VITRUVIAN MAN, C. 1492 – LEONARDO DA VINCI
THE BEGINNING – THE STORY OF CREATION :
The Holy Bible, The Old Testament, Book of Genesis, Chapter 1( verses 1,3,4,5,14 and 15) describes the creation of day and night.
In the beginning God created the heavens and the earth.
And God said, “Let there be light,” and there was light.
God saw that the light was good, and He separated the light from the darkness.
God called the light “day,” and the darkness He called “night.” And there was evening, and there was morning – the first day.
And God said, “Let there be lights in the expanse of the sky to separate the day from the night, and let them serve as signs to mark seasons and days and years, and let them be lights in the expanse of the sky to give light on the earth.”
A SIGN TO MARK SEASON – THE SUMMER SOLSTICE :
In the northern hemisphere, at the Summer Solstice, the day is the year’s longest. It marks the first day of the season of summer. During the year 2008, the Summer Solstice occurred on Friday, June 20 at 7.59 P.M. On this day, the Sun is farthest north from the Earth’s Equator.
SYNCHRONIZATION OF EXTERNAL AND INTERNAL ENVIRONMENT OF LIVING ORGANISMS :
The Biological Clock – Every living system studied behaves as if it contains a highly dependable clock. The specialized properties of this clock suggest that it involves some unique biological mechanism indissociable from life itself.
The Biological Clock is a self-sustained internal timing mechanism that controls cyclic patterns, or rhythms, of a living organism. All organisms have this ability to synchronize their existence to events in both their internal or external environment. Because of this internal timing, certain physiological and behavioural events vary in intensity. Such time-dependent variability is expressed as a rhythm, or oscillation, with a frequency equal to that of the underlying biological clock. Biological clocks time the Solar day, the period of the Earth’s rotation relative to the Sun.
The Biological Rhythm – Biological Rhythms represent the periodic biological fluctuation in an organism that corresponds to and is in response to periodic environmental change. The most important example of such environmental change is that of the cyclical variations in the relative position of the Earth to the Sun and the immediate effect of this variation is that of night alternating with day or the change from darkness to light. Biological Rhythms that occur once a day are called Circadian(Latin circa:”about,” di: “day,”), Solar day, diel, daily, diurnal(day-active), or nychthemeral rhythm. Circadian rhythms are the most pervasive rhythms regulating many events for every day in the lives of most living organisms. Circadian rhythms are synchronized to an external time-giving stimulus. The external stimulus that is important for most living organisms is that of Sun rise and Sun set, the daily light-dark cycle determined by Earth’s rotation.
DAY-ACTIVE OR DIURNAL RHYTHM IN MAN :
Within the 24-hour cycle(circadian), a person usually sleeps approximately 8 hours and is awake 16 hours. In man, the daily alteration of sleep and wakefulness is accompanied by many changes, including activities of the nervous and endocrine systems and the liver and kidneys. Daily variations occur in body temperature, in heart and respiratory rates, and in blood pressure and composition of the blood.There are daily variations in chemical syntheses and in cell divisions.
During the wakeful hours, mental and physical functions are most active and tissue-cell growth increases. During sleep, voluntary muscle activities nearly disappear and there is a decrease in metabolic rate, respiration, heart rate, and blood pressure. The activity of digestive system increases during the resting period, but that of the urinary system decreases. Hormones secreted by the body, such as the stimulant epinephrine(adrenaline) are released in maximal amounts about two hours before awakening so that the body is prepared for activity.
If a person tries to break the circadian rhythm by ignoring sleep for a number of days, psychological disorders begin to arise.
THE LAWS OF NATURE :
Diverse aspects of human physiology and behaviour show that human existence is synchronized with the Laws of Nature. When we live in accordance with the law, we get a chance to know the provider of the law.
A PRAYER TO THE DIVINE LIGHT( GAYATRI MANTRA) :
Om, Bhur Buvaha Suvaha
Tat Savithur Varenyam
Bhargo Devasya Dheemahi
Dhiyo Yonaha Prachodayath.
We contemplate the glory of Light illuminating the three worlds: the physical(the gross), the mental(the subtle), and the spiritual(the causal), we pray for the divine Light to illumine and guide our minds.
Please view related blog post titled ‘Defining Indian Identity – The Light Bulb Connection’
Dr. R. Rudra Narasimham,
Kurnool Medical College, Kurnool, Andhra Pradesh, India,
M.B.B.S., Class of April, 1970.