Swinging through the rainforests of South-East Asia, far above the forest floor, at speeds of up to 35 mph, you may find a pair of apes singing a remarkable love song. Their chorus can be heard from great distances, and as their relationship grows stronger their songs become more synchronized and even more beautiful.
These dueting apes are not humans, but gibbons – Hylobatidae, also known as the lesser ape. They roam the tropical rainforests of South-East Asia, and much like humans they form intense pair-bonds with their mate, often lifelong. They are socially monogamous and engage in a variety of behaviors we would associate with attachment. And if something happens to one of the partners, when the other finds a new mate they will not sing the same duet again – that is, they will not sing the same love song to a new partner. I can’t help but think that gibbons are romantic.
Over 90% of bird species will form what biologists call pair-bonds, but less than 3% of mammals do. Humans are unique in so many ways, including our formation of pair-bonds – our drive to find and keep romantic love. In our data from the Single in America Study, we’ve found a variety of interesting things including that single Americans can be extremely romantic. Indeed, like the lifelong bonds of gibbons, 76% of single Americans believe they could stay married to one person forever; and like the flash courtships of many birds, 41% of singles said they believe in love at first sight.
One condition of pair-bonds is often monogamy. While we know that most animals that pair-bond are socially monogamous, having just one partner, we also know that many individuals from monogamous species will engage in sexual infidelity and attempt extra-pair mating. But, mates will encourage their partner’s fidelity (being exclusive), often doing a variety of things to prevent and react to any transgressions. In the Study we found U.S. singles have a similar desire for fidelity. 69% of singles regard fidelity as a “must have”. Being exclusive or faithful is still incredibly important to a vast majority of Americans. To many others fidelity is also important and meaningful, even if not a “must” have. In fact, 70% of people believe that divorce is acceptable after one or both partners cheat. And of those who have experienced infidelity, 78% of people have broken up with their partner after the discovery. American’s are looking for commitment; we are driven to find someone to mutually love.
In addition to research and teaching on romantic love, I’ve studied the evolutionary biology of romantic attachment, cross-cultural reactions to infidelity, and my colleagues and I have looked at the genetic and hormonal bases of mating behavior. Our biology never excuses our behaviors, but it does provide an understanding of why we do the things we do. In the case of monogamy, exclusivity is often desired for a variety of reasons. Biologically, lack of fidelity could result in a loss of resources, increase in disease, and can have a negative impact on our fitness. Psychosocially, we often want to know that we are enough for our romantic partners; that we can provide each other with what we cherish, and trust that we can be fulfilling for each other. Trust is important for human romance – and an expectation of fidelity is still the norm in America. Americans value notions of monogamy. This is not too surprising – after all, the desire for romantic love is not only part of our culture, it is in our biology.
About Justin R. Garcia
Justin R. Garcia is an evolutionary biologist and a SUNY Doctoral Fellow in the Laboratory of Evolutionary Anthropology and Health, Departments of Biological Sciences and Anthropology at Binghamton University in New York. He also holds an appointment as Adjunct Lecturer in the Department of Health & Wellness Studies and is affiliated with the Institute for Evolutionary Studies (EvoS) at Binghamton University.
For more information on our “Single in America” study:
- “Everything You Think You Know About Singles is Wrong” by Match.com
- “The Forgotten Sex: Men” by Dr. Helen Fisher
- “Aren’t You Glad You Weren’t Single Fifty Years Ago?” by Professor Stephanie Coontz
- “Can Love Last?” by Dr. Bianca Acevedo
- “What does the Match.com 2011 Survey tell us about Singles and Money?” by Dr. Jonathan Rich