Plus
|
|
|||
Meow! The intruding cat shrieks, spits, hisses and cowers. I fling a balled up piece of paper and issue dire threats to Dummy to break up the fight. As the other cat runs away, Dummy leaps in through the window, rubs his head against my foot and purrs loudly. Undoubtedly, our cat Dummy is a talker. Just as there are some people who talk more than others (and how!), some domestic pets talk more than others. Dummy has a large repertoire of noises, which he uses to communicate with us and to tell us how he feels. We, who have been trained well, understand him. A loud, long drawn out and repeated 'Mee-AAA-oo-www' 'Mee-AAA-oo-www' 'Mee-AAA-oo-www' translates into 'Where's my dinner? I'm hungry. Do not mess with me'; a medium 'Wa-aah' as he comes indoors is a 'Hi! I'm home!'; often, he responds to us with soft, short, gargly, noisy breaths which sound like 'mreeep'. Cat
talks Just as there are domestic cat breeds that are more talkative than others, wild cats are big talkers among other mammals. Unlike birds, who have colonised the skies and are therefore capable of escaping from predators by flying, most mammals do not advertise their presence in their environment. They are far too susceptible to becoming someone else's dinner, should they make a noise. The exceptions to this rule are those mammals who have nothing to fear from predators, like the mighty elephants, or predators themselves. And the most supremely adapted of all predators are the wild cats - the 'lean, mean, killing machines'. Cats are talkers who have no need for silence and therefore advertise their presence by a wide range of sounds. Experts estimate that in the family Felidae (wild cats, of which there are some 40 species) there are about 12 types of vocalisations or acoustic signals, ranging between 50 and 10,000 hz, although most cover only part of that range. I used to think that I was biased, as I think that Dummy has a far greater repertoire than 12 vocalisations, until I read recently that domestic cats have adapted their basic 12 vocal signals to a far greater range in order to better manipulate humans. Although it is not the same pitch across different species, the 'meow' is perhaps the most common cat vocalisation. The pitch of this 'meow' varies between species and has no relation to size. It seems strange that pumas of the new world who range in size from 36 -103 kg, have higher pitched meows than tiny black footed cats of Africa which weigh in at only 1.5 - 2.5 kg. In addition to variation among species, a 'meow' can vary within a species in duration, pitch and intensity. A low intensity, short meow seems to function as a close range signal, for friendly interaction, often between mother and young. High intensity, long drawn out meows seem to function as long-range advertisements for mates and to establish territories or in domestic cats, to convey a sense of urgency. Dummy often intensifies his meows and calls louder and longer if we delay in feeding him. Purring
sounds Amazingly, recent research has shown a link between purring and healing. Ultrasound, which is frequently used for healing damaged tissue, falls within the range of 20-200hz. The frequencies of purring (25 -150 hz) fall slap bang in these 'therapeutic range' of frequencies! The purr is also unusual because despite the domestic cat's 4000-year association with humans, nobody has yet understood how exactly a domestic cat purrs, much less any wild cat species. All anyone knows is that purring is produced while breathing. Most small cats (for example, black-footed cats, servals, caracals and cheetahs of Africa; ocelots, margays and jaguarundis of South America; bobcats and pumas of North America; and wildcats and lynxes of Europe) have been observed to purr. What most of us do not know is that some species of cats do not purr: the 'big cats' - lions, tigers, leopards, jaguars and snow leopards do not purr. Instead, most big cats except the Snow Leopard are known to roar. Between the back of the tongue and the voice box is a series of small bones called the hyoid apparatus. Roaring
