Heredity and Environment

Lesson 6-4

Objectives

Give examples of the effects of heredity and environment on behavior

Summarize research on the effects of heredity and environment on behavior

Heredity and Environment

Is behavior instinctive?– Due to heredity

Is behavior learned?– Due to environment

Heredity- the genetic transmission of characteristics

Heredity and Environment

Inherited factors and environment work together.

Nature vs. Nurture

Has been going on for centuries Nature- what a person inherits Nurture- refers to environment Sir Francis Galton- Heredity Genius

– Analyzed families– Found success ran in families

Heredity and Environment

John Watson- behavior psychologist– “Give me a dozen healthy infants, well-formed

and my own specified world to bring them up in and I’ll guarantee to take any one at random and train him to become any type of specialist I might select- a doctor, lawyer, and yes, even beggerman and thief, regardless of his talents, tendencies, abilitities, and race of his ancestors.

Genes and Behavior

Genes are basic units of heredity

Twin Studies

Study identical twins to see if a trait is inherited– Twins developed from a single fertilized egg– Share same genes

Fraternal Twins– Develop from two eggs– Same as brother and sister

Twin Studies

Also study twins who were separated at birth– Despite different backgrounds, many share

same common behaviors• Do well in math, trouble in spelling

– Drinking patterns

Closure

Research current articles about nature vs. nurture

Would you be in favor of being able to select the behavior characteristics of your children?