Humans have a tendency to form long-term pair bonds. This refers to entering socially monogamous sexual or romantic relationships for a certain period of time. The most common example of this in human society is marriage. These pair bonds are not lifelong and instead humans can form several pair bonds in a single lifetime. Pair bonds have several evolutionary benefits that have been widely covered. However, what is less extensively covered is the evolutionary cost of a pair bond disintegrating, or rather the evolutionary costs of heartbreak.
The most common consequence of a pair bond dissolving is the impact it has on child-rearing. There is strong evidence to suggest that successful pair bonds predict better health for both the off-spring and the adults. Pair bonds also guarantee that the father will make investments in their offspring to ensure their survival. In hunter-gatherer societies, pair bonds ascertained that a part of the male’s hunt would be for the offspring in order to meet its high nutritional requirement, and the rest would be matched by the mother’s gathering and foraging attempts. In today’s society, paternal investment may come in the form of various other resources- including monetary resources, housing or even physical protection. Literature suggests that women are more likely to opt for abortion when there is lower support for child-rearing, referring to both bi-parental and alloparenting care. This is because the cost of child-rearing significantly increases for a single parent in a manner that they may not be able to match.
These findings are also supported by investigations on the evolutionary benefits of religion. It was found that church-goers had better rates of maternal fertility and child outcomes, likely due to the social network, support, and cooperation the church yields.
According to an article published in the journal Nature Human Behaviour journal “Human beings are a social species that rely on cooperation to survive and thrive.” However, it is not always easy to identify a cooperator who will engage in an equal trade-off, without engaging in forms of cheating or social loafing. Recognizing a cooperator before every interaction may be cognitively difficult and costly. A simpler strategy may be to engage repeatedly with a previously identified cooperator. This has given rise to monogamous relationships in human society. A break up then implies that one loses a cooperator along with the resources they provided. At least, temporarily then, one’s effectiveness at navigating through society is diminished. This is, however, not to say that mates are the only form of cooperators- parents, siblings, other members of kin and friends can also provide resources. Yet, the loss of mate is often associated with a loss of resources that then needs to be replaced via alternate sources or a new mate, which in itself can have several costs linked to cognitive effort and searching. The availability of a new mate is also based on the spatial and temporal distribution of the gender(s) that one is attracted to. A random spatial distribution over a uniform one makes it harder to find a supplementary mate. Very simply, if there is an equal ratio of men and women in an area, then it would be easier for a heterosexual individual to find a new partner. However, taking the example of Haryana that reportedly had only 831 women for every 1000 men between the years of 2013 and 2015, it would be harder for heterosexual men to find a new partner very easily. Hence, they would have to devote more time and effort towards acquiring a new mate, which can be costly.
A break up can also do significant damage to one’s signaling abilities. According to signaling theory, all behaviours we engage in have two ultimate motives: status signaling and sexual signaling. These forms of signaling are aimed to enhance one’s chances of survival or survival of their genes and kin. Status signaling refers to showing off one’s resources or access to resources. Often those with a higher social status tend to survive better. The pandemic exemplifies this perfectly, where those who are wealthier have found greater access to healthcare than those who lead a relatively frugal lifestyle. Sexual signaling refers to boasting certain features or characteristics that are likely to attract a potential mate. The peacock’s tail is an excellent example of sexual signaling. While the tail is an expensive adaptation, i.e., it is likely to get the peacock with a more colourful tail hunted down, it also shows the peacock’s potential mate it’s ability to acquire nutrition and survive despite being conspicuous.
During a break-up, there is often a rejector and a rejectee, both of whom face different consequences to their abilities to signal. For the rejector, the damage often occurs to their status signaling. Rejectors often suffer from consequences to their reputation as being unsympathetic, or ‘heartless,’ which may not only damage their ability to obtain future long-term mates, but may also impact how they are perceived amongst a shared group of friends with their rejectee. Rejectees on the other hand, often lose their ability to sexual signal as efficiently. Being rejected often decreases one’s mate value. Moreover, it is often linked to negative affect, rumination and a decrease in self-confidence. This also reduces their self efficacy and self esteem with regard to posturing and attracting a new mate.
Overall, breakups are likely to involve a cost as they involve investment: higher the investment, higher the cost. As per the arguments presented above, a divorce between partners with children is likely to be the costliest, with impact not only on the two partners separating, but also on their offspring. However, evolutionary costs are not exclusive to parties that are subject to the divorce. Ending of all pair bonds, whether short-term or long-term, are likely to present a few ultimate consequences to the resource availability and signaling strength of both members in the dyad.
Feryl Badiani
