evolutionary Psychology Exam 2

Darwin's 'hostile forces of nature'

Climate, weather, food shortages, toxins, diseases, parasites, predators, other people.

Evolutionary standpoint of being dead

You can no longer ensure your own reproductive success, nor that of your offspring or kin.

Savanna Hypothesis

Humans prefer landscapes that offer refuge and resources (R and R), neither fully closed nor fully open.

FEED theory

Food preferences evolved to favor calorically dense foods because they were adaptive in the past.

FIND: Is it food?: Use cues such as color, texture, and odor. We gravitate towards red foods due to ripeness.

- EVALUATE: Is it nutritious and good to eat? : Our sense of smell is enhanced when we are hungry. We prefer processed foods, such as those that have been cut, ground, soaked, and cooked. Pre-ancestral food processing caused our teeth to become less sharp and our digestive systems to become less complex.

- EXCLUDE: Is it dangerous? Use smell and taste, and to a lesser extent, vision. Food neophobia is the fear of unfamiliar foods.

- DECIDE: Should I eat it? Watch what others around us eat

-FIND: Is it food?: Use cues such as color, texture, and odor. We gravitate towards red foods due to ripeness.

• EVALUATE: Is it nutritious and good to eat? : Our sense of smell is enhanced when we are hungry. We prefer processed foods, such as those that have been cut, ground, soaked, and cooked. Pre-ancestral food processing caused our teeth to become less sharp and our digestive systems to become less complex.

• EXCLUDE: Is it dangerous? Use smell and taste, and to a lesser extent, vision. Food neophobia is the fear of unfamiliar foods.

• DECIDE: Should I eat it? Watch what others around us eat.

Spices and evolutionary psychology

Many spices help preserve food or protect against illness.

Spices inhibit bacteria, which is why we like spices. It makes food safer to eat and is antibacterial. Hotter climates use more spices as they counteract a heavy amount of bacterial growth in hot environments. This is also the case for wetter environments as well. Mostly used in places like India, Vietnam, the Philippines, Kenya, and Mexico.

Behavioral Immune System

An evolved system of emotions, cognitions, and behaviors that promote detection and avoidance of disease.- Aversion to and avoidance of things that can make you sick

" first line of defense"

explains why some people have food preferences after being disgusted

Disgust and morality

Disgust evolved for pathogen avoidance but was co-opted for moral judgments (exaptation).

link between the Behavioral immune system and prejudice

Prejudice toward groups stereotypically associated with illness

Ex: people with birthmarks, acne, or wrinkles we think are "sick" not because they are unsafe, but because of the behavioral immune system trying to protect us from threats.

Why do concerns about pathogens increase prejudice towards groups perceived to be foreign?

Unfamiliar groups historically posed a higher risk of introducing novel diseases. Often carried pathogens to which people did not develop immunity

Ex: Aztecs, Spanish, smallpox

BIS: Individualism vs collectivism at the national level

• At the national level, countries with historically high pathogen prevalence (lots of infectious disease threats) tend to have more collectivist cultures, while countries with low pathogen prevalence tend to be more individualistic.

• High-pathogen environments (collectivism)

• Low-pathogen environments (individualism)

• correlated with more introversion and more conservative sexual norms.

Pathogen prevalence shapes culture: more disease = more collectivism, less disease = more individualism.

Taste aversion

-Aversion to novel taste paired with nausea. One-trial learning.

• illustrates the intersection between evolution and learning

Preparedness theory

An evolutionary explanation for the rapid acquisition, high resistance to extinction, and uneven distribution of specific phobias, suggesting that humans are biologically predisposed to learn fears towards objects and situations that posed a survival threat to our ancestors.

Pregnancy Sickness Embryo-Protection Hypothesis

Nausea and food aversions during weeks 4-14 of pregnancy protect the fetus from toxins, lowering miscarriage rates.

• women are most repulsed by bitter food and meat.

• increased prejudice

Common phobias and why

During ancestral times, these were the things we were most afraid of and posed a threat to our survival.

• animals, heights, public speaking, water/drowning, enclosed spaces, germs/illness, public speaking, death

treatment- systematic desensitation= = exposure therapy

What is fear?

Threat-based emotional adaptation that motivates avoidance or confrontation of dangers.

