Serendip is an independent site partnering with faculty at multiple colleges and universities around the world. Happy exploring!
Remote Ready Biology Learning Activities has 50 remote-ready activities, which work for either your classroom or remote teaching.
purpose of altruism
Just because behavior is based from the brain, doesn't mean that all output from the brain is the result of a simple reward system. It seems to me that you are confusing the evolutionary reasoning for a brain to exist with the purpose it serves for us now, two very different things. There was evolutionary pressure on the brain to grow larger, which gave the brain the capacity it has now for thought and behavior. However, as humans with reasoning capabilities which grew out of this enlarged brain (for whatever reason, there are a few theories) we are able to make moral decisions that go against what biologically may seem reasonable or the most rewarding.
As human beings, we have the ability to make decisions that may not be in the best interest of evolution, we can thwart it. Like an animal-lover who may risk his life for a cat about to be run over, evolutionarily this has no reason to exist. However, it exists out of existing altruistic mechanisms in the brain as well as our ability to act above the cruel wishes of evolution; for if we could not thwart evolution, we wouldn't use condoms, but rather would have sex with the purpose of creating birth every time, because wouldn't that best increase our biological fitness?
That being said, there is a biological reason for altruism to exist. Richard Dawkins introduced the idea of the selfish gene in the 70’s, and his theory is now thought to be the best way to look at evolution. His view was that evolution didn’t work at the level of the organism itself, but rather at the level of genes. We are simply replicators that house genes, and through the process of natural selection, gene pools are changed based on which replicators were able to reproduce more. This idea may seem outrageous, providing an unnecessarily bleak outlook on life and indeed our own purpose, however it accounts for altruism and other behaviors that are otherwise mysteries. According to this theory, organisms that developed altruistic behavior were likely to act that way towards relatives (kin selection), which therefore increased the likelihood that these organisms with shared genes, would prosper. So in fact, this altruistic behavior is not actually altruistic, but selfish from the viewpoint of the genes, since they are in actuality helping themselves move on to the next generation. Now of course, none of this is “planned” or can be “foreseen” by the genes, but works on the principle that the genes that caused their replicators to act this way became more and more prevalent, so this behavior was selected for. This works even in organisms that do not have the ability to think and process as we do, such as bees. This is just the simplest case, and there are many more reasons for it outlined by Richard Dawkins in his book the Selfish Gene, but from this we can see that there is a legitimate mechanism for altruism to exist.
In humans, this whole thing becomes more complicated, and game theory is often used to examine the effects of complicated minds living together. In fact, one of the reasons that has been suggested for why human beings have such a wide range of facial movements and eye recognition of these movements is to detect and recognize people with whom in relationships have been formed in the past, and to remember if they have cooperated in reciprocation or if they have defected.
There are evolutionary and mechanical reasons for altruism to exist. However, humans take morality to the next level, so to speak, and can give without expecting in return. To me, this doesn’t seem like it needs a special explanation however, but can be explained by evolutionary reasoning that exists.