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Mary was just visiting. That meant there was a new animal in the house. For a week she was joining two other small creatures, a 12-month-old baby girl, and a 3-year-old black and white dog, Kevin, a healthy cattle dog and collie cross. The three of them, the baby and the two dogs, got on well enough, although the dogs were a little nervous of the child. The movement of babies can be unpredictable.
Then the original dog, Kevin, the black one that lived permanently in the house, began to do something he’d never done before. I spotted him pick up one of the baby’s toys, a light brown bunny, and begin to chew gently at the stuffed animal. He’d occasionally toss it in the air.
Kevin was doing something that he’d long ago given up. That was the really odd aspect of the dog’s behaviour. He’d abandoned playing with his own toys round the time he’d turned one (although he still had a good collection of them available). Since then he’s preferred walks, chasing magpies, and squirrels.
Why the sudden change? Maybe the answer was the visiting dog. Did Kevin think the guest was a rival for the attention of the baby? Till now he’d seen the baby mainly as an alarming and unpredictable housemate. He hadn’t shown a proprietorial attitude. But now, perhaps he figured, someone else maybe might want to nudge in.
Jealousy? Kevin’s actions fit the model. Jealousy occurs in competitive triangular situations. One individual may be forced to or think they’re being pressed to give up someone, or something, to another creature. In these situations feelings run high and it’s the loser who displays most agitation. If you stick to phenotypical diagnosis, then it matters little whether the situation involves animals or humans. You need not address the question of whether animals can feel jealousy just as can humans. We don’t really care about feelings, only what you can see happening.
Kevin was jealous of the new dog. His agitation was the product of a disturbance that Mary created in his unpredictable, but stable relationship with the baby. That’s why he unexpectedly took to chewing the baby’s bunny. He was signaling a danger to his exclusive relationship with the baby through a display of benign jealousy - the toy was never harmed. Nor was the visiting dog.
I’d like to be able to say that, once the visiting dog left, Kevin lost his sudden interest in the toy. But he didn’t. The jealousy, presumably, was now between the dog, the baby, and the parents. What this may show - I mean the continued interest in the baby’s toys – is that jealousy is a learned experience. It’s as if, once you’ve been provoked to experience it, a new situation can set off the emotion again. This is a "kindling effect," or a "kindling-sensitization” situation.
Is jealousy a character flaw in Kevin? It’s usual to think that jealousy in any animal or human is a failing. But there was some recent and intriguing information published on jealousy and envy and, by implication, their moral status. This happened during the very same week that Kevin was chewing the bunny. That week the Spanish psychologist Julia Poncela-Casasnovas and her colleagues put out a paper on envy (and, it follows, on jealousy). It was entitled “Humans display a reduced set of consistent behavioral phenotypes in dyadic games” (Sci. Adv. 2, e1600451 (2016)).
But envy? I don’t think there is much to be gained by distinguishing too carefully between jealousy and envy. Envy’s said to relate to what you’d like to get, jealousy to what you fear losing. Feelings of loss or of gain can’t easily be proved. But the competitive triangle and the agitation it brings can be and they’re common to both. Does Poncela-Casasnovas help to understand Kevin? Let’s see.
Dr. Julia Poncela-Casasnovas’ experiment used a variety of games to determine whether players would do the logical thing and cooperate to compete to gain a greater reward. Or, she wondered, would they act selfishly and compete on their own to aim to win a smaller but guaranteed payout. One of the five games she and her team adopted to test the question of cooperation is called Stag Hunt. The game’s said to mirror social cooperation – or its envious absence. Poncela-Casasnovas hoped that she could, using this game and others, show what percentage of her 541 research subjects would wager on cooperation to gain a bigger reward, and how many would go it alone for the secure, but uncooperative smaller share.
In this version of the Stag Hunt two people go out on a hunt. They can hunt for a stag or for a rabbit (like Kevin). Each player in this game settles on course of action without knowing the choice of the other person. To get the stag the two players have to cooperate. But a person, on their own, can go for the bunny, which is worth much less than the stag, In Julia Poncela-Casasnova’s version the reward was raffle tickets offering a chance to win big. Stags were more valuable, but getting them was more difficult and required cooperation. Not so for the lower value bunnies. 30% of contestants seem to have gone for the easier shot.
Why did such a large number of individuals choose rabbits [even] “when they are at risk of being left with lower payoff than their counterpart?” Poncela-Casasnovas and her colleagues conclude that many individuals were not keen on the prospect “of another person doing better than them, even if it meant they received less”.
Because Poncela-Casasnovas’ team found so many subjects willing to go for bunnies they subjected player reactions to computer analysis. They claim they were able to cluster the responses according to four strategies: “envious, optimist, pessimist, trustful, and a small group of individuals referred to as undefined, who play an unknown strategy.” Poncela-Casasnovas believes that the results derived from her 541 research subjects can be extrapolated to the populations in which we all live. Nearly “ninety per cent of the population can be divided into [the] four basic temperaments. Of these `envious’ personalities are the most widespread – with nearly one in three people falling into the category.”
Kevin can come back now. The specifics of the envy experiment are not what count for understanding Kevin’s behavior. But Poncela-Casasnovas’ conclusion, that the envious or jealous individual represents a standard character type that’s 30% common, is. Kevin’s behaving like that 30%. It’d be as wrong to look down on his feelings just as it would be to look down on someone who’s an optimist or trustful. If Julia Poncela-Casasnovas is correct, it makes envy and jealousy emotions that can be understood as normal features of the human character - and if phenotypes mean anything - of the animal. What Kevin was experiencing and learning was perfectly conventional.
