Friday, February 22, 2013

The Cat’s Meow

 -A human introduction to feline behavior by Matteo A. Vaiente


During many of my long, treacherous nights in graduate school while oscillating between hopelessness and despair, my feline companion Fig offered to me much needed companionship. During the darkest hours of these long nights, I began to take notice of his behavior and wondered what exactly he was thinking or trying to tell me he would meow, purr, or, most often, forcefully butt me with his head…Fascinated by the idea that Fig was perhaps trying to communicate to me, I decided to do a little research and to share with interested readers, cat-lovers, and biologists some of the current scientific research that is attempting to characterize some peculiar cat behaviors.

Interestingly cats, or for scientific purposes the family Felidae, are typically asocial creatures with domesticated cats being one of the few gregarious exceptions along with tigers, lions and a few others. However solitary, there is still a biological imperative for these organisms to communicate and procreate. One of the ways that cats communicate is through olfactory marking, a behavior that has been well established. Common methods of marking include using feces and urine (an effluvium which some cat owners may have had the pleasure of dealing with, as I have).One of the most lovable, albeit striking, things about Fig is that he LOVES to head butt and rub his cheeks on nearly everything, and everyone. This behavior is thought to act in the same was as other olfactory marking mechanisms in felines, as a way to leave behind and detect scents from other individuals in the population. 

Researchers have recently discovered that large wild cats respond positively to cardboard that has been rubbed on the forehead or cheek of another individual within the same species and were interested in characterizing the chemical scents left behind after head and cheek rubbing behaviors. Of the many volatile chemicals they found, tigers showed the highest proportion of a chemical 2-pentadecanone compared to other species. Also, medium chain linear carboxylic acids were found in higher proportions in tigers and lions compared to cougars and leopards1.

These results are exciting because they suggest that the array of chemicals released from the faces of felines display potential functions for communication, potentially even with each species evolving its own unique scent based language, as species specific mixtures appear to exist. From the study on wild cats, 100 chemicals with matches to previously published spectrum were identified using gas chromatography-mass spectrometry (GC-MS) approach (for the non-technical crowd, that’s just a sophisticated way to separate and weigh a mixture of things on a chemical level.) and even some novel compounds1.  While this research is brand new, it offers an interesting opportunity to understand how animals can use complex olfactory signals to communicate with one another in a coordinated way.

As many cat owners (or any pet owner, really) will attest to, each and every pet seems to have its own personality. I certainly believe that my little fig has a quite distinct personality, which I believe distinguishes his from other cats. He is extremely gregarious, and has no problem approaching strangers, offering them affection and unlike any cat I have seen. Whether this is an artifactual association used to reconcile the intense feelings of companionship and love that pet owners have toward their furry little friends or truly individual variation in behavioral patterns due to either nature or nurture has recently been examined by animal behaviorists2.

In this study, kittens from 9 different litters were examined born of 9 different mothers were examined. The cats were followed for a period of 2 years, and were observed for 5 minutes after feeding at ages 4, 12, and 24 months. During this time, behavioral patterns were observed and were grouped into categories. These categories included:  staying inside, rubbing and investigative.  Of particular interest, rubbing behaviors increased with age in all litters, but were distinctly clustered within litters; or kittens in the same litter were more likely to have similar frequencies of rubbing behaviors. This is suggested to function as a way for cats to receive tactile stimulation and to communicate with others and their owners in a tactile way, and interestingly these behaviors were the most common among kittens with the least amount of human handling at < 3 months of age, indicating this may be a mechanism to elicit more human contact during infancy2.

I did not know much about fig’s life before I luckily met him my first weekend after beginning graduate school, but his behavior seems to suggest that he and his littermates were predisposed (perhaps genetically, as speculated within the study) to tactile stimulation and that he was not handled by humans often during his formative years.  When examined with the experimental results above, there may be implications in also recognizing litter mates, as they may be more likely to have similar chemical compositions of secretions for their scent glands. While rubbing behavior has also been described and linked to detect olfactory secretions from other members of Felidae. These results are exciting since they seem to suggest that individual cats have distinct behaviors, and the frequency of a cat’s behaviors may be influenced not only be genetic factors but also by how they were nurtured and socialized as kittens.

Further corroboration that the chemicals released from the facial area of cats are used in informing cat behavioral traits associated with marking behavior (in this case urine) was presented in 2010 by Pachel in the Journal of American Veterinary Association3. A case study was presented of an otherwise normal male cat that began episodic urination on surfaces in its home in response to some undefined stimulus. A therapeutic treatment using a synthetic feline facial pheromone was effective in reducing the inappropriate behavior3,4.

As far as Fig goes, sometimes he is not always lovingly spreading his cornucopia of chemicals on the tables, chairs, books and backpacks that clutter my 1930’s built apartment; and he has become quite used to being handled and consistently demands this attention with a cacophony of howls and meows that he often accompanies nightfall. But during those dark hours of the night, when I’m still awake from his incessant pestering, I’m glad he’s at least remembering not to pee on me.

1.            Soini, H. A. et al. Investigation of Scents on Cheeks and Foreheads of Large Felines in Connection to the Facial Marking Behavior. J Chem Ecol 38, 145–156 (2012).
2.            Lowe, S. E. & Bradshaw, J. W. S. Ontogeny of individuality in the domestic cat in the home environment. Anim Behav 61, 231–237 (2001).
3.            Pachel, C. L. Animal Behavior Case of the Month. Journal of the American Veterinary Medical Association 239, 1433–1434 (2011).
4.            Griffith, C. A., Steigerwald, E. S. & Buffington, C. A. Effects of a synthetic facial pheromone on behavior of cats. J. Am. Vet. Med. Assoc. 217, 1154–1156 (2000).

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