Mike Ko Personal Portfolio


Home-School Education
Hong Kong

University of Durham
Bachelor of Science
United Kingdom

University of Sussex

Master of Arts
United Kingdom

Writing - Original

Opinions on Human Behavior from Evolutionary Principles




                        Our world contains numerous animal species, each interacting with other organisms and entire ecosystems as a whole. As humans, we recognized that there are certain patterns in other animals’ lives. Male birds sing to attract mates, wolves hunt in packs, and bee nests have hierarchical division of labor. These and many other behaviors can be interesting, ingenious, and sometimes outright baffling to us. For a long time, humans had few scientific ideas about the reasons why animals exhibit such behaviors. Yet the creation of evolution theory changed all that. Using evolutionary principles, we are beginning to understand animal – and other species’ – behavior to various extents.

                        While progress is being made on animal behavior, it seems we still quite ignorant about ours. Why do people give different response to particular situations? What are the general causes of such behaviors? Many often regard human behavior as complex or even irreducible concepts. Yet humans are ultimately animals (in a technical sense!), so it is reasonable to see if evolutionary principles can explain our behavior. Indeed, it seems to me that such principles do appear to account for certain basic human behaviors. We shall explore a bit more about these soon. If such basic behaviors can be accounted evolutionarily, then perhaps they can also explain more complex ones? To fully appreciate these ideas, we start with introducing some fundamental ideas of evolution.

Behavior as Fitness Maximizing Strategies

                        Generally, evolution is the process of descent with modification: over generations, species undergo biological changes. Such changes can modify specific traits in species’ populations, as well as transform species into completely different ones. Various processes can lead to evolution, and one important one is natural selection. Simply put, natural selection is an adaptation process of species over generations. Natural variations in a species population can provide certain individuals survival and reproductive advantages in particular environments. Such individuals have higher chances of producing offspring, passing on advantageous genes (genetic units) to the next generation. These genes and traits then become more prevalent over time. Thus, natural selection is a process where better-adapted traits (and individuals who have them) proliferate. The important determining factors in natural selection are survival and reproductive capabilities, collectively known as fitness.

                        Yet what is the link between natural selection (and so evolution) and behavior? Generally speaking, individuals of a species can act in specific ways that increases their fitness. Birds sing songs to attract potential mates, hence to reproduce and pass on their genes. Fishes swim in schools to confuse and evade predators, thus increasing their chances of survival. In a sense, different species’ behaviors are simply traits or strategies that maximize survival and reproduction chances. Strategies that are fit shall become more and more common in the population through natural selection. As such, we can reasonably expect that at least some species behaviors are fitness-maximizing (hence prevalent) strategies. Such evolutionary rationale can account for various species’ behaviors and possibly humans’ as well. Let’s look at some possible examples for the latter case.

Possible Human Examples

                        An obvious human behavior that can be attributed to fitness-maximizing strategies is our aversion to death (and its possible causes). This trait is essentially a strategy that increases fitness from a survival perspective. For obvious reasons, death-fearing individuals survive better and reproduce more relative to less fearful ones. Natural selection then selects death-averse individuals, and subsequent generations increasingly inherit this trait. Eventually such advantageous trait becomes widespread, and we are all naturally death-averse in general.

                        Another direct example is our typically constant reproductive urge (at least until recent decades). Like any other organisms, human individuals naturally mate to reproduce, without any explicit dictating logic. Yet this behavioral drive may again be a consequence of fitness-maximization, this time in reproductive terms. In a population, various factors lead different individuals to reproduce at different rates. Whatever the cause, those who are more willing to reproduce shall outbreed those who are less willing. Offering a general fitness advantage, this behavioral trait gets selected and eventually dominates in the human population. So our reproductive urge may be due to greater representation of willing reproducers.

