the two dark-colored spots. This goes for gray tabbies, ginger tabbies, orange and whites…regular tabbies with white chests and bellies, Maine coon cats, plus a few exotic breeds like Bengals and Abyssinians. Worth noting: the eyebrow whisker-spots tend to be most pronounced in those domestic strains bearing a residual resemblance to the common housecat’s direct ancestor, the African wildcat—first tamed in the Fertile Crescent around ten-thousand years ago.
People who spend a great deal of time around cats eventually learn that most if not all stripy-coated individuals sport some version of the just-above-the-eye markings. But, after having noted their curious association with the eyebrow whiskers, it appears that even fanatical cat lovers give them little or no further thought. Here’s the thing: cat fanciers, even dyed-in-the-fur feliphiles, haven’t the faintest idea that those ubiquitous tabbycat markings are technically known as ocelli—“eyespots” to us regular folk. And there’s nothing random about our still half-wild pets having eyespots on their foreheads. They are in point of fact a survival aid; a special add-on bit of biological trickery whose function is to divert would-be predators. Lots of animals have them. (More on this in a moment.) Feline-style eyespots have presumably been around for millions of years; probably since shortly after cats were first invented, back in the Miocene epoch.
Back to the (preferably sound asleep) kitty that you have by now located. Look into their adorable fuzzy face while concentrating on those two spots. To help achieve the objective of this hands-on investigation, you will now be asked to deploy a useful visual technique—we’ll call it “defocalizing”—which consists of nothing more than crossing the eyes slightly; just enough to make everything slightly blurry. Anyone can do it! Defocalizing has the effect of expanding your peripheral vision, making it a cinch to spot movement within a large and complex field of view. It also facilitates distinguishing subtle or hidden patterns that are either inobvious or flat-out invisible when looked at directly. This nifty trick has been used since time immemorial by hunters, birders, field biologists, and, in all likelihood, by…guess who?
So. Cross your eyes slightly. Once you’re good and defocalized, look at those spots again. Now that the subterfuge has been pointed out, you should see a pair of wide-open eyes staring straight into yours: eyes with vertical pupils flanked by paler-colored irises—unmistakable, unambiguous cat eyes. (Assuming a live feline was not to be found and in its stead you’ve located a good head shot: using an index finger, block your view of the eyes so as to not obscure the eyebrow-spots…defocalize…and voilá!)
What you’re looking at is a cunning deception—just one of many forms of defensive mimicry. Mimicry, like camouflage, is a passive means employed throughout the animal kingdom to help avoid injurious—possibly fatal—interactions with other organisms. There are a number of distinct, named strategies but I will mention only the one at play here, automimicry, wherein one part of an organism’s body resembles another part. Automimicry is used to great effect, for example, by the hairstreak—a small butterfly with delicate “tails” that project from the lower portion of its hindwings. These filamentous tails bear an astonishing resemblance to the hairstreak’s banded antennae. Together with other markings on the hindwing, they combine to produce a “false head.” Predators attacking this ersatz head might get a mouthful of wing instead of a tasty snack. Kitty’s counterfeit eyes are another textbook example of automimicry.
An astonishing array of animals have independently evolved eyespots. These include butterflies and moths, caterpillars, fish, snakes, lizards, birds, and mammals (with insects being the vast majority). Insect ocelli, however, don’t meet the criteria of being a form of automimicry as they tend to resemble eyes belonging to some much larger fictitious creature. Instead, the basic idea is to elicit a startle response that might throw off a predator, giving one or the other party an opportunity to make a hasty getaway. A classic example is the Io moth, which bears outsized, strikingly realistic-looking eyespots at the center of each hindwing. Ordinarily these false eyes are concealed but when threatened by a predator the moth spreads its forewings to expose them, instantaneously conjuring a downright scary visage out of thin air. In many instances, butterfly and moth ocelli are uncannily lifelike, often with strategically located white dots that artfully create the illusion of light glinting off a moist, black orb. At any rate—finned, furred, or feathered, being confronted all of a sudden by a pair of glistening, inscrutable eyeballs is going to get your attention. It’s easy to see how the ocelli ruse might stop an attacker in its tracks, even one that’s much bigger and more powerful than its prey.
