Psychology 1000 Chapter 4
September 30, 2013
** Additional slides are being poste for chapter 3
TEST: 75 M.C. questions (60 text and class)
Chapters 1-4 plus appendix A worth 20%
Genes and Evolution
Jim Lewis and Jim springer (first page of textbook) READ
Separated at birth and reunited at 39
o First wife - Linda
o Second wife – Betty
o Hobby – Woodworking
o Job – Security guard/ Sheriff constable
o Smoked – Salem
o Drink – Miller Lite
o Son – James Alan
Psychologist Tom Buchard
20 year study
Hippocrates – suggested that semen contains some sort of design for the formation of offspring.
o Partially correct
Gregor Mendel – a monk performing research with garden peas in the 1860s lead to the
beginning of modern genetic theory.
Dominant and recessive genes
One of the reasons that genotypes differ from phenotypes is that genes are dominant or
If you receive a dominant gene from your mother or father then the particular characteristics
will be present
For a recessive gene, the characteristics fo it will not show up unless BOTH genes from your
mother and father are recessive.
We get half our genetic material from each parent
Therefore, probability of sharing any particular gne with one parent is 50%
Same with siblings Genotype
o The specific genetic makeup of an individual.
o One’s genotype is present from conception and never changes.
o The observable characteristics produced by the genetic makeup.
o Phenotype can be affected by genes and by the environment.
Fatal Familial Insomnia
The phenotype of the individuals gives no indication of the disease….but the genotype is
programmed at the birth and the disease is dormant until mid-life.
Something triggers the onset of the genetic disease and the results are irreversible.
Genes and Intelligence
o can do crazy math problems in his head with no calculation
o Also claims he can learn a new language in just one week
o IQ between 190-210
o Mind blowingly smart
Genes and Evolution
Some believed that species didn’t change, they were just knocked off by God (catastrophic
events) – this was called Catastrophism.
Flora and fauna have changed over time
Fossil record showed this to be true
First, stuff has changed over time. Present animal and plant species are different than extinct
species and more recently extinct species are different than more distantly extinct species. It wasn’t
really clear why this would be so back then. Some argued that there really wasn’t a change in
species that existed, but rather some of the species were knocked out by catastrophic events and
then God created life anew – catastrophism. But, many naturalists at the time didn’t really buy that.
Taxonomic relationship among living things
Obvious relationships existed among different organisms (different birds, different trees,
different fish, etc.)
Stuff could be assigned to natural categories The second problem was that there are obvious categories that plants and animals could be
assigned to. Things we call birds look and act different than things we call trees and things we call
cats, etc. There were ideas about this, some of which viewed these categories as successive
approximations at perfection – scala naturae (this goes back to Aristotle and you still see it creep
into science occasionally, espeically Comparative Psychology) , but again it wasn’t a great
• Species have traits that seem to have special functions
• Different traits for different jobs
– E.g. heart, lungs, eyes, ears, etc,
– E.g. beaks, teeth, feathers, etc.
• Presented his explanation in 1859 in his book, On the Origin
of Species by Means of Natural Selection
• Species “descended with modification” from ancestral species
• “Natural selection” is the mechanism for descent with modification
• Almost 30 yrs after the Voyage of the Beagle, Darwin published his solution to these problems.
Others were beginning to hint at the same solution but nobody explained it as convincingly as
• He published his explanation in this book. He was actually kind of slow in getting his book
published and in fact, one day received a manuscript from a guy named Wallace – the