                        Fitness maximization might also explain our tendency (or lack thereof) to help other human individuals. Greedy or selfish behavior may be interpreted as strategies for hoarding resources or other benefits. These can further translate into fitness advantages. Conversely, when individuals engage in altruistic behavior, it can result in survival and reproductive advantages for all. As long as everyone helps others in need, fitness for the population improves overall. Although favors are not always returned, selfless behavior can still be sufficiently advantageous relative to selfish ones.

                        Of course, whether selfish or selfless strategies are more successful (and so selected by natural selection) depends on prevailing conditions. Yet given that both behaviors are observed in human societies, it seems that each have substantial benefits. Note that a different reasoning actually applies to one’s tendency to help relatives. In contrast to aiding strangers, people typically help their relatives readily. Although it may not seem apparent initially, this behavior can also improve one’s fitness {1}.

                        Direct reproduction literally passes on and multiplies particular genes and traits in a population. Fit individuals pass on advantageous ones, becoming more common as they outbreed others. Obviously, how much one reproduces shall directly affect their fitness. However, their siblings’ and to a lesser extent other relatives’ fitness can also play a role. Relatives – especially close ones – have comparatively similar genetic composition. When they reproduce, they pass on comparatively similar genes and traits. So helping one’s relatives (ultimately to reproduce) can also increase one’s own fitness, by passing on similar genes. Eventually, those who help their relatives collectively become fitter and numerous relative to those who do not. Hence, most people tend to help their siblings and relatives (regardless of how willing).

                        Most of these examples are likely to be gross (and possibly wrong) simplifications of human behavior of my own speculations. Many other factors are certainly at play for the above and other kinds of human behavior. Furthermore, various other evolutionary mechanisms and principles other than natural selection can be employed as well. In addition, such behavior may be inherited from humans’ ancestors (perhaps very old ones). Yet in general, it seems plausible that we can derive evolutionary explanations for relatively basic human behaviors. If extendible to more complex behavior, such evolution-based approaches shall greatly increase our understanding of our behavior.

A Promising Direction?

                        Biologists have long seen the potential of this approach. Indeed, there are already several scientific fields that seek to explain human behavior through evolution. For instance, human behavioral ecology studies how human behaviors are influenced by the environment. Another related field is known as evolutionary psychology. In this approach, human behavior can be attributed to behavioral adaptations to past, ancestral human conditions. These and other related fields can shed scientific light upon our behavior, which is often viewed subjectively. However, evolutionary explanations’ may encounter issues. Specifically, conclusively proving evolutionary explanations in general may be difficult, reducing them to speculations in extreme cases.

                        In addition, the above scientific approaches can leave people in uncomfortable positions. We may feel that human behavior is all due to fixed evolutionary rules. In this sense, we react to situations with different but preset responses without any conscious direction, like computers. This may not be entirely the case. Our general behavior can have fitness-maximizing rationales from an evolutionary perspective. However, humans actively adapt to different circumstances in ways that we decide ourselves. These may be influenced by the environment and ultimately serve some fitness-manipulating purposes. But in the end, we control our own behavior at the bottom level. In this sense, the evolutionary rules are just observed patterns that human behavior tends to follow. Yet technically they do not directly fix or limit our behaviors.

                        Evolution-based approaches to human behavior can be really interesting if they are widely applicable. For one thing, they can illuminate differences and similarities between comparatively complex and simple organisms. Humans have long been thought of as superior to other animals (or any other species, for that matter). Yet are our behaviors actually that different, especially if the evolutionary behavioral determinants are identical? Further development in fields like human behavioral ecology and evolutionary psychology can potentially reveal more about human nature. That shall be important in understanding ourselves and our relationship with the rest of the natural world. Such potential certainly warrants further pursuit of deeper understanding about the human behavior from evolution.

                                                                                                                                                                  Mike Ko
                                                                                                                                                                  ( 1,408 words )



    1. "Sense and Nonsense - Evolutionary Perspectives on Human Behavior" by Kevin N. Laland and Gillian R. Brown; Oxford Univeristy Press, 2002


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