powerpoint presentation for biopsychology…drrobingoins.com/assets/chapter_2_ppt.pdf · for...

POWERPOINT PRESENTATION

FOR BIOPSYCHOLOGY,

9TH EDITION

BY JOHN P.J. PINEL

P R E P A R E D B Y J E F F R E Y W . G R I M M

W E S T E R N W A S H I N G T O N U N I V E R S I T Y

COPYRIGHT © 2014 PEARSON EDUCATION, INC.

ALL RIGHTS RESERVED.

This multimedia product and its contents are protected

under copyright law. The following are prohibited by law:

• any public performance or display, including

transmission of any image over a network;

• preparation of any derivative work, including the

extraction, in whole or in part, of any images;

• any rental, lease, or lending of the program.

Thinking about the Biology of Behavior

Chapter 2

Evolution, Genetics, and

Experience

Copyright © 2014 Pearson Education, Inc.

All rights reserved.

Learning Objectives

LO1: Thinking about the biology of behavior in terms of traditional physiological-

psychological and nature-nurture dichotomies is flawed: Explain and discuss.

LO2: Summarize the pathway of evolution from single-cell organisms to humans.

LO3: Describe 8 commonly misunderstood points about evolution.

LO4: Discuss the field of evolutionary psychology and the study of mate bonding.

LO5: Outline the mechanisms of gene expression.

LO6: Discuss several ways in which modern advances have changed our

understanding of genetic processes.

LO7: Discuss the rapid growth of the field of epigenetics.

LO8: Describe 3 classic examples of research on behavioral development, and how

each illustrates gene–experience interaction.

LO9: It is important to distinguish between the development of individuals and the

development of individual differences. Explain.

LO10: Explain heritability estimates and how they are commonly misinterpreted.

LO11: Describe 2 ways that twin studies can be used to study the interaction of

genes and experience (i.e., nature and nurture).



There is a tendency to think in simple

dichotomies when explaining behavior.

Is it physiological or psychological?

Is it inherited or is it learned?

Both questions are common, yet misguided.

From Dichotomies to

Interactions



Cartesian dualism: Descartes argued that the

universe consists of two elements.

Physical matter

Human mind (soul, self, or spirit)

Cartesian dualism viewed the mind and brain

as separate entities.

Is It Physiological or

Psychological?



Problem 1: Brain damage has an impact on

psychological functioning.

Example: Oliver Sacks’s Case Study of a

Man with Asomatognosia Deficiency in awareness of parts of one’s

own body

Result of damage to the right parietal lobe

Problems of Traditional

Dichotomies: Mind–Brain Dualism



FIGURE 2.1 Asomatognosia typically

involves damage to the right parietal

lobe.



Is It Inherited or Is It Learned?

The “Nature–Nurture” Issue

Watson, a behaviorist, believed that all

behavior is the product of learning (nurture).

Ethology, the study of animal behavior in the

wild, focuses on instinctive (nature)

behaviors.



Problem 2: Chimps show psychological (i.e.,

“human”) abilities—for an example, see

Gallup’s research on chimp self-awareness

Chimps spontaneously groom themselves in

mirror.

Chimps examine and touch the red marks on

their own faces after seeing their reflections in a

mirror.


Dichotomies: Mind–Brain Dualism



Many factors other than genetics (nature) or learning

(nurture) have an impact on behavior.

“Nurture” now encompasses learning and

environment.

While it is generally accepted that behavior is a

product of nature and nurture, many still ask how

much is determined by each—but genetic and

experiential factors do not merely combine in an

additive fashion. Interactionism


Dichotomies: Nature or Nurture



FIGURE 2.3 A schematic

illustration of the way in which

many biopsychologists think

about the biology of behavior.





While Darwin was not the first to propose that species evolve, he was the first to compile supporting evidence (and to suggest ways in which evolution works).

Darwin presented 3 kinds of evidence.

Darwin argued that evolution occurs through natural selection.

Human Evolution



Darwin’s Evidence

Fossil evidence of evolution

Structural similarities among living species suggest common ancestors.

Impact of selective breeding

Direct Observation of Evolution in Progress: Grant (1991)

Finches of the Galapagos islands changed dramatically after a single season of drought.

Human Evolution: Evidence

for Evolution



FIGURE 2.4 Four kinds of evidence

supporting the theory that species

evolve.



Evolution and Behavior

Just as physical features contribute to “fitness,” so do behaviors.

Some are obvious—the ability to find food, avoid predation, etc.

Some are less obvious—social dominance and courtship displays.



Course of Human Evolution

Evolution of Vertebrates

Chordates have dorsal nerve cords.

Vertebrates are chordates with spinal bones.

Evolution of Amphibians

Bony fishes leave the water briefly.

Advantages include fresh water and new food sources.



FIGURE 2.6 A recently discovered

fossil of a missing evolutionary

link is shown on the right, and a

reconstruction of the creature is

shown on the left. It had scales,

teeth, and gills like a fish and

primitive wrist and finger bones

similar to those of land animals.




