The human life cycle is approximately 75.3 years, according to Tulane University. It is dependent on genetics, culture, environment, social relationships, adaptation to stress, and ability and desire to sustain human existence. The human life cycle begins with the joining of a sperm and egg. Once fertilized, the combination produces a human infant in about nine months. If infants get proper nutrition, health care and protection, they mature through adolescence, adulthood and old age.
Biological and Genetic
According to Gordon College of Georgia, human genetics are influenced by the environment, hormones, light, nutrition, behavior and stress hormones such as cortisol that may cause an increase in DNA damage. The human lifespan is biological and genetic. Human DNA (the genetic information that determines human characteristics) chromosomes contain human genes that determine traits of human existence, but health, happiness, and energy intake and output can alter a person's destiny as noted in the Biological Beginnings lecture from Gordon College. The human reproductive process begins the cycle of life, joining the DNA and chromosomes of two distinct beings, both positive and negative attributes.
Social and Environmental
Abraham Maslow, author of Maslow's Hierarchy of Needs, wrote that the human life cycle is based on the species' ability to meet a series of needs--physiological, security, emotional, social and spiritual. B.F. Skinner developed the social learning theory of behaviorism that says human existence is based on reward, social conditioning and a person's ability to develop based on responses to external events. Erick Erickson developed stages of human development based on humans' ability to develop trust, autonomy, independence, identity, the ability to develop relationships and ultimately to find a sense of productivity. All three theorists indicated that humanity advances based on its ability to meet basic needs for existence and develop a sense of belonging, trust and purpose as well as the ability to adapt to environment.
Learning Theory
Albert Bandara, a social learning theorist, said humans advance by observing the behavior and outcomes of others. This adaptive learning environment develops into a permanent change in behavior. Bandara also notes that awareness and expectations of future reward or punishments can have a major effect on the behaviors that humans exhibit. This social learning theory is applicable to adolescent social and peer behavior that bases advancement on popularity and the rewards that popularity reaps as well as the immediate gratification of popularity.
Social Beings
The human life cycle includes the biological, social, emotional and mental development of the species. They are born of sperm and egg, but are unique beings in that they ask the philosophical question: What is the value of human existence without relationships? Humans are more than their genetics and have the potential to reach beyond the species' evolutionary maturation or succumb to base needs. Males and females survive and thrive through environmental and social mores that encourage interrelationships developed for the advancement of humanity.
Aging Theory
Once humans have lived beyond the need to produce, develop relationships, reproduce and remain productive in society, the search continues for meaning and value. The older human age 65 and beyond strives to continue the human life cycle by generating continued productivity with family, peers, social organizations and finding a way to pass on a lifetime of knowledge as teachers and caretakers. In many other cultures, the elderly are revered as they share with the young their lifetime of experience from human error and human history.
References
- Honolulu, Hawaii Education: Erickson's Stages of Development
- Bio Net Online: How Long Can We Live?
- Prentice-Hall, Theories of Development--Kohlberg's Stages Of Moral Development
- Webspace Ship Education: Personality Theories by Abraham Maslow
- Tulane University: The Human Life Cycle -Foundations in Medicine
