1. Genetics A Psychological Perspective

2. Behavioral Genetics • Understanding how both genetics and the environment contribute to individual variations in human behavior. • Genetics are extremely complex • We share 93% of genes with rhesus monkeys, so the 7% is responsible for unique behaviors. • It is not possible for one gene to be responsible for complicated behaviors such as intelligence, attachment, criminal behavior, etc.

3. Inheritance • Genes that are passed down from parents to their off-spring • Humans are composed of 23 (down syndrome 23 + 1 Chromosome) pairs of chromosomes • 20,000-25,000 genes • James Watson: Human Genome Project • 1990-2003 • Mapped human genes • Regardless of this amazing accomplishment, the role of specific genes are still unknown

4. Genetic Research • Based off of correlational studies • Independent variable is not manipulated, so no cause and effect can be determined. • Three types: • Twin Studies • Family Studies • Adoption Studies

5. Twin Studies Monozygotic (MZ) Dizygotic (DZ) • Identical: one egg split in two • Share 100% of genes • Same sex • Fraternal: Formed from two separate eggs • Share 50% of genes just like any other siblings • Same or different sex Used as basis for hypotheses since they show the different degrees of genetic relationship. In twin studies the correlation found is known as concordance.

6. Family Studies • More representative of the general population • Different degree of relatedness is compared with behavior to determine the impact of genes.

7. Adoption Studies • Used to determine how great of an impact environment plays in behavior since the child does not share any genes with foster parents. • Often criticized because of selective placement • Agencies tend to find adoptive parents that are similar to their biological parents which cause a difficulty in determining separating genetic inheritance from environment influences. This process is known as selective placement.

8. Theory of Natural Selection • Members of a species acquire adaptive behaviors to survive the ever-changing environment (those better suited for environment will breed and pass on characteristics) • Adaption: Species develop characteristics that make it more competitive in its environment • Charles Darwin • On the Origin of Species • Descent of Man

9. The Descent of Man findings • We humans share several behaviors with other animals • Mate selection • Love of mother for offspring • Self-preservation • Similar facial expressions as apes • Similar feelings as animals

10. Natural Selection Video • http://youtu.be/Pt2gHpqfZNA

11. Monkeys vs. Humans • Tetsuro Matsuzawa (2007) • Looked at spatial memory in young chimps • Used 3 chimps that were taught to recognize the numbers 1-9 on a computer • Humans and chimps saw number flashed on a touch screen monitor and then the numbers were covered with blank squares and then were asked to touch the squares in sequential order. • http://www.youtube.com/watch?v=Gf3_JrTEGW0

12. Findings • Humans had more errors and less accuracy as numbers were flashed and replaced by squares quicker • As agriculture developed, spatial memory skills aren’t as important for finding food • Perhaps this skill was replaced by the ability to develop language • Chimps had astonishing memory; no difference in their recall in relation to the amount of time that the numbers were replaced with squares. • Adaption for survival skills such as remembering where food and danger is located in the rain forest