Jealousy might be considered one of the biggest enemies of a happy, healthy relationship. Envy and romantic suspicions are often tipped as the classic sources of discord in an otherwise pleasant partnership.
But according to new research from the University of California, our preconceptions of jealousy may be dead wrong – in fact, it could even play a part in keeping couples together.
Researchers scanned the brains and measured the hormone levels of eight male titi monkeys after getting them jealous (by showing the poor things their girlfriends playing with another male). These monkeys mate for life, like we do. The scientists also observed the monkey's body language.
They then compared the results with monkeys who didn’t have a relationship to the female they saw, so weren’t experiencing 'jealousy,' as we know it.
The jealous monkeys reportedly displayed more activity in the cingulate cortex of the brain, which is associated with social pain in humans, and in the lateral septum, which plays a role in emotional processes and stress responses.
The paper, published in the journal Frontiers in Ecology and Evolution, explained that the lateral septum has been linked to the formation of pair bonds in primates.
The titi monkeys also experienced a spike in testosterone and cortisol hormone levels.
The researchers explain that jealousy may strengthen the bond we build with our partner, and that behaviours such as keeping them away from strangers and warning off competition is all part of evolution’s way of keeping couples together.
The study states:
These neural and physiological changes may underpin the emotion of jealousy, which can act in a monogamous species to preserve the long-term integrity of the pair.
They concluded that their findings were relevant to humans.