A Darwinian View of Life

what is the difference between evolutionism and cultural psychology?

Evolutionism → focus on similarity between humans and animals (searching for commonalities)

• Cultural psychology: differences between different groups of people (the opposite of evolution)

what are the 4 observations that drive the theory of evolution?

• Organisms vary in endless ways: size, speed, strength, visual/hearing abilities, digestive processes, wisdom, etc.

• Some of these characteristics are heritable—can be passed down from one generation to the next

• Availability of resources can never catch up with the rate of reproduction—competition for resources occur within and across species

• A heritable trait will become prevalent if this trait enhances the survival of an organism and its offspring

what is fitness?

refers to reproductive success (number of descendants) of an individual organism relative to the average reproductive success in the population

what is adaptation?

heritable trait that increases the fitness of an individual in a particular environment relative to individuals lacking the trait

• Heritable traits: biological traits, behaviours, motivation? Cognition?

what is a species?

a group whose members possess similar anatomical characteristics and are able to interbreed

what is a population?

a group of individuals of the same species living in the same place at the same time

what is speciation?

the evolution of new species

what is population genetics?

a field of science that combines Darwin’s and Mendel’s ideas by studying how populations change genetically over time (very similar to microevolution)

(re. Mendel is pea plant study guy (was the basis for the discovery of genes)

what is modern synthesis?

populations are the units of evolution

• Combines the idea of population genetics and natural selection to explain gradual changes in a populations

what is a theory?

explain how (mechanistic explanation) or why (functional explanation) something happens; or both how and why

• E.g., classical conditioning theory explains how a stimulus acquires the capacity to evoke a response that was originally evoked by another stimulus

what are the steps in a scientific investigation?

• Formulate a testable hypothesis

• Select the research method and design the study

• Collect the data

• Analyze the data and draw conclusions

• Report the findings

what are the features on an experimental design?

• The experimenter has control over the independent variables

• There is at least one control group

• Random assignment of subjects into different groups (for between-subjects design)

• Hypothesis about causation

what is a feature of a non-experimental design?

Correlational

what is a quasi-experimental design?

(quasi = similar to); e.g., has a causal hypothesis, has some form of manipulation, but with no random assignment of subjects to groups (male/female → you cannot randomly assign this)

what is a correlational design? (non-experimental)

one group, no treatment. you just measure and analyze the measurements

what is an ex post facto (after the fact) design? (non-experimental)

one group, no direct manipulation (naturally occurring events), then you measure after the event and analyze

what is an ex post facto, two natural groups, no treatments design? (non-experimental)

two groups, selection criterion (quasi-experimental — are chosen based off a specific trait, e.g., male/female). no treatment, you simply measure and compare the two groups

what is a single group, posttest-only design? (demonstration) (non-experimental)

one group, one treatment. measure and analyze

what is a quasi-experimental, two natural-group design? (non-experimental)

two groups (are not random. made based on a specific trait). same treatment, same measurement. compare two groups

what is a two-random-sample design? (experimental)

two groups (experimental and control. random). differing treatment based on group. same measurement. compare the groups

what is a repeated measures design (within subjects, single group) (experimental)

one group. measure before treatment (control). treatment. measure after treatment (experimental). analyze differences

what is descent with modification?

• Is a phrase that Darwin used to mean that the species existing today have descended from other, preexisting species and those species are modified, or change, through time

• Even though the mechanisms of natural selection can be tested and supported experimentally, we cannot conclude that species have evolved by natural selection

what is proof for species changing through time?

• Most species have gone extinct

• Fossil (extinct) species frequently resemble living species found in the same area

• Traditional forms document change in traits through time

• Earth is ancient

• Vestigial traits are common

• Populations and species can be observed changing today

what is proof for species being related, not indepdent?

• Closely related species often live in the same geographic area

• Homologous traits are common and exist at three levels

  • Genetic (gene structure and genetic code)

  • Developmental (embryonic structures and processes)

  • Structural (morphological traits)

what are homologous traits?

related species have characteristics that have an underlying similarity yet function differently

what is a transitional form?

• Is a fossil species with traits that are intermediate between those of older and younger species

• E.g., land-dwelling mammals that had limbs evolved into ocean-dwelling mammals that had reduced limbs or no limbs

what is a vestigial trait?

• Is a reduced or incompletely developed structure that has no function or reduced function, but it is clearly similar to functioning organs or structures in closely related species

• E.g., coccyx (tailbone) in humans

• Are evidence that the characteristics of species have changed over time

what is genetic homology?

• If two species have very similar amino acid sequences, the identical parts must have been inherited from a common ancestor

• E.g., humans and rhesus monkeys

what is developmental homology?

Structures that appear early in development that are similar

what is structural homology?

Limbs with different functions have the same underlying structure

what is the position of Darwinism on the philosophical viewpoint spectrum?

in the middle of nature (materialism) and nurture (behaviourism)

what is the position of evolutionary psychology on the philosophical viewpoint spectrum?

in the middle of internal attribution (personality psychology) and external attribution (social and cultural psychology)

what are the two theoretical approaches to motivation?

evolutionary perspective (survival / biological and psychological needs)

humanistic perspective (self-actualization / need for acheivement)