Awareness of the individual self has long been a philosophical and psychological problem we have trouble fully understanding. Much of our ideas already assume that we are aware of ourselves as individuals, and then explore how our self identities shape other areas of our lives. But how do we even know what our “self” consists of?

Today, I will dive into a biological perspective of the self. What allows complex organisms to maintain a sense of self? Does one require intelligence to have a sense of self? And how can this concept be applied to larger systems, like communities or species? By exploring the concept of self from a biological point of view, we may come to a deeper understanding of what the self truly is.

The Biological Basis of Self

To start off, we will define the self for an organism. Biologically, each and every organism has a concept of the self that is based on life necessities. Ultimately, a sense of self comes from the overall desire for an organism to live, survive, and reproduce. These biological bases for life ultimately provide us a sense of individuality and self — we live and fight for our own survival.

Compare this to the parts that make up a multicellular organism. For example, consider a single skin cell in a human. We already know the organism, a human, has a sense of self. Does the skin cell also have a sense of self? Or does the human’s sense of self take precedence?

Skin is a unique, very replaceable organ. The first 18 to 23 layers of our epidermis — the outermost layer of skin — is made up of dead skin cells. Our body sheds almost 40,000 skin cells a day, and forms more cells every day to replace those that were lost. A single skin cell here does not prioritize its own survival at all. Rather, it is merely a tool to benefit and protect the overall human and keep them alive. By the previous definition, a single cell in a multicellular organism does not have a sense of self.

But exactly how do multicellular organisms maintain an overall sense of self? Or rather, how do individual cells lose their sense f self to a greater collective?

One aspect of cell biology that may explain this are gap junctions, which are channels between cells to share information between them. Gap junctions basically allow cells to share the chemical signaling that happens within it to nearby cells, which helps tissues and organs act as single units. Just like how our brain hemispheres act as one unit due to the corpus callosum connecting them, gap junctions meld cells together in a way that a cell doesn’t know where it ends and where another cell begins. To connected cells, gap junctions make it so that signaling pathways or reactions in Cell A may as well have occurred in Cell B since both experience the process and its effects. Because the cells’ memory is merged, cells are unable to tell what happened to itself versus what happened to its neighbors, which ends up creating a compound sense of self.

An Example In Cancer

Because gap junctions play such a key role in diffusing a cell’s sense of self into tissues, to organs, to the overall organism, it follows that the closing of gap junctions revives a cell’s individual sense of self.

One of the first steps in cancer progression is the closure of gap junctions. Once gap junctions close, a cell reverts back to a unicellular self and acts like an independent organism from the rest of the body. As such, the cell prioritizes its own survival and reproduction, and considers the body as its environment.

Cancer cells act remarkably similarly to bacteria. They divide very quickly, drain the resources in their vicinity, and metastasize to better locations for growth. Like an infection, their primary motive is to feed off of the body they are in and reproduce as much as possible. If we consider cancer a disease of a shrinking sense of self, one way of treating cancer effectively may include reopening gap junctions and helping cells rejoin the body. By doing this, we could revert cells back to the organism-level sense of self.

Self-Sacrifice

Tenets of this biological basis of self can be easily applied to other contexts, such as the social sphere.

One intriguing animal behavior, known as altruism, might be explained by this sense of self. Altruism is a behavior that sacrifices the individual for the greater community. For example, when it senses a nearby predator, a meerkat on watch may call out to signal others in their community to evacuate the area despite the action calling the predator’s attention to itself. Ultimately, the meerkat is sacrificing its own life for the lives of its family.

The simplest biological explanation for this behavior is that by protecting members of its immediate family, the meerkat increases the likelihood of its genes being passed on through the offspring of its family despite losing the possibility of having its own offspring. When compared to the biological sense of self, the meerkat acts like a single cell as part of a greater collective — ready to lay down its life for the benefit of the family.

The Community Organism

The way communities shape human values and experiences could also be compared to the biological sense of self. Like cells who share an identity by sharing chemistry and signals between them, humans are significantly shaped by the communities they grow up in, where they are constantly surrounded and influenced by other people’s beliefs, values, and actions. Family, neighborhoods, cultural groups, and religion all tweak and solidify the core values and beliefs you hold when you are older.

On a darker note, groups such as cults or extremist organizations also take advantage of the power of community to brainwash and build a group of loyal followers. These organizations reach out to the most susceptible — people who are already isolated from a social support system or feel like they are not accepted by others (similar to cells that have their gap junctions closed).

Organizations like QAnon feed fear, qualify intolerant views, and provide a sense of acceptance, promising community and protection in exchange for loyalty to their cause. Supporters or members of these groups end up so loyal and trusting of these organizations that they begin to distrust factual data and researched information from the government, media, or even science. Anybody who is not a part of their group is an “outsider,” not to be trusted or even respected.

Humans can even lose their own sense of self to a community. For example, suicide bombers in ISIS lose so much of their individual sense of self for the cause that their community believes in that they have no qualms dying for their ideologies. Just like a skin cell dying and being replaced in a human body, they readily accept that they must die and will probably be replaced for the success of their organization.

The biological basis of self is incredibly applicable to many contexts and concepts of self, from cell biology to communities. Some of these comparisons are not perfect, of course — human societies are not hive-minds, and we don’t share every single experience with one another. However, it is interesting to see how the idea of a self melts and intersects with communities and family units. By exploring the idea of self through many contexts, we may come to new understandings of the world around us, and perhaps make breakthrough discoveries or ways of thinking about our world.

Hi, I'm Ash. I’m a college sophomore and aspiring scientist who loves discussing science, the brain, and our ever-changing society.