Love in the Time of Cannibalism: The Coolest Breakthroughs in the Science of Romance


Orthodera novaezealandiae Some see in love the ultimate reason for human existence; others see only potential for irrational infatuation. Some insist that love is only applicable to a complex species, while others argue that even inanimate objects can love. Recently, papers produced by researchers around the world have portrayed unconventional scenarios of love. We take a look at two articles that illustrate the sometimes fatal, sometimes manipulable characteristics of love.

  1. Love and Sexual Cannibalism

    Think of affection, and cannibalizing your mate may not be the first thing that comes to mind. Yet for the unlucky males of the Orthodera novaezealandiae species of preying mantis, death is the likely outcome of attraction. The displacement of O. novaezealandiae by a sexually cannibalistic invasive species of praying mantis from South Africa – the Miomantis caffra – is becoming apparent. But until now, the mechanisms of this displacement were not well known. Murray P. Fea and his colleagues at the University of Auckland proposed in their 2013 study “Fatal attraction: sexually cannibalistic invaders attract naïve native mantids” that native O. novaezealandiae males are more attracted to the pheromones released by the sexually cannibalistic M. caffra females than to the pheromones released by females of their own species. And in their attempt to approach the M. caffra females, 68% of the O. novaezealandiae males are killed and eaten.

    The draw of O. novaezealandiae males to M. caffra females was demonstrated in the laboratory, where O. novaezealandiae males were placed in tubes leading to two chambers with either O. novaezealandiae females or M. caffra females. On average, O. novaezealandiae males moved toward the chamber containing a M. caffra female more often than they moved toward the chamber containing a female of their own species. Though the male motivation was to copulate, the M. caffra females were more interested in the nutritional value of their male suitors, leading researchers to conclude that sexual cannibalism of the seductive M. caffra females could, indeed, account for the dwindling size of the O. novaezealandiae

  2. Love Potions – In Reverse?

    Unrequited infatuation can be a cause of serious heartache. Luckily, researchers at the University of Oxford led by Brian D. Earp think it might soon be possible to “cure” humans of some of their sensations of love. The idea is referred to as “anti-love biotechnology,” and researchers say the concept can be used to treat cases of problematic personal attachments. Using lust, attraction, and attachment as the three “emotion-motivation subsystems” that characterize human love, the Oxford researchers evaluated how these three emotional drives could be weakened in a 2013 paper called, “If I Could Just Stop Loving You: Anti-Love Biotechnology and the Ethics of a Chemical Breakup.”  Using the current literature of neuroscience as their guide, they found that the same mechanisms used to treat various neural disorders could also potentially “treat” unwanted love.

    To be smitten by every nook and cranny of our universe is to embrace the human love of discovery.

    Broadly speaking, since anti-depressants, particularly those of a class called Selective Serotonin Reuptake Inhibitors, inadvertently regulate testosterone, they also tend to have libido-reducing effects. They can thus provide patients with a novel “anti-lust” treatment. On a similar scale, the obsessive thoughts that characterize early-stage romance can be limited by medicines that target the same neural mechanisms involved in obsessive-compulsive disorder (OCD). Therefore, the same drugs used to treat OCD may potentially be able to dampen the possibility of attraction between individuals, thus providing users with an “anti-attraction” intervention.

    The last of the three subsystems – attachment – is more difficult. Researchers agree that existing technologies can do very little to sever the bond between two individuals, making “anti-attachment” cures a thing of the future. However, studies done in mammals with similar mating habits have shown that the hormones oxytocin, vasopressin and dopamine play a role in bonding. Changes in the level of any one of these hormones change bonding habits; elevated levels facilitated bonding, whereas decreased levels inhibit bonding even after mating multiple times with the same partner.

    Though these mechanisms seem to imply the ability to alter one’s lust, attraction and attachment to another, it’s an ethically messy idea. The use of drugs to lessen the complex interplay of emotions that follow a break-up could arguably interfere with a normal, healthy process of personal growth and self-care. These ethical problems suggest that were such cures finalized, they would be targeted at those with a seriously debilitating, clinically diagnosed case of lovesickness.

The complexities of love and its mechanisms are elusive, and deeply captivating. The frequency with which we allude to love when studying the natural world is a testament to the powerful role it plays in the human experience. To be smitten by every nook and cranny of our universe is to embrace the human love of discovery. And that experience may just be beyond the limits of scientific understanding.

Atrin Toussi is a Brevia guest writer from the University of California, Davis.  She can be reached at