Psych 350 1st Edition Lecture 7 Outline of Last Lecture I Down syndrome II Norm of Reactions III Simple Genetic a PKU b Fragile X syndrome c Williams syndrome Outline of Current Lecture I Identical Twin Study II Variance III Environmental Affects IV Behavior Genetics Study Current Lecture correlations for id twins reared apart and reared together for a variety of physical and psychological characteristics R A fisher wrote paper when he was developing the analysis of variation directly interested in trying to understand the relationship between genes and traits variability in data and divide it into pieces and the pieces are the factors in your variance example interested in reading achievement have various ways to teach children to read iq split into pieces one piece reflect genetic relationship and another reflect the environmental relationship heritability single number from 0 1 and tells you how strongly that trait is total variance in a trait due to the genes example for heritability plant coffee growing plants different types of coffee seeds have specific strengths 7 different types of seeds all the other factors were the same some plants will be big and produce lots and other will be small and produce little how much of that variability is due to difference in environment or genes if growing up in an identical environment then height can not be due to differences in height all of it has to be due to the genesVARIABILITY 100 is due to genes These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute and 0 is due to the environmentheritability is 1 take one of the seed types for the next experiment have three different environments change the altitude or amount of sunlight or water plants grow to different height how much is due to genes and how much is due to environment no difference in the gene all the difference is due to the environmentheritability is 0 because it is all the environment just because something is highly heritability doesn t mean it cant be changed or modified does not mean the environment has a small effect on it north and south Korea two different countries but the whole place they are very similar but people in north Korea is 6 inches shorter than south Korea due to malnutrition height is the most highly heritable trait but the environment can have an effect number you come up with depends on population heritability doesn t mean the environment has no effect fisher total variability into genetic part and environmental part divided into three arts part 1 genetic heritabilitypart2 environmental part is divide into two parts shared environment and unshared environment shared environmental effects effects that cause people to be similar kids within a family some things within that environment will make the kids the same diet climate income unshared kids parents treating their kids differently kids are different and born at different times parents get divorce kids are of different ages environmental event is parents getting a divorce same event but affects the kids differently du to the different ages of the kids two brothers had different opinions on a dollar bill similar to siblings less than 20 percent of the time children are completing for the love from their parents children will specialize in different things one child can be very smart so the other child can be a good athlete different ages events that happen in family will effect children are treated differently based on different personalities families are comparison machines one child is extraverted one is sociable introvert different groups of friends behavior genetics study from ten years ago how heritable is iq looked at levels of iq at different socioeconomic statussocio economic status of 0 low status of income and job high ses children iq is highly heritable largely due to genetic differences green low ses children iq is low heritableenvironment is dominating iq in some situations single mom bad diet no cognitive activities lower iq two parents poor but children read book a lot higher iq papers written about how the genes effect the environment three ways passive link your biological parents have certain genes and they passed them onto you parental environments will be similar to infant environment parents who are shy pass that trait on and the parents will be shy and stay home a lot with baby evocative arousal response to stress some babies are nice and happy nothing bothers them smile a lot others are crabby don t like people cry a lot those behaviors will change mother or fathers behavior active link child is actively choosing athletic child getting involved in sports