 Total of 46 chromosomes-threat like structures made of DNA molecules that contain genes › 23 from mom and 23 from dad › DNA: contains genetic information › Genes: biochemical units of heredity › Book example

 Genes can be active or inactive  Environmental events “turn on” genes › When turned on, they provide the building blocks of physical development  Human genome: common human DNA › Share 96% of our DNA with Chimps  Most of our traits are influenced by many genes › Physical to Intelligence › u_TDFc

 Identical: develop from a single fertilized egg that splits in two genetically identical › Share same genes, but may vary on the number of copies of those genes › Some are mirror images of each other: left vs right hand or have different personalities  Fraternal: develop from separate fertilized eggs  dJgeyvc

 Read Case Studies page  Conclusions based on the reading?  What do we need to be careful about regarding separated identical twin studies?

 They continued to find similarities not only to taste and physical attributes but also of personality, abilities, attitudes, interests, and even fears  Remarkable similarities in life choices, support the idea that genes influenced personality  Greater appreciation of genetic influences  Don’t over generalize!  hemS_0

 Parents vs. Adoptive Parents  Hereditary shapes personality › Adoptees more similar to biological parents in personality than adoptive parents  However, parents due influenced their child’s attitudes, values, manners, faith, and politics  Most adoptive children thrive › Self-giving parents: children become more self- giving, score higher on intelligence tests than biological parents

 The extent to which variation among individuals can be attributed to their differing genes. Rather it explains that 50% of the observed variation among people  Just because a trait is heritable does not mean it will affect an individual  We can never say what % of an individual's personality or intelligence is inherited

 Individual differences in height and weight are highly heritable yet nutritional rather than genetic  Heritable individual difference need not imply heritable group differences › Ex: Putting people in a new social context can change their aggressiveness

 Environment triggers gene activity  Genetically influenced traits evoke significant responses in others  We select environments suited to our natures  Think nature via nurture

 Molecular Genetics: identify specific genes influencing behavior  Goal is to find some of the genes that influenced normal human traits such as body weight, sexual orientation, personality, and mechanism that control gene expression

 Genetics tests can reveal at-risk populations for many diseases  Medical personnel are able to provide parent with a readout on how their fetus gene’s differ from the normal patter › Double-edged sword? Problems? Discrimination?

 Focus on what makes humans so a like and use Darwin’s theory on natural selection to understand the roots of behavior and mental processes

 Darwin  When certain traits are selected by reproduction those traits will prevail  Genes allow us with a great capacity to learn and adapt to life in varied environments

 Shared human traits shaped by natural selection  Shared human genome  Outdated tendencies: crave sweets and fats

 Gender differences in sexuality  Natural Selection and Mating preferences › Ancestral History: Women more relational, choosing wisely Men more recreational, pairing widely › Today: Women attracted to more mature, bold, dominant, affluent. Men youthful/fertile appearance (WHY?)

 What’s considered attractive does vary time and place  Cultural expectations can bend genders  Social expectations and mate preferences  How we came to need does not dictate how we ought to be