Nature and Nurture in Human Development - In Depth Notes

Influence of Nature and Nurture on Human Development

• Developmental psychologists explore how genetics (nature) and environmental factors (nurture) shape human growth and behavior.
• Nature: Refers to biological inheritance, particularly genes.
• Nurture: Encompasses environmental and social experiences impacting growth.

Research Methods

• Twin Studies:
  • Researchers study identical twins (same genotype) to assess genetic influences.
  • Fraternal twins share only 50% of their genes, allowing comparison of genetic vs. environmental influences.
• Adoption Studies:
  • Examines similarities with biological vs. adoptive families to assess nature versus nurture.

Genotype vs. Phenotype

• Genotype: The genetic makeup of an individual (actual genes).
• Phenotype: Observable traits influenced by genotype and environment.
  • Example: A recessive gene may not be expressed in phenotype if paired with a dominant gene.

Environmental Influence on Genetic Expression

• Example of Phenylketonuria (PKU):
  • Caused by two recessive genes leading to an inability to metabolize phenylalanine.
  • With a low-phenylalanine diet, individuals can avoid severe developmental impairments traditionally associated with PKU.

Interplay of Nature and Nurture

• Development results from the interaction of genetic and environmental factors.
• Good nutrition can influence the expression of genetic potential (e.g., height).

Developmental Systems Perspective

• Researchers increasingly recognize that development is an ongoing process influenced by biological, psychological, and social factors.
• Urie Bronfenbrenner's Ecological Systems Theory (1977):
  • Highlights how individuals are influenced by multiple environmental layers: family, school, neighborhood, and larger cultural contexts.
  • Persistent poverty has long-term effects on development, making interventions targeting poverty critical.

Role of Individuals in Their Development

• While genes and environment set the stage for development, individuals also play a role in shaping their own development.
• The concept of actively seeking optimal experiences and shaping life pathways is essential in personal development.
• Notable individuals (e.g., Martin Luther King Jr., Mother Teresa) have transformed their experiences and made significant contributions despite early challenges.