Biological & Maturational Bases of Development: Evolutionary Perspective

Human mind is a great mystery. ‘How a human mind designed?’, ‘What are the functions and capabilities of it?’, ‘How does mind work, when learning occurs?’. All of these questions are belong to the field of ‘Evolutionary Psychology”. Evolution refers to change over time in living structure. ‘Evolution Theory’ studies how the features typical to species affect themselves and how all species differ from each other. The word of ‘evolution’ makes us recall Darwin. However, there are many other scientists who worked on evolution.

Greeks thought that all things are originated from water or air. They considered that there is only one center and all other species are modifications of it. Aristotle supposed that all species have constant desire to move from the lower to higher. Following, Medieval Theories assume evolution as out of fashion and supported Christianity –spontaneous generation-, as we call it now ‘creationism’. However, this way of assumption prevented scientific thinking. It is a matter of belief and religion, but not a scientific point of view. Therefore, it can never be proved false. ‘Creationism’ is one of the major theories, which has been proposed against ‘Evolution Theory’ in our modern world. Likewise, Immanuel Kant also had some assumptions on evolution. He suggested that orangutans and chimpanzees could be the origins of human kind. We can relate Kant’s thoughts to Darwinian thinking. Besides Darwin, his grandfather Erasmus Darwin was also a naturalist and studied on single common ancestor effects of competition and sexual selection. However, he never thought about natural selection. Like Lamarck, Erasmus Darwin supported a theory, which states that the use or disuse of parts could make these parts grow or shrink. Lamarck gave an example of giraffes, that they evolved long necks because they gradually get used to eat leaves from tall trees. However, giraffes have long necks not because of the Lamarck’s ‘use and disuse of parts’ theory, it is because of the shorter giraffes sieved by the natural selection. Also, Lamarck suggested that an organism could pass on to its offspring any characteristics it had acquired in its lifetime. However, when we think about the concept of ‘inheritance’, this suggestion seems obviously wrong. Because, the changes had occurred on individuals throughout their lifetime cannot be brought or transferred by genes. For example, think about a person who got a head injury because of a traffic accident or a person who got fit through cardio. Does it mean that, also their children will have an injury from head or will have an athletic body?

Adaptation is the key point in evolution. However, this doesn’t mean that every change will transfer through genes to other generations, rather, it refers to solving survival problems and forming the appropriate conditions for next generations i.e. turtle’s shell, umbilical cord.

Survival is necessary for every living kind. To be able to survive and pass its inherited qualities to future generations species must reproduce. Therefore, we have to understand ‘sexual selection’. This theory focuses on consequences of successful mating rather than natural selection’s subject of interest successful survival. Sexual selection gets interest with the features that make species to reproduce. i.e. Peacock’s plumage evolved to impress the opposite gender.

Besides all the ingredients of evolutionary theory it is also important to remember its characteristics. Natural and sexual selection are not the only causes of evolution, it can also occur through genetic drifts like mutation. Additionally, evolution is not intentional and forward-looking. It is gradual and takes hundreds of years to occur.

‘Evolution Theory’ is one of the greatest theories that have ever been studied. There had been lots of objections to this theory, however, none of them was able to disproof it. Many scientists made and still make further developments on this theory. Although there are still lots of questions to be answered and some complicated conditions, we cannot deny the acquisitions of this theory, because it made possible for us to better understand our world.

Concepts and Theories of Human Development

For centuries scientists and philosophers have studied on concepts of child and development. There are mainly three paradigms in development; cognitive, behavior and social aspects of it. When we try to understand how a child acts and what is the meaning of development, first we have to define what is being child? Child is defined as:

1.     Biologically, a child is a human between the stages of birth and puberty. The legal definition of child generally refers to a minor, otherwise known as a person younger than the age of majority.

2.     Child may also describe a relationship with a parent (such as sons and daughters of any age) or, metaphorically, an authority figure, or signify group membership in a clan, tribe, or religion; it can also signify being strongly affected by a specific time, place, or circumstance, as in "a child of nature" or "a child of the Sixties". [1]

So, what can we understand from these dictionary definitions? We can assume that stages of child development are universal. Approximately every child gets through from the same stages averagely in the same age. It is for sure that, a child development depends on nature features like heredity, maturation or genes. However, one thing that we can’t assume is, every child in the same age group will have the same characteristics and same level of maturation. Development also derives from nurture. Environment, experience or learning has great influence on child development. In the second definition of a child, it is directly related with nurture concept. In social learning theory, Albert Bandura (1977) states behavior is learned from the environment through the process of observational learning.  Children observe the people around them behaving in various ways. [2] Likewise, in social learning theory environment has a huge impact on the formation of the child’s evolution.

While child is developing, there is a continuous process of learning. Learning can be defined as persistent change in behavior. Fully comprehending of learning can be ensured by some questions like; ‘Which behavior has changed? , ‘How it changed?’ or ‘Is it a quantitative/qualitative change?’.

However, nature and nurture are not the only aspects that have an influence on development of a child. And all the other perspectives form developmental systems. For example, think about twins. Twins have the same genes and heredity, therefore nature is not a discriminating factor for them. Also, assume that they grow up in the same environment. Then, again nurture can’t be count as the distinctive factor. So, what concept makes twins two different characterized person? In this point Thelen&Smith notion the ‘Dynamic System’. In this system of development, all layers of development interact with each other and individuals self-regulate themselves according to their environment. It is not about the cause and effect relationship, but it is about the individual’ active participation in the evolutionary process. Instead of the Dynamic System, Bronfenbrenner argued that individuals could be affect from the layers of development; eventually they determine the way they develop themselves.

Furthermore, ‘Life-Span’ theory is about life long learning and adaptation of individuals to their environment. Besides, ‘Action Theory’ cares about individuals being active in their social surroundings. Plasticity and ontogeny of individuals are important factor in this theory. Aside from, ‘Life-Course Theory’ sees human development as an interpersonally relational process. The distinctive features of life-course theory are associated with the link that Elder drwas between individual development and the social relationships within which the person’s ontogeny is dynamically collaborative.[3]

In addition to theories of development, many concepts should be considered in order to understand how development occurs and what concepts influence it’s occurrence.

References;

[1] http://en.wikipedia.org/wiki/Child

[2] http://www.simplypsychology.org/bandura.html

[3]Developmental Science, An Advanced Textbook, Fifth Edition, Marc H. Bornstein, Michael E. Lamb