Zoo cats and their domestic counterparts

The whole of the cat family is made up of around 37 different species.  I say around 37 because the ebb and flow of classification techniques means to some extent that there is constant questioning about one or another trait that may, or may not, change the classification of a few individuals within the family.

In essence the cat family throughout its lineage has a fairly similar feline body plan, with a few variations on the theme.  The long legged, shorthaired, Serval cat from Africa (Plate 1) compared with the short legged, furry Pallas cat from the steppes, though extremes apart visually, have their domestic equivalents.

By virtue of what it is, the domestic cat is the species that we most have regular contact with and the one that for many sparked an interest in their wild, exotic counterparts.

Personally, I most appreciated the presence of a domestic cat when I worked in a zoo, as a Senior Carnivore keeper; work that I consider myself greatly privileged to have carried out for some 23 years of my life. 

My whole day was spent in the presence of beautiful but dangerous and untouchable exotic cats.  The policy of the keepers in those days was to maintain the animals in their care to be as near to the wild as possible. Making pets of your wild charges was frowned upon as extremely unprofessional.

So only at nighttimes when I returned home, did I get the opportunity to safely feel at close quarters, the soft warm fur and languorous form of my feline companion.

I should say, however, that not all of the exotic cats I worked with were unapproachable and indeed some solicited contact with their keepers and seemed to enjoy the experience.

Tigers for instance utter a soft close contact vocalisation called ‘prusten’ that they make when they approach their keeper or another tiger with friendly intent. Prusten sounds a bit like the word iff, iff, iff repeated in quick succession and it is normally issued in short bursts. This call is use on occasions when the tiger approaches a well-liked keeper for a scratch.

However, unless you know the individual tiger involved it’s best not to take the risk. We did keep one female that uttered the friendly iff, iff ,iff call while rubbing close against the wire of her cage, soliciting contact.  She was, however, a rather mischievous individual. Once the keeper had been lured into sticking his fingers into her soft orange fur, she would unexpectedly snap at his fingers or strike out at his head with her huge paws. 
Numerous people with domestic cats experience this same sense of feline ‘fun’ but perhaps with less dramatic consequences. 

As you may expect many of the behaviours displayed by wildcat species can be observed in their domestic cousins.  A number of physiological similarities can also be seen throughout the cat family and indeed in their prehistoric relatives.  

In Leyhausen’s seminal work on cat behaviour (Leyhausen, 1979) he highlighted in the text and illustrated with photographs, the importance that cat whiskers played in cat killing behaviour.  Small cats when they are in close proximity to their quarry, use their whiskers to help them judge their distance from prey by orienting the whiskers forward. The whiskers are so sensitive that the cat can feel which way the fur or the feathers of their prey is lying, so that they can manipulate their way to the head end to start feeding.  Exotic small cats in zoos demonstrate the same use of whiskers even when presented with dead prey.

The use of whiskers in large cats is slightly more difficult to explain, however it is widely agreed that cats such as leopards use them when manipulating captured prey, to help them judge more accurately the movement and position of their prey, thus enabling them to execute an efficient kill.  One thing is certain, whiskers and their sensitivity have been important to the survival of cats for a long period of time. 

Sabretooth cats that became extinct in the America’s around 10,000 years ago, we think had sensitive whiskers.

The reason we think this is that the nerves from the whiskers of modern cats pass through the infraorbital canals in the skull, into the animal’s central nervous system. This canal is also present and well developed in the skulls of sabretooth cats (Turner and Anton, 1997). 

Did the sabbretooth use its whiskers in the same way as its modern day counterparts?  It seems likely that they must have been careful when using such highly developed canines and such accurate biting, aided by sensitive whiskers, would have been very useful. This is an amazing link between the wildcat species that live today, the domestic cat, and their extinct predecessors.

Scent and smell

Cat Houses in Zoological Gardens are, by their nature, quite smelly environments as you have the scent marking efforts of a number of individuals all concentrated in one building. I personally don’t find this odour in the least offensive, as I have spent a considerable part of my life enveloped in it. Indeed, as I travelled around the world visiting cat collections, I felt more at home with the musty smell of cats around me, than not.  Domestic cats, in particular, ‘intact’ Toms, produce powerful scent marking urine and as such are not always looked upon as the perfect full time house companion.

In zoos of course a vast majority of the males are intact and even efficient ventilation does little to ameliorate the musty atmosphere created. 