(Con’t) Evolution of Reptiles

Lay shell-covered eggs; covered by dry scales

Can live far from water

Evolution of Mammals

Develop mammary glands to nurture young

Eventually no longer lay eggs; raise young in mother’s body

Humans emerge from the order primates.



Emergence of Humankind Humans belong to family hominids, genus Homo.

The first homo species emerged from Australopethicus2 million years ago.

Homo sapiens emerged 200,000 years ago.


(Con’t)



FIGURE 2.9 A taxonomy of

the human species.



FIGURE 2.10 The remarkably

complete skull of a 3-year-old

Australopithecus girl; the fossil is

3.3 million years old.



FIGURE 2.12

Vertebrate evolution.



Thinking about Human

Evolution (Con’t)

Evolution does not proceed in a single line.

Humans have only been around for a brief

period of time.

Rapid evolutionary changes do occur.

Fewer than 1 percent of all known species

are still in existence.




Evolution (Con’t)

Evolution does not necessarily result in perfect design.

Not all existing behaviors or structures are adaptive.

Spandrels: incidental nonadaptive byproducts

(such as the human belly button)




Evolution (Con’t)

Not all existing adaptive characteristics

evolved to perform their current functions.

Exaptations: evolved to do one thing, but now

do something else (such as bird wings)

Similarities among species do not

necessarily mean that the species have

common origins.




Evolution (Con’t) Homologous structures: similar structures

due to a common evolutionary origin

Analogous structures: similar structures without a common origin

Convergent evolution: the evolution of similar solutions to the same environmental demands by unrelated species



Evolution of the Human Brain

There is no relationship between brain size

and intelligence.

Brain size is generally correlated with body

size.

It is more informative to look at the relative

sizes of different brain regions.



FIGURE 2.13 The brains of

animals of different evolutionary

ages—cerebrums are shown in

yellow; brain stems are shown in

purple.



Evolution of the Human Brain

(Con’t) The human brain has increased in size

during evolution.

Most of the increase in size has occurred in the cerebrum.

Increased convolutions in the cerebrum have served to increase the volume of the cerebral cortex.



Evolutionary Psychology:

Mate Bonding

Most species mate promiscuously.

Most mammals form polygynous mating

bonds.

Humans generally form monogamous bonds.

May be adaptive in allowing more attention to

survival of children



Thinking about Evolutionary

Psychology Current aspects of mate bonding in humans

appear to be predicted by evolutionary

theory. Examples:

Men tend to value indications of fertility.

Women tend to value power and earning capacity.

Physical attractiveness predicts which women bond

with men of high status.

Mate attraction strategies: for women, physical

attraction; for men, displaying power and resources

Men are more likely than women to commit adultery. Copyright © 2014 Pearson Education, Inc.


Fundamental Genetics

Dichotomous traits: occur in one form or the

other, never in combination

True-breeding lines: interbred members

always produce offspring with the same trait.

Mendel studied dichotomous traits in true-

breeding lines of pea plants.



Mendel’s Experiments

Mendel crossed a line bred true for brown

seeds with one bred true for white.

First-generation offspring all had brown

seeds.

When the first generation were bred, the

result was ¾ brown and ¼ white seeds.



Mendel’s Experiments (Con’t)

True-Breeding Lines

White (ww)

Brown (BB)

Brown was the dominant trait, appearing in all

of the first-generation offspring (Bw).




Phenotype: observable traits

Genotype: traits present in the genes

If the dominant trait is present in the

genotype (Bw), it will be observed in the

phenotype (brown seeds).



FIGURE 2.15 How Mendel’s

theory accounts for the results of

his experiment on the inheritance

of seed color in pea plants.




• Each inherited factor is a gene.

• Two genes that control the same trait are called alleles.

• Homozygous: 2 identical alleles (BB, ww)

• Heterozygous: 2 different alleles (Bw)



Chromosomes: Reproduction

and Recombination

• Genes are located on chromosomes in

the nucleus of each cell.

• Humans have 23 pairs of chromosomes,

with an allele on each chromosome.

• Meiosis: a process of cell division that

yields cells with just 23 chromosomes




and Recombination (Con’t)• Gametes, egg cells and sperm cells, are

produced by meiosis.

• When egg and sperm combine to form a fertilized egg (zygote), 23 pairs of chromosomes are again present.

• Mitosis: a form of cell division that yields daughter cells that have 23 pairs of chromosomes




and Recombination (Con’t)

• Meiosis leads to diversity as the 23 pairs of chromosomes are randomly sorted into the 2 gametes produced.

• Linkage: the tendency of traits encoded on the same chromosome to be inherited together

• Crossing over: increases diversity; “shuffles the genetic deck”



Chromosomes are DNA molecules: double strands

of nucleotide bases wrapped around each other.

A nucleotide on strand 1 always pairs with a

particular nucleotide on strand 2.

To replicate, the strands unwind; each

nucleotide attracts its complementary base,

making two DNA molecules identical to the

original.

