In the last issue I mentioned that human growth is a broad concept that encompassed both internal and external development of the body. Therefore various steps and processes are involved from the very inklings of life (i.e. the fertilized egg) to when one becomes an adult. When we examine this diverse and vivid phenomenon, although it is overly complicated, we are able to detect five strong principles in this developmental process. Today, I would like to discuss further this "the principle of development".
I believe that there are five principles of development. The first phenomenon is that there is an "order" that nature's course takes. That is, there is a certain order followed in the process of development.
The molecular structure that became the prototype of life three billion five hundred million years ago on this earth, is the origin of the order or path. Two to three billion years ago, the molecular structure evolved into a multi-celled organism which evolved into animals, plants and vertebrates. It is conceivable that even the genes that run through our bodies presently could possibly be from our predecessors from 400 million years ago, that is plants, fish, reptiles, dinosaurs, and mammals. Therefore, the order that is observed in the development phenomenon is already determined at the gene level.
The development of the fetus, in the mother's womb and the development of the internal organs advances in a similar order. Furthermore, the baby's motor development can be observed to proceed in the same order. First, the baby is able to hold his/her neck alone, which is followed by sitting alone, then crawling, subsequently standing while holding on to something, then walking with the aid of an adult, and finally walking by oneself.
Certainly, reflecting the diverse nature of gene constitution, differences in the period of onset of these milestones may be observed. Some children may be quite early, while others quite late. The advantages and disadvantages for these differing onsets can also be observed as a different function in each child. This, in short, can be accounted for as individual differences.
Recently, there are babies who skip the crawling stage altogether and suddenly stand while holding on to something and eventually begin walking. The period of this particular motor development (i.e. crawling) is perhaps, remarkably short and hardly noticeable which can be considered a violation of the principle of order.
My speculation is that the Japanese child had been raised in a tatami room, which incorporated few pieces of furniture, but recently, with the Westernization of the living space and the addition of table and chairs in the room, this order may have become altered. The baby merely finds more objects in his/her environment that are easier to grasp on to and begin standing. Thus, it is the environment that is influencing this aspect of the timeline of development, and not a physical dysfunction of the baby.
The second principle is the variance in development speed. I would like to think about height in terms of the speed of growth because it is one aspect of development that is measurable by a standard guideline.
The speed that one grows is especially accelerated in the fetal period and in adolescence. This is apparent in just imagining the fertilized egg growing in a period of nine months to be about 50 centimeters by the time of birth. Moreover, during the last stages of pregnancy, the fetus grows rapidly and is noted as being more rapid than during adolescence.
Thus, accelerated growth occurs from embryo to fetus to newborn and begins to decelerate after birth. However, the growth continues constantly from this point on until adolescence, when we are able to see accelerated growth at this point once again.
With the onset of adolescence, a growth spurt occurs until about the age of fifteen or sixteen years. At this point, growth begins to decelerate again and by the age of twenty, one reaches his/her full height. From this period on, when one reaches adulthood, there is little growth in height and the speed of growth halts to almost zero.
I believe that there are five principles of development. The first phenomenon is that there is an "order" that nature's course takes. That is, there is a certain order followed in the process of development.
The molecular structure that became the prototype of life three billion five hundred million years ago on this earth, is the origin of the order or path. Two to three billion years ago, the molecular structure evolved into a multi-celled organism which evolved into animals, plants and vertebrates. It is conceivable that even the genes that run through our bodies presently could possibly be from our predecessors from 400 million years ago, that is plants, fish, reptiles, dinosaurs, and mammals. Therefore, the order that is observed in the development phenomenon is already determined at the gene level.
The development of the fetus, in the mother's womb and the development of the internal organs advances in a similar order. Furthermore, the baby's motor development can be observed to proceed in the same order. First, the baby is able to hold his/her neck alone, which is followed by sitting alone, then crawling, subsequently standing while holding on to something, then walking with the aid of an adult, and finally walking by oneself.
Certainly, reflecting the diverse nature of gene constitution, differences in the period of onset of these milestones may be observed. Some children may be quite early, while others quite late. The advantages and disadvantages for these differing onsets can also be observed as a different function in each child. This, in short, can be accounted for as individual differences.
Recently, there are babies who skip the crawling stage altogether and suddenly stand while holding on to something and eventually begin walking. The period of this particular motor development (i.e. crawling) is perhaps, remarkably short and hardly noticeable which can be considered a violation of the principle of order.
My speculation is that the Japanese child had been raised in a tatami room, which incorporated few pieces of furniture, but recently, with the Westernization of the living space and the addition of table and chairs in the room, this order may have become altered. The baby merely finds more objects in his/her environment that are easier to grasp on to and begin standing. Thus, it is the environment that is influencing this aspect of the timeline of development, and not a physical dysfunction of the baby.
The second principle is the variance in development speed. I would like to think about height in terms of the speed of growth because it is one aspect of development that is measurable by a standard guideline.
The speed that one grows is especially accelerated in the fetal period and in adolescence. This is apparent in just imagining the fertilized egg growing in a period of nine months to be about 50 centimeters by the time of birth. Moreover, during the last stages of pregnancy, the fetus grows rapidly and is noted as being more rapid than during adolescence.
Thus, accelerated growth occurs from embryo to fetus to newborn and begins to decelerate after birth. However, the growth continues constantly from this point on until adolescence, when we are able to see accelerated growth at this point once again.
With the onset of adolescence, a growth spurt occurs until about the age of fifteen or sixteen years. At this point, growth begins to decelerate again and by the age of twenty, one reaches his/her full height. From this period on, when one reaches adulthood, there is little growth in height and the speed of growth halts to almost zero.