• psychological: increases epinephrine, glucose, and breathing rate

• behavioral: the 3 F's = flight, fight, or freeze ( avoid predation/detection)

-cognative: attention narrows and focuses on threat. The sense of hearing is heightened in the dark.

Fear vs anxiety

Fear = attention narrows
anxiety = attention expands

anxiety = attention expands

What are the positives of fear?

-can improve memory, especially for threats

-causes people to make less risky, more conservative decisions to not risk safety

Smoke Detector Principle in fear

It is better to have false alarms than miss a real threat, because the cost of missing danger is higher.

• Fear can make things appear more threatening due to ancestors being a lot more vulnerable

overgeneralzation

Fear and anxiety readily generalized to non-dangrous stimuli that are similar in appearance or category to dangerous stimuli.

• error on the side of caution

Fear and learning

• preparedness to learn certain fears is efficient (not all fears are equal)

• ancestral dangers learned more easily than modern, novel dangers ( spiders vs cars)

• difficult to condition fear to irrelevant stimuli ( flowers)

fear and dangerous people

• characteristics historically associated with interpersonal danger

• men: the capability of being more violent and strong

• anger: intent ( antagonism)

• outgroup: lack of restraint( few bacterial interactions, different social norms)

• People detect certain emotions as dangerous, such as anger.

race and fear

• People categorize others by race, but this is not an adaptation.

• Race is used heuristically by some people as a cue to group membership

Red Queen Hypothesis

Sexual reproduction mixes genes to increase resistance to rapidly evolving pathogens, creating an evolutionary arms race between pathogens and hosts.

What are the costs of sexual reproduction?

-inefficient at transmitting genes

• 50% of your genes are passed to the next generation

• requires two organisms, unlike asexual

• cost of finding and attracting a partner

Benefits of sexual reproduction

Sexual reproduction produces a greater chance of variation within a species than asexual reproduction does.

This variation improves the chances that a species will adapt to its environment and survive. and survive new variations of pathogens.

Parental investment theory - females

Females have larger, costlier gametes and higher obligatory investment (pregnancy, resources).

Parental investment theory - males

less choosy.

obligatory investment: one act of intercourse

needs: be chosen as a mate, maximize the number of mating opportunities

The difference between male and female gametes

male sperm ( in more abundance)

Female egg ( larger, less mobile)

• Female gametes are more reproductive " valuable" and require a larger energetic investment.

• difference in levels of minimum obligatory parental investment

The cost of male and female mating

• male: opportunity costs of parenting effort

• female: bad mating choices

Sexual Strategies Theory

A theory that maintains that women and men have evolved distinct mating strategies because they faced different adaptive problems over the course of human history. The strategies used by each sex maximize the probability of passing along their genes to future generations.

• long term vs short term

-large sex difference in chimpanzees and small sex differences in gibbons. We are in the middle of both dimorphic states.

Clark & Hatfield (1989) study

Men were far more likely than women to agree to casual sex offers from strangers.

Coolidge effect

Males show renewed sexual interest when introduced to new receptive partners. Desire for sexual variety among males. Driven by testosterone to maximize sexual opportunities.

What does sexual strategies theory suggest about the lower investing sex?

The lower investing sex possesses adaptations that help them be chosen as a mate and maximize the number of mating opportunities.

What is an example of intersexual selection/risk-taking in sexual strategies theory?

Risk taking in peacocks.

What is an example of intrasexual competition in sexual strategies theory?

Rams butting heads.

What adaptations does the higher investing sex possess according to sexual strategies theory?

Greater choosiness.

What drives much of mate selection in sexual strategies theory?

Female choice.

parental investment theory

a theory that stresses the evolutionary basis of many aspects of parental behavior, including the extensive investment parents make in their offspring

• desire for sexual variety

What if males invest more than females?

• males choosier

• females are larger, more competitive, and aggressive

Strategic Pluralism

Variation in sexual strategies within each sex depending on traits and environment; e.g., attractive men may be more promiscuous.

Some women may be willing to sacrifice commitment to mate with highly attractive men

Life History Theory

Childhood environment (safe vs. unpredictable) shapes mating strategy: slow strategy vs. fast strategy.

The role of sex drive/sexual desire

related to testosterone in both sexes

related to estrogen in women

50% of people under 26 are thinking about sex within the last 5 minutes