It’s Saturday. This morning after shuffling passed the pile of work on my desk to take groggy refuge on the couch, I decided to do something mildly frivolous. I dropped the search terms “Felis catus” (domestic cat) and “behaviour” into Web Of Science.
My cat, Jasmine, has a sometimes endearing, sometimes frustrating propensity to kitty kisses. It’s endearing when you come home from a long day and she’s so pleased to see you. It’s frustrating when you’re trying to sleep and her sandpaper tongue finds your nose while your eyes are closed and you’ve just started to drift your way into that elusive but beautiful paradise of sleep.
When I say “your” here… I really mean “my”. “My” poor, sleepy, pillow-squished nose or cheek or forehead. Or exposed arm. Or sometimes my duvet if it has the gall to get in the way of her ministrations.
The first relevant article I came across was “Head Rubbing and Licking Reinforce Social Bonds in a Group of Captive African Lions, Panthera leo” by Matoba, Kutsukake, and Hasegawa (2013). While the species isn’t right, this certainly sounds like the right suite of behaviours. I’m willing to cast my net pretty wide to understand Jasmine anyway because she’s a Bengal; a breed of domestic cat that comes from back-crossing hybrids of Asian Leopard Cats with domestic cats. Maybe some of her quirkiness comes from her non F. catus Felidae roots.
Matoba et al. conveniently start by reviewing literature on other felids. Apparently domestic cats use grooming in a lot of ways. Some seem to use it to maintain relationships with their feline housemates (Curtis et al. 2003). However, some seem to use it to establish or maintain dominance structures (van den Bos 1998)! Later they go on to talk about lion behaviours, such as head-butting or rubbing, and licking/grooming, which is typically considered to be both hygienic and social (Schaller 1972, Rudnai 1973), just as it is in other mammalian taxa including primates (Kutsukake and Clutton-Brock 2006, Wilkinson 1986, Schino 2007, 2008).
Matoba et al. had three non-exclusive hypotheses for the social function of grooming and head-butting in lions.
(1) Tension Reduction: like kissing to make up. The idea here is that some of these behaviours strengthen stressed or uncertain relationships, for example, after conflict or separation. If this was the case, they would predict higher frequencies of these behaviours after periods of separation. Since cub-rearing is communal for lions, individuals of similar ages have probably been closely associated for a long time; if tension reduction is at play, they predicted that lions with bigger age differences would share more head-butts and kitty kisses.
(2) Social Bond: The behaviours may be to strengthen or maintain pre-existing social bonds. Female lions spend their whole lives together in one pride, while male lions form groups and leave their parent prides to become nomadic. These nomadic groups of males fight with other prides, and if successful, take over residency (Bertrum 1975). If the social bond hypothesis is correct, the authors predicted that grooming etc would be more common in same-sex pairs, closely related pairs, and similarly aged pairs because these pairs would have spent more time together. This would be in contrast to the predictions of the Tension Reduction Hypothesis. They also predicted that the behaviours should be reciprocal.
(3) Expression of Social Status: The behaviours could be to express dominance to subordinate pride-mates, or vise versa. Lions do not maintain a social structure within each sex (Packer et al. 2001, Schaller 1972), however, because males are larger than females and thus able to win physical contests, Matoba et al. suggested that there may be a dominance hierarchy with males higher than females. If these behaviours are an assertion of dominance, they predicted that they should be more frequent from males to females, or the opposite if it is an expression of submission. This is opposed to the Social Bond Hypothesis that suggested the behaviours would be reciprocal.
To test their hypotheses, the authors collected 101 hours of observational data across 27 days for a captive pride that included 6 adult males, 12 adult females, 1 subadult male, and 2 subadult females (total 21).
Grooming and head butting was not seen more after separation, and was more common if the lions were closer in age – so they found no evidence to support the Tension Reduction Hypothesis.
Female-female grooming was highly correlated with relatedness, and was reciprocal. Head-butting behaviour was also found to be reciprocal, especially between pairs that were closely related. Thus, they found support the Social Bond Hypothesis.
Lastly, their results show mixed support for the Expression of Social Status Hypothesis. They found that males rubbed heads with males significantly more frequently than they did with females, and that females rubbed heads with males more frequently than with other females. This suggests that head-rubbing might be used to express submission, but there was nothing to suggest they used it to express dominance. Grooming was observed almost exclusively between females, so there was no evidence that this behaviour is related to dominance at all.
This is all fascinating stuff, but from reading this paper alone, I don’t feel like I’m any closer to understanding my kitty’s kitty kisses. After all, I’m not a cat, she doesn’t restrict her kisses to other cats or other female cats. Anyone who dares to scoop her up is in serious danger of getting their nose sandpapered.
I suppose if she sees us all as cats, then she could be trying to strengthen our social bonds. It’s not reciprocal (I don’t make a habit of licking her back; I don’t fancy the thought of a hairball), and it does frequently happen when we’ve been separated (me being asleep is a separation, right?), so there could be some evidence for either the Tension Reduction or Expression of Social Status Hypothesis!
… My intuition tells me that she’s using it to demand attention though. “Wake up and cuddle me!”, “You’re home, play with me!”, “Stop blogging and get the itch on my back!”… Actually, this sounds like an expression of dominance. Yes, kitty master, right away, kitty master.
Luckily, Matoba et al. 2013 contained lots of references to other papers to follow as leads. I have plenty to keep me busy during those groggy mornings when I quest to understand the inner workings of Jasmine’s brain; if I discover anything worth sharing, maybe I will!
On my reading list:
- Cameron-Beaumont C, Lowe SE, Bradshaw JW (2002) Evidence suggesting preadaptation to domestication throughout the small Felidae. Biol J Linn Soc 75:361–366.
- Atsuko Saito, Kazutaka Shinozuka (2013) Vocal recognition of owners by domestic cats (Felis catus). Anim Cogn 16:685-690.