success Roaring in big cats is different among different species. For example, leopards have a very distinctive hoarse, repeated rasping cough that sounds like a blunt saw at work. Roaring in leopards is therefore called 'sawing'. Sawing calls are made by male leopards to keep intruders off from their territories and usually, when one leopard calls, another answers. These sawing calls are distinctive, as the number of repetitions vary among individuals and could range from 2-30 beats per call. This is understandable - after all, we humans have distinctive voices and some speak faster than others, why not wild cats? Roaring in lions is different as several sounds are strung together in a sequence: lions start with soft, short moans, which escalate into high decibel roars at frequencies of 240 hz and then tail off into repeated grunts of 'huh,huh,huh'. No one who has heard two lions roar at close range can ever mistake their message, which is 'I am big, I am strong - don't you dare mess with me!' I was once walking down a corridor at the Smithsonian National Zoological Park in Washington DC and was directly in the centre of the path between two caged male lions who decided, at that moment, to roar at each other. Cowering against the wall, I shut my ears at the deafening and repeated bellows of 'aa-oo-uu-uu, aa-oo-uu-uu, aa-oo-uu-uu' from one male, answered a split second later by the other. Researchers have found that the roar of lions can be heard as far as five miles from the point of origin and one scientist noted that the body of his jeep shook because of the reverberations from the roar of a lion close by. Strangely, experts do not classify roaring in tigers as roaring because of the sequence and cadence of these calls, but their function remains the same: to advertise territorial possession. What is interesting is that recent research has revealed that tigers produce infrasonic, low frequency, deep sounds which we cannot hear. These infrasonic calls are unique because of their ability to carry over long distances through dense vegetation. This research ties in with earlier research which has shown that tigers maintain very large territories, so these calls serve the same purpose as roaring but over a much longer distance. Lions and other big cats roar to advertise themselves to members of the opposite sex ('Here I am, I am big and strong!'), and to claim ownership of their territories to members of their own sex (This is my house, don't you dare step in!'). The cheetah - the oddball of the cat family in terms of shape and hunting tactics - has also a peculiar long distance call, whose function is the equivalent to a lion's roar: a chirp, very like the sound of a bird! Just like the sawing calls of leopards are distinctive for different individuals, the cheetahs' chirps are also individually distinctive. Caterwauling
Hissing, spitting and growling accompany these antagonistic encounters. Often the 'victor' growls loudly while the loser (most often the intruder) screams or snarls in defence. Cats also hiss, spit and growl (increasing antagonism in that order) when confronted with something they don't like. A growl is an unmistakable signal that the cat is going to attack. Dummy has never hissed, spat or growled at us, but does not hesitate to show his antagonism to my brother's large and loving Labrador retriever. In friendly encounters, cats use low intensity sounds, which, in domestic cats, sound like soft, short, gargly, noisy breaths. In lions and leopards this gurgle may sound like a muffled sneeze, while in tigers, jaguars, snow leopards and clouded leopards it is called the 'prusten', which means snort or sneeze in German. Unlike the roar, the prusten, puff and gurgle function as basic, friendly, non-committal 'Hellos'. As a graduate student in the US, I had learned about the prusten in class but was rather sceptical about its function, until a captive tiger at the Smithsonian National Zoological Park, used to seeing me around at the end of a summer internship, said 'Hello' in Tigrese. What is remarkable is that the function is just a hello - no more, no less. The huge 500-pound tiger sat there, relaxed in its enclosure, just looking at me after having said hello, while I stood there rooted to the spot. Contrary to popular belief, cats become extremely silent when hunting. They are stealthy and often still and silent as statues before they leap on their hapless prey. Whenever I see Dummy sitting motionless in the garden, looking like Moses on a monument, I smell trouble, and I am always right, as seconds later, an unfortunate bird or squirrel lies dead on the ground. This silence is understandable, as cats, with the exception of the cheetah, are stealth and ambush hunters and advertisement of their presence to their dinner would be stupid. Cats also use extensive body language to communicate with other cats and with humans. Their postures, the position of their tails, ears and whiskers, all send a very clear message to whoever is watching. They also mark their territories (which often includes humans) by leaving scent marks or scratching. 'Mee-AAA-oo-www' 'Mee-AAA-oo-www' 'Mee-AAA-oo-www'. Sorry, it's dinnertime for Dummy and I've been summoned… |
||||
Copyright © 2001 Wijeya Newspapers
Ltd. All rights reserved. |
