The Importance Of Friends For Non-Human Animals’ Health
Having a rich and full social life can be helpful for people in numerous ways. Researchers have long studied how our social lives affect our health, and many studies have made a link between social difficulties and poor health, both physical and mental. Noteworthy, here, is the underlying nuance: above and beyond good friends and a vibrant social life promoting health and longevity, our social environments literally reshape and reform our long-term health trajectories, but also the very essence of good health with respect to cellular functioning in our day-to-day lives. Certainly, advocates of animal welfare will be familiar with the hardships and suffering endured by non-human animals at the hands of our own species. Yet, until recently, fairly little work was able to show if and how these same social mechanisms that impact human health extended to our non-human cohabitants.
This paper, by a team of scientists across several universities, extends this work to non-human animals in novel and profound ways. Drawing on previous research, they first show that average life expectancy can differ by a full twenty years for people who experience six major “adverse childhood experiences” compared those who experience none. Similarly, those who deal with difficult upbringings have less vibrant social lives, fewer economic resources, and also have higher rates of asthma, diabetes, cancer, and bronchitis amongst other issues. It’s a notion that is well-documented in public health literature for humans, and is well-substantiated.
In this study, researchers explored how important “social determinants” are for predicting risk of death and general well-being for animals. In it, a team biologists and health experts applied the idea of “social determinants of health” to non-human animals, demonstrating clearly the rich social needs of a variety of animals, and showing in the process that their social needs must be taken seriously. Specifically, they find “that measures of social integration, social support, and, to a lesser extent, social status independently predict lifespan in at least four different mammalian orders,” including several species of monkeys, Orca whales and dolphins, and even Bighorn Sheep, Meerkats, and rabbits.
This variety of non-human social mammals benefits tremendously from better social conditions. For example, amongst Orcas, stronger social bonds protect against early mortality, while in Bighorn Sheep, more time spent with one’s kin group and friends predicts a higher tolerance to stress and its associated health risks. More generally, across all of these animals, those with more equal social networks, closer friendships, and who face less social hardship live longer and with fewer health complications. These differences can even be seen as far down as the molecular level—their bodies have lower levels of stress hormones such as cortisol and they show fewer signs of age-related wear and tear and disease, namely inflammation and levels of “senescent cells,” or dead tissue occupying space in otherwise healthy parts of their bodies.
Of further interest for animal welfare supporters, previous work in humans has shown that the physiological effects of isolation can be felt in subsequent generations. This paper extends the same logic to our non-human counterparts, illustrating ever more clearly the need for reform and protection of animal welfare now in protection of future generations. As this pertains to one of the more famous mantras adapted from evolutionary biology (i.e. “Survival of the fittest,”), scientists traditionally think of fitness as an organism’s ability to live fruitfully enough to pass its genes on to the next of kin. The rich social environments, then, that protect the previously mentioned variety of animals from poor health also serve to increase each individual’s fitness. This is a subtle point but should not be understated: the physical capacity of non-human animals to live well and produce similarly healthy, vivacious future generations is as intricately dependent on their having well-connected, joyous social lives as in humans. As an illustration, one of the more intriguing findings of this current paper was that wild mammals with mixed-age social groups (i.e. they grew up with and surrounded by siblings, older mentors, and younger peers too) lived longer and healthier still than those who grew up in relative isolation. The similarities to humans are staggering and should give us pause in reassessing our moral consideration of these complex creatures.
As mentioned above, while the impact of stress in non-human animals such as Bighorn Sheep and Orcas is intergenerational, negative experiences in their early childhoods is just as if not more detrimental for their long-term health. We see the same phenomenon in humans; for example, people who grow up in poverty have much higher rates of asthma, cancer, and heart disease later on. While these conditions don’t map perfectly onto non-human animals, the general pattern persists. One case the authors draw from is the drastically shortened life expectancies of orphaned Elephants that survive to adulthood. In particular, these elephants live substantially shortened lives relative to their peers even if they “catch up” in terms of social status later on.
Yet another illustration indicates the importance of a healthy social life across the life course. Macaque monkeys who are lower on the social ladder not only die younger but also experience worse health while they’re alive. In males, not only are lower status monkeys more susceptible to viruses, they also have a significantly higher prevalence of heart disease, an otherwise fairly uncommon condition in wild monkeys.
Ultimately, the researchers intend this paper as a unification of biological and health sciences, with a primary emphasis on the implications for humans. The writing, however, is on the wall. While this comes as no surprise to animal rights advocates, the authors make a crucial part of the struggle for improving animal welfare more scientifically clear: our non-human cohabitants of Earth are sensitive, complex, and importantly, aware beings that respond to rich social surroundings much like any of us would. This has to be recognized on a broader scale to bring about the changes necessary to improve the lives of animals everywhere. This is perhaps particularly true given that many of the animals that are “used” every year for food are highly social creatures, such as pigs, cows, and chickens. That they may be massively suffering is something that needs to be addressed on a societal scale and protect them in the ways that they can’t themselves.
https://doi.org/10.1126/science.aax9553