Development and its influences

Development is the pattern of progressive, orderly and predictable changes that begins at conception and continues until death. It includes growth and also decline: memory and physical strength can fall in old age, and that is development too.

It is not only about the body getting bigger. A small child believes a cartoon hero is real; a teenager reasons logically. A toddler throws tantrums; an older child learns to manage feelings. Development covers three interwoven processes, each affecting the others:

• Biological: changes in the body, brain and hormones.
• Cognitive: changes in thinking, memory, language and reasoning.
• Socio-emotional: changes in relationships, emotions and personality. A quarrel at home can upset your concentration (emotion affecting thinking), and stress even changes body chemistry.

Related words:

• Growth: increase in body size and parts.
• Maturation: changes that follow the genetic blueprint, such as being able to walk when the body is ready.
• Evolution: change across species over very long periods, not within one life.

The life-span perspective makes seven points. Development is:

• Lifelong (gains and losses at every age) and multidimensional (biological, cognitive and socio-emotional).
• Multidirectional (some abilities expand while others shrink) and plastic (it can be changed; skills can improve or fall with the right or wrong surroundings).
• Shaped by history (what happened earlier, such as a cold, uncaring first year, can affect the adult), multidisciplinary (studied in psychology, sociology, anthropology, medicine) and contextual (it responds to the person's setting: genes, family, culture, facilities).

Genes and environment. We inherit genes from our parents. The genotype is the actual genetic material. The phenotype is how the genotype shows up in observable traits, as a result of genes and environment working together (nature and nurture). A child may inherit a good ear for music, but whether she becomes a skilled singer depends on practice, teaching and encouragement.

Genes set the limits of what is possible; the environment decides where within those limits a person ends up. As Sandra Scarr argued, parents' genes and the environment they provide work together, and children also seek out surroundings that suit their genes.

Bronfenbrenner's ecological model places the child at the centre of nested systems:

• Microsystem: the immediate setting: family, school, friends, neighbours. It has the strongest influence.
• Mesosystem: links between parts of the microsystem, such as a parent-teacher meeting.
• Exosystem: settings the child is not directly in that still affect them, such as a parent's workplace, mass media, local services.
• Macrosystem: the culture's beliefs, values and customs.
• Chronosystem: changes over time, such as a parent's death or how worries that seem huge at 15 look small at 25.

Durganand Sinha adapted this to the Indian setting with two layers: an upper layer of visible influences (home, school, peers, playgrounds) and a surrounding layer of less visible ones (the physical environment, institutions, caste and class, cultural ideas).