12 May 2012
Types and Forms of Adaptation
Adaptation is one of the main topics of this blog, since it is the major characteristics of complex adaptive systems. It can be found in multiple fields and many different systems. In anthropology, adaptation is usually defined as the gradual process organisms undergo to achieve a beneficial adjustment to a particular environment [1]. Organisms adjust themselves to the conditions of the environment. Indeed there are as many types and forms of adaptations as there are organisms and systems: biological, psychological, social, and economic systems. Adaptations can range from short term changes in form of temporary adjustments (often reversible) to long term, irreversible changes in form of written, inheritable code changes.
Humans are the ultimate masters of adaptation. They use sunglasses, scarfs and hats to protect themselves from strong sunshine, they wear light clothes in the summer and warm ones in the winter to protect themselves from heat and cold, respectively. Like all mammals they sweat when it is hot and shiver when it is cold. They have adapted themselves to every inhabitable area on earth, from the Arctic to the Sahara Desert. They use fire to adapt to inedible food, and they construct houses to protect themselves from the weather. They adapt their behavior perfectly to the group they live in by learning their language, customs and conventions.
In the past we have considered a lot of different forms of adaptations. What do they have in common? To which system do they belong? Barbara D. Miller distinguishes in her book Anthropology [2] three categories of adaptation: genetic, phenotypic or physical, and cultural. She defines genetic adaptations as “a change that, over a long period of time, has been selected for and thus becomes part of the genetic heritage of a population”. Cultural adaptation is “a learned and shared response to environmental stresses” (for example the use of fire or the construction of houses). Phenotypic and physical adaptations can be found in between in the phenotype: for example in form of a temporary acclimatization to a different climate.
Harrison and Morphy mention in their book Human Adaptation [3] four different basic forms: genetic, physiological, behavioral and cultural adaptation. They affect different organisms and systems, all the way from genetic to cultural systems. Here we consider physiological adaptation as the link between genetic and behavioral adaptation, since physiology is situated between biology and psychology (at least physically). Anthropology comprises all of these different forms of adaptation, because all of them concern humans. It can be considered as a link as well, only from an evolutionary perspective.
Genetic Adaptation
Affects physical properties of biological organisms (plants, animals, ..) in general, esp. humans as biological organisms. Biological evolution and natural selection determine how animals look like. They result in the particular shape, specific form and individual appearance which is encoded in the genes. Long term changes involve permanent, inheritable changes of the genetic code.
Physiological Adaptation
Affects physiological properties based on genetic changes which control the behavior: Emotions, Feelings, Depression, Stress, Intelligence. Physiological refers to organic or bodily processes of an organism. Physiological adjustments are short-term changes in response to environmental conditions: presence of predators or prey, climatic conditions (very low or very high temperature), etc.
Behavioral Adaptation
Affects properties of cognitive and psychological systems (adaptive lifeforms), esp. humans as intelligent beings: Arrogance, Kindness, Brevity, Intelligence . Our personalities are complex products of multiple factors. In general, as in all evolutionary systems, favorable variations tend to be preserved. Some of our behaviors are more successful than others. We tend to keep those which are successful and drop those which are not. The result after a long path-dependent development is our “character” or “personality”.
Cultural Adaptation
Affects properties of cultural systems (cultures, companies, corporations) with “cultural DNA” esp. humans as social groups: Anonymity, Tolerance, Corruption. Long term changes involve permanent, inheritable changes of the corporate identity or “cultural DNA” code.
References:
[1] Cultural Anthropology: The Human Challenge, William A. Haviland, Harald E. L. Prins, Bunny McBride, Dana Walrat, Wadsworth Publishing, 2007
[2] Anthropology, Barbara D. Miller, Pearson, 2006
[3] Human Adaptation, G.A. Harrison and Howard Morphy (Editors), Oxford University Press, 1993
( The sunglasses picture is from Flickr user Hamed Saber )