How Deep Is Our Love?

Compassion plays a key role in human evolution.

With the recent spate of school shootings, terrorist beheadings, and presidential candidates arguing for increased xenophobia and a naturalness for sexual violence, the world does not feel like a very compassionate place. But it is. Or better put, we are.

The emergence and frequency of terrorism, warfare, and belligerence is not a sign that humans, as a species, are becoming less compassionate. Sure, we are capable of horrendous cruelty, as evidenced by any glance at the daily news. Nevertheless, day after day humans across the planet commit far more acts of compassion than cruelty. Our capacity for compassion is a key part of human evolution, past, present and future. 

Think about the complexities in forming and maintaining the kinds of communities our ancestors did over the last million years—there would have been many, many times when individuals would have fallen ill, been injured, or even just gotten old and lost some of their physical capacity. When this happens in most other animals, the injured or ill member of the group usually gets isolated, sometimes even attacked, and slowly moves off and disappears. One of the amazing transitions in our lineage over the last million years was the emergence of behaviors that kept the injured, sick and aged alive and part of the community. Very early on our ancestors expanded the hormone-behavior system involved in the mother-infant bond and spread it to a broader care capacity (see here and here). This ability to care for our children was expanded even further and manifested itself as an ability to care for others unrivaled in any other species.

Starting as far back as 1.8 million years ago we see evidence of the acquisition and sharing of meat from scavenged prey, from rich roots and other important food sources. We see the advent of care of the group’s children by both males and females, young and old. Both of these aspects, the substantive sharing of food and the widespread caretaking across the group assisted our ancestors in being successful, but they took that even a few steps further. Work by the archeologist Penny Spikins and colleagues offers nice insight into this history by looking at the human fossil record and the evidence of compassion.

At the 1.8 million years old site of Dmanisi in Georgia, one of the adult individuals there had lost all but one tooth many years before he died (we know this as all of the sockets except for the canine teeth were re-absorbed in the jawbone). This means others in the group had to have provided digestible food for him… they may have even pre-chewed it. Another example comes from a site 1.5 million years ago in Kenya where the remains of a female Homo erectus show evidence that she was likely suffering from hypervitaminosis A, a disease caused by too much vitamin A in the diet. This disorder can cause problems with bone density and can damage bone growth, the evidence of which are seen in the fossils. If she had the disease it would have taken weeks, even months to develop, causing her to experience nausea, headaches, stomach aches, dizziness, blurred vision, and reduced muscle capacity, and fainting. These would have seriously limited her ability to contribute to the group or even fend for herself, but she survived. We know this as it takes quite a long time for this disease to manifest in the bones, and her fossil shows that she bore the brunt of it. She was cared for extensively.

At another site called Sima de los Huesos in Spain, about 530,000 years ago, there is evidence of a child (maybe ~8 years old) with a birth defect called “lambdoid single suture craniosynostosis” where the bones of the skull fuse very early and cause serious problems with brain growth leading to mental retardation, locomotor challenges, and disfigurement of the face and head. This child lived at least 5 years or more with this syndrome, looking and acting very different from others and needing a lot of assistance and care…which he got.

These three examples might not seem like much, but when you think about the entire catalogue of fossils that we have from of these ages (there are not that many) you see that the fact that we found even these few suggests that compassion was already widespread and contributed to the development of the evolving human community during this early period. This means that over a substantial part of the history of our lineage, compassion gradually became extended widely across communities and was displayed in extensive investments in caring for offspring, for ill individuals, and for each other with regularity and increased efficiency. 

More recently, we have moved this capacity for compassion beyond our communities, beyond even species boundaries and extended it to strangers, animals, objects, and even abstract concepts (like “God” or “Nation,” for example). Humans really know how to care about others. But before we get overly warm and fuzzy about our capacity for compassion, we have to remember that there is a flip side to intensively cooperative and compassionate communities. Sometimes the tighter you bind within your own community the more weary you are of other communities. For most of our history population densities were very low, so groups were few and far between. When they did encounter one another it was more often than not beneficial to spend some time together, to collaborate and even exchange members. These early communities were small enough that it was not the case that too little food or not enough space caused stress. And the mixing of members was probably both socially and biologically healthy. But as human communities grew in size groups coalesced together developing stronger senses of identity. Association with specific places due to agriculture, storage, and other deep investments in land acted to enhance the feelings of “us” and “them” and the flip side of compassion—cruelty and conflict—became a bit more common.

Which brings us to today…

It is true that violent and cruel events happen, but these events reflect a minority of the interactions between people? There is a major bias in news coverage and we seldom hear about the daily acts of compassion and caring that characterize humanity. Humans need one another in the past, the present and the future. That is not going to change. We have an amazing capacity for compassion, we should remember to use it, and to notice it, as often as we can.

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