Demographics
High-Yield Summary
- Demographics = statistical study of populations. Age: 'Graying of America' (aging boomers), fastest-growing cohort = 85+, ageism = age-based prejudice. Gender = social construct (behavior/roles); sex = biological (XY/XX).
- Race = social construct based on phenotype (always visibly on display); ethnicity = social construct based on culture/language/nationality/religion (a matter of choice to display). Symbolic ethnicity = ethnic symbols matter even when ethnicity isn't central to daily life.
- Sexual orientation measured via the Kinsey Scale (0 = exclusive hetero, 6 = exclusive homo). Intersectionality (Crenshaw, 1989): overlapping demographic factors (race, gender, immigration status) compound disadvantage beyond the sum of each alone.
- Fertility rate = avg. children/woman/lifetime (U.S. below replacement level 2.1 since 2007, ~1.6 now). Mortality rate = deaths/population/time. Crude rate = unadjusted total-population rate. Migration: immigration (in) vs. emigration (out), driven by push/pull factors.
- Demographic transition (4 stages, tracked as birth-rate/death-rate pairs): Stage 1 high-high → Stage 2 high birth, dropping death (fastest growth) → Stage 3 dropping birth, low death → Stage 4 low-low. Malthusian theory (Malthus, 1798): population growth can outpace food supply.
- Social movements: proactive (promote change — women's rights, civil rights) vs. reactive (resist change — antiglobalization, counterculture), often driven by relative deprivation. Globalization = global economic integration (pros: food access; cons: unemployment, pollution, unrest). Urbanization: ghettos (minority concentration) vs. slums (extreme density + poor housing/sanitation).
Key Terms
- Ageism
- Prejudice based on a person's age, seen across all ages.
- Gender vs. sex
- Gender = social construct (roles/traits); sex = biological (chromosomes).
- Racial formation theory
- Racial identity is fluid, dependent on concurrent political/economic/social factors.
- Intersectionality
- Crenshaw (1989): overlapping demographic disadvantages compound rather than simply add.
- Population pyramid
- Histogram of population size by age cohort, visualizing age-structure shifts.
- Push/pull factors
- Push = negative attributes driving emigration from an origin; pull = positive attributes drawing immigration to a destination.
- Malthusian catastrophe
- Scenario where population growth outpaces food supply, causing mass starvation.
- Ghettos vs. slums
- Ghettos = minority concentration areas; slums = extreme case, dense population + low-quality housing/sanitation.
Demographic Transition — 4 Stages
- 1Stage 1 (preindustrial): birth rate high, death rate high
- 2Stage 2: death rate drops (healthcare/nutrition/sanitation improve), birth rate stays high — fastest population growth
- 3Stage 3: birth rate drops (contraception, women's rights, industrial shift), death rate stays low
- 4Stage 4 (industrialized): birth rate low, death rate low
Common MCAT Trap
- Sex = biological classification; gender = social construct — a vignette about chromosomes/gonads tests sex, one about roles/identity tests gender.
- Race sorts by phenotype (always visible); ethnicity sorts by culture (a matter of choice to display) — not the same axis, and a person can hold one race but multiple ethnic identities.
- Don't assume any drop in birth or death rate signals the same demographic transition stage — track the pair: dropping death rate + still-high birth rate = Stage 2, not Stage 1 or 3.
- Proactive movements promote change; reactive movements resist it — sort by direction, not by which side seems more 'active.'
Quick Recall
A country shows a rapidly dropping death rate but a birth rate that remains high. Which demographic transition stage?
A low-income Black patient experiences worse health outcomes than either race or income alone would predict. What concept explains the compounding effect?
Irish-Americans who don't practice Irish culture daily still strongly identify with and celebrate St. Patrick's Day. What's this called?
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