True altruism refers to the behavior of an individual that increases the fitness of another individual at the expense of its own fitness. Some proposed examples of altruistic behavior including grooming, warning that a predator is near, and caring for your young. Are these really altruistic though?
In order to decide if these behaviors are truly altruistic, a better understanding of "fitness" is necessary. To an evolutionary biologist, fitness describes the ability of your offspring to survive and reproduce and takes into account your offspring’s contribution to the gene pool of the next generation. In other words, a more fit individual lives longer and in turn reproduces more, which allows for its genes to become more dominant in its children’s generation. If the genes inherited by the next generation increase their fitness, the genes will become more and more common with each successive generation. This repeated process of selecting the most fit genes is called natural selection and is a cornerstone to the theory of evolution.
I’d argue, based on our definition of true altruism and our understanding of fitness that there isn't one example of altruistic behavior in neither the “animal world” nor in our own conscious decisions. Let’s take the three examples I mentioned previously and think about why they aren't truly altruistic.
Social grooming is the act of cleaning another's body, usually involving the removal of dirt and twigs, parasites, and insects from the fur, feathers, scales, or skin. Primates may provide the best example of this activity. Nearly everyone has seen a nature documentary where a baboon is carefully combing through the hair of another, looking for what seem to be tasty morsels. Is this really altruistic? The short answer is no; social grooming plays an important role in maintaining alliances and dominance hierarchies, for reconciliation after fights, and is exchanged for other resources including sex and food.
Caring for Your Young
Caring for your young, through protection and providing them with food, may be the most selfish act one can do. By helping ensure that your young make it to a reproductive age you help ensure that your genes make it to the next generation.
Alarm signaling is a type of signaling used by social animals to warn others of the presence of a predator. This warning system puts the alarmer (the individual making the signal) in more danger by calling particular attention to it. As altruistic as this sounds, this behavior is also very much a selfish behavior. By saving the lives of its social group, many of which are likely closely related, the alarmer is increasing the survival rate of shared genes. These shared genes don't necessarily have to be passed down by the alarmer to be counted towards its fitness. If your sister produces a child because you saved her at the expense of your own life, you’ve still conserved (on average) about 50% of your own genes (you share about 50% of your genes with your siblings). If you saved several of your relatives, just think of the rewards! For a nice table showing the relatedness among different relatives check out this link. You'll see that even saving your second cousin has some advantage.
Now you may be thinking, well those are animals. We humans, with our elevated ability to think, truly have altruistic behavior. I’d still disagree with you. While humans have engineered a way to escape the normal means of natural selection (through modern medicine), people are still awarded for their good behavior, either through direct benefits such as recognition or through intrinsic benefits such as personal gratification. Think about that the next time you do something nice for someone!
For an entertaining look at how their truly isn’t a selfless good deed, check out this great clip by the show Friends.
Don’t forget to check out all the other great articles on FTDM! Stay hungry!