Why, evolutionarily speaking, did humans develope self destructive tendencies, like self-harm and suicide? Are there non-human animals that do that?
OK, this one is indeed very hardâŚIâm going to do my best.
There are non-human animals that exhibit self destructive behavior, though whether they intentionally kill themselves is a current matter of debate. The act of suicide as we understand it requires that the individual knows that there are states of life and death that one can transfer between. This level of consciousness is very difficult to measure, so while many animals have been observed engaging in destructive behaviors (like not eating, or holding their heads below water) until they die, itâs currently impossible to know what theyâre thinking.
As for why humans would possibly evolve a trait that could result in one intentionally ending ones own life, that is indeed a very hard one. But the main thing to remember about all human traits is they donât necessarily have anything to do with biological success. Humans are biological, certainly, but we are also hugely cultural. The secret of our success is in working together with other humans and in the transferral of information between individuals and from generation to generation.
In developing this cultural machinery (which is extremely complicated and awesome) the biological machinery can get confounded. What was once a very simple message (make babies, donât die) becomes more complex. Many of the ways that complexity manifests are beautiful and wonderful. For example, exclusively homosexual individuals cannot be selected for biologically, since they do not produce offspring. But having individuals in a society that are socially fulfilled but not producing offspring is culturally advantageous and so makes it more likely that all individuals in the society survive.
But these complexities can also have awful consequences. We crave meaning beyond feeding ourselvesâŚwe want to add to our society and make the world better for those we love. We want to be wantedâŚwe want to care and be cared about. These are drives that push us toward building better and stronger societies. But the intensity of these feelings is inevitably going to vary from person to person as our evolution fine tunes the best balance between strengthening the culture at the expense of the individual. Sometimes the signals we get from our brains and our cultures for how to live a meaningful life get so messed up and detached from reality that it seems impossible that life will ever be pleasant.Â
In short, some situations mixed with some biologies inside of certain cultures are going to result in deep unhappinessâŚsometimes temporarily, sometimes chronically. This was not biologically selected for. Humans are a very weird species designed to deal with a very wide variety of situations, but the situation we currently find ourselves in is vastly different from the one we evolved in.Â
Luckily, we have developed therapeutic and biochemical techniques to help deal with these situations, and our understanding of how to deal with these difficulties continues to grow.Â
Take care of yourself, and remember, accepting help is brave.Â