Chromosomes: Structure and

Replication



FIGURE 2.18 DNA replication. As

the two strands of the original

DNA molecule unwind, the

nucleotide bases on each strand

attract free-floating

complementary bases. Once the

unwinding is complete, two DNA

molecules, each identical to the

first, will have been created.



Sex Chromosomes and

Sex-Linked Traits

Sex chromosomes, X and Y, look different

and carry different genes. Female = XX

Male = XY

Sex-linked traits are influenced by genes on the sex chromosomes.

Dominant traits on the X chromosome will be seen more commonly in females—recessive ones in males.



Genetic Code and Gene

Expression

Mechanism of Gene Expression

Strand of DNA unravels

Messenger RNA (mRNA) synthesized from DNA

(transcription)

The mRNA leaves the nucleus and attaches to a

ribosome in the cell’s cytoplasm.

Ribosome synthesizes protein according to 3-base

sequences (codons) of mRNA (translation).



Genetic Code and Gene

Expression (Con’t) Regulation of Gene Expression

Enhancers: stretches of DNA that determine

whether particular structural genes initiate the

synthesis of proteins, and at what rate

Transcription factors: proteins that bind to DNA and

influence the extent to which genes are expressed

Epigenetics: the pattern of actual gene expression,

vs. the genes possessed, is most important.

Patterns of gene expression appear to be heritable.



FIGURE 2.19 Gene

expression. Transcription of

a section of DNA into a

complementary strand of

messenger RNA is followed

by the translation of the

messenger RNA strand into

a protein.



Copyright © 2014 Pearson Education, Inc. All

rights reserved.

FIGURE 2.21 Two epigenetic

mechanisms.

Histone remodeling

involves modifications to a

histone protein (around

which DNA is coiled) and

can either decrease or

increase gene expression.

DNA methylation involves

the attachment of a

methyl group to DNA and

tends to reduce the

expression of adjacent

genes.

Mitochondrial DNA

Mitochondrial DNA

Mitochondria are the energy-generating

structures found in the cytoplasm of all cells.

Mitochondria have their own DNA.



Mitochondrial DNA

Mitochondrial DNA

Research interest in mitochondrial DNA

• Mitochondrial DNA may be responsible for some

• disorders.

• The constant rate of mitochondrial DNA mutation has

• been used as an evolutionary clock to determine,

• for instance, that hominids evolved in Africa and

• spread around the world.



Modern Genetics

Modern Genetics

The Human Genome Project mapped the 3 billion

base sequences of human DNA, as well as

those of some other species.



Modern Genetics (Con’t)

Humans were found to have only about 25,000 genes,

leading to new discoveries.

• Only a small proportion of chromosome segments

contain protein-coding genes.

• Vast regions of DNA were once thought to be

inactive evolutionary remnants. However, they are

now thought to influence the structural genes.

• “Active nongene DNA”



Modern Genetics (Con’t)

• MicroRNA appears to have an expanded role in

gene expression, beyond carrying information from

the nucleus.

• Some genes produce more than one protein.

• Alternative splicing of messenger RNA provides a

mechanism

• Evidence for expression of only one allele of a gene

(monoallelic expression) has accumulated in the

past few years.



Behavioral Development: The

Interaction of Genetic Factors

and Experience

Three Influential Studies

Selective breeding of “maze-bright” and “maze-dull” rats

Phenylketonuria: a single-gene metabolic disorder

Development of birdsong



of maze-bright and maze-dull

strains of rats by Tryon (1934).

(Data from Cooper, R.M., &

Zubek, J.P. (1958). Effects of

enriched and restricted early

environments on the learning

ability of bright and dull rats.

Canadian Journal of

Psychology, 12, 159-164.)



FIGURE 2.23 Maze-dull rats

did not make significantly

more errors than maze-bright

rats when both groups were

reared in an enriched

environment. (Adapted from

Cooper & Zubek, 1958.)



Phenylketonura: A Single-

Gene Metabolic Disorder

Due to Single Mutant Recessive Gene

A special diet during a critical period of

development lessens mental retardation.

An Example of Interaction between Genetics

and Environment



Development of Birdsong

Young males must hear their species’ songs

during the critical period, or they develop

abnormal songs.

Young male canaries have left-side

neurological dominance for song, like human

left dominance for speech.

Adult male canaries grow new neurons each

spring: an early discovery of adult

neurogenesis.



The Genetics of Human

Psychological Differences The Minnesota study of twins reared apart

showed that identical twins are more similar

to each other than fraternal twins on all

psychological dimensions.

Example: Correlations of the IQs of identical twins

whether raised together or apart is larger than

that of fraternal twins raised together.



Individual Differences (Con’t)

Heritability Estimates

Refer to populations, not to individuals

Cannot be generalized to populations from

dissimilar environments

Multiplier effect: genetically similar individuals seek

out similar environments

Turkheimer et al. (2003) found that the heritability of

IQ was near 0 in impoverished twins and near 1

(maximum) in affluent twins.



powerpoint presentation for biopsychology…drrobingoins.com/assets/chapter_2_ppt.pdf · for...

Documents