The scents that animals produce are chemical messengers and some are designed to linger. Some humans do find the scent of both domestic and exotic cats unpleasant and in the past, this has led to cat fatalities.   In the old days, when travelling circuses moved from town to town, the lion and tiger cages were cleaned to the detriment of the inhabitants. The animal carers would drench the wagons in strong smelling disinfectants to appease the sensitive noses of the visitors. Unfortunately, they used a disinfectant that contained phenols. Phenols are absorbed through the skin of the cat, even through the footpads and this often proved fatal. Other animals including humans have less difficulty with this chemical as they posses an enzyme that binds with phenol, allowing it to be excreted from the system. All cats domestic and wild are susceptible to this kind of poisoning. 

Both domestic and exotic cats use their scent in urine to mark their territory and it seems a shame that people often do not appreciate its function and go to such lengths to eradicate its presence.

Domestic cats are able to analyse scent by ‘tasting’ the smell. Cats, both wild and domestic, display a facial expression called the ‘Flehmen’ response. This facial grimace, with the lips drawn revealing the teeth, takes place when the cat is analysing scent. They pass fluid down the naso-palatine canals, the external openings of which can be seen just behind the upper incisor teeth in the mouth. The fluid in the canals is mixed with the air the cat has just sucked in and up into the vomeronasal or Jacobson’s organ in the skull.  The Jacobson’s organ is a double blind sac that is lined with sensory receptors that decode scent. Tiger, leopards and other wildcat species perform this behaviour as well as their domestic cousins.

Cats can have peculiar responses to perfumes that are used by humans. Some seem to be entranced by it, while others become highly excited.  One female Siberian lynx that I worked with, who was normally quite shy and aloof, found the smell of soap on the keeper’s hands extremely attractive and became friendly and seemingly spellbound in its presence. 

 Some human perfumes use the oily scent taken from the perineal glands, found under the tail of civet cats, as their base.  The reason for this was that civet scent binds very well with pleasant odours and stayed present on the human skin even after bathing. Civet cats of course, are not actually cats at all, but are members of the viverridae family that also contains the Genets and Linsangs.
 
The scent of civet is likely to mean something quite different to a cat than a human, though, as already mentioned some seem to enjoy the exposure. 
 
Both domestic and wildcat species use cheek and body rubbing to exchange scents and mark territory. Domestic cats often rub against their owner and it has been suggested that this is akin to rubbing against another more dominant cat. But cats do not limit their rubbing to other living creatures as they also rub against objects in their territory. In the home the side of the sofa, or leg of a chair might receive a quick rub, while in the garden a low branch or fence post may suffice. The beautiful Clouded leopard from South East Asia performs a rather elaborate cheek scent marking display. When the cat approaches a suitable marker, he opens his mouth wide and then slowly rubs the side of his cheek over the object to be marked. This marking behaviour sometimes varies as I have viewed these leopards lightly chew a branch, just crushing the bark enough to let the sap be exposed. The cat then slowly and deliberately rubs its cheek over the broken surface of the branch. It could be that by performing in this way that the scent is mingled with the sap and remains active for a longer period of time than those marks deposited on unbroken branches or twigs.

Litter trays

It may come as  a surprise to some people to know that litter trays used for domestic cats are also of value in the cat house. These trays cats are essential, not just for the sake of human hygiene but also to allow for cat ‘toileting’ behaviours. Old world small cats dig a hole in soft substrate to deposit their faeces in and cover it over. This behaviour is mostly limited to the core territory. On the periphery they deposit their faeces as a marker and do not cover it over.  Wildcat species in the zoo should also be provided with areas to defecate in, as they too like to cover it over. New World cats, however, though they seek out a soft substrate to defecate on, frequently do not cover it over regardless of its position in the territory.

The domestic cat is more than just a reflection of its wild counterpart. Its behaviours follow closely that of their wild relatives and every cat owner will testify to the wild side of their ‘carpet tiger’. Domestication has not diminished their hunting instincts and a mouse is a mouse, no matter how much food is lavished in the bowl. Cats are predators and remain so even when resting on the settee, or stretching in relaxed ecstasy at the end of the bed. If you own a cat you own a predator and enjoyable though his company may be, he is a killer and will not be reformed. 

Leyhausen, P. (1979) Cat behavior: The predatory and social behavior of domestic and wild cats. New York: Garland STPM press.

Turner, A. and Anton, M. (1997) The big cats and their fossil relatives. Columbia University Press, New York.