What about cats, though? It’s fair to ask how having fake eyes right above their real eyes could be beneficial in terms of the cat’s survival. Let’s not forget that predators get predated, too—especially their young. So, one possible scenario: great hairy beast on the hunt stumbles upon a fast asleep cat but, seeing the mock eyes and assuming its potential dinner to be awake and alert, thinks twice or maybe thrice about taking on all those sharp teeth and claws. This is a fairly implausible set of circumstances given that it would require the potential victim to be in deepest slumber—doubtful for such a hyper-alert creature, especially one away from its den (or human habitation!) or at the very least hidden in a secure place where full repose is feasible. Another, more likely possibility: cat on the prowl passes beneath a predator waiting in ambush—say, one crouched on a limb or rock ledge or circling silently overhead. (In case you’re wondering: above ground ambush predators might include a larger feline species or, if the potential prey were one of the smaller cats, hawks, eagles, or owls.) And here’s where the real beauty of the subterfuge comes into play: from above, those sham eyespots appear to be gazing upwards, right into the lurking predator’s eyes. The savvy hunter, finding its cover blown, is unnerved enough to hold back. Or, shaken by being detected, unintentionally makes a sound that alerts the would-be victim, giving it time to flee or at least get into a defensive posture. Now: look down on your passed-out pet and imagine yourself a hairy beast about to pounce on its next meal. Get into defocused mode again and see the menacing glare of two wide-open eyes drilling straight into yours, just daring you to try. Keep in mind that predators will frequently forego a strike once they’ve lost the crucial element of surprise; going after prey that’s on the defensive, regardless of its size, is often deemed too risky due to possible injury.
So how is it that this eyespot-thing has managed to stay under the radar? Frankly, I’m shocked that it took me so long to figure it out. You see, I—ahem!—consider myself something of a cat expert; I’m familiar with the nictitating membrane and the tapetum lucidum…know of the carpal pad and the righting reflex…know what “flehmening” is and how it relates to the vomeronasal organ. With a lifetime of experience behind me, I can assess any cat’s mood in an instant through its facial expression, tail movements, and overall body language. I’ve been known to inform people, in a mock-ostentatious tone (but only half joking), that they are talking to a certified Cat Psychologist. So I’m a bit miffed that it took me a good half-century to spot the eyespots, particularly because they’ve been—pun intended—staring me in the face all this time. Clearly, I’m not alone here; no one else seems to have noticed them, either. This, I find hard to believe. Nonetheless, thus far I’ve been unable to locate a single reference to ocelli in cats—online, or in any of the several books about camouflage and mimicry that I’ve read.
Now that you, too, know that many cats wear a set of false eyes on their foreheads, here’s one more bonus item; a bit of feline minutiae vis-à-vis the old chestnut about cats “sharpening their claws.” Which, it turns out, is erroneous—a widespread misconception that has been promulgated for centuries if not millennia. The sharpening-their-claws fallacy, accepted the world over as gospel truth, falls into the category of those things we’re told as mere toddlers (“Look, Melanie! Fluffy’s sharpening her claws!”) that we accept unquestioningly and in due course pass on to our children. And they to theirs. Well, cats are not—I repeat, not—honing their claws when they’re up on hind legs, gleefully shredding your sofa or out in the backyard going after small trees. Cats engage in this quintessentially feline behavior when they’re feeling sassy and fixin’ to go on a tear…maybe after a good long nap when, all of a sudden, they’re chock full of energy. Ever notice that devilish gleam in their eye as they assault the upholstery while you’re yelling Stop it! Stop it! and being completely ignored? Well, what’s going on here is that kitty is feeling really really good—ready to rock and roll!—and Nothin’ feels better than arching the ol’ back and stretching out the toes! Ahhhh!
Everybody knows that as cat’s claws grow, the innermost layers periodically slough off leaving fresh, sharp tips behind. Without a doubt, those weird little curved “nail clippings” are shed during routine scratching sessions. But note: you don’t find them liberally scattered at the foot of their favorite scratching-post, the now tattered and frayed corner of your sofa. No. Instead, every so often you find one stuck in the carpet or laying on the kitchen floor by the food bowl. Think about it: those extraordinary retractable digits of theirs are kept folded up all day long, like toes crammed into too-tight shoes. Imagine how exquisite it must feel when they sink them into the pliant fabric of your BarcaLounger’s armrest and give ‘em a nice long strrrretch!
So here’s the skinny: Tiger/Cinderella/Peaches is not “sharpening” his or her claws. Their claws don’t require maintenance. It happens automatically. What they’re doing is more or less the feline equivalent of knuckle cracking—an annoying habit.
©2024 Tim Forsell 28 Jan 2024
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