issues in human ecology

ecology

the study of how organisms interact with each other and their physical environments

human ecology

a discipline that deals with relationships between humans, human societies, and their natural, social, and created environments

social system

everything about people, their population, and the psychology and social organization that shape their behavior

feedback loops

changes in one part of a system cause ripple effects, whether it’s stabilizing (negative feedback) or worsening (positive feedback)

population

all members of the same species living in the same area

population size

number of total individuals

population density

number of individuals per unit area

dispersion

distribution of individuals within a given space

population growth

an increase in the number of people that reside in a country/state/county/city in a particular time

growth rate

(birth rate + immigration) - (death rate + emigration)

density dependent factors

factors related to population size

density independent factors

factors that control population, regardless of population size

exponential growth

rapid growth

logistic growth

rapid growth following by a leveling off around carrying capacity

carrying capacity

maximum number of individuals of a particular species that an environment can support

mark/recapture method

mark individuals sample population multiple times, + using math to estimate population size

sampling

go out + measure, usually must estimate

demography

study of human populations

developed countries

higher incomes, diverse economies

developing countries

lower income, simple agriculture-based economies

age structure

distribution of ages in a country

population histogram/age structure diagram

double-sided bar graph showing age + sex distribution of a population

fertility rate

the number of babies born each year per 1,000 women

doubling time

the time it takes for a population growing at a specific rate to double its size

rule of 70

way to calculate doubling time (DT)

demographic transition model

a model that shows effects of economic & social changes on population growth

pre-industrial societies

high per capita death rates offset by high per capita birth rates

transitional societies

per capita birth rates have remained high while per capita death rates have fallen

post-industrial societies

low per capita death rates and per capita birth rates

female infanticide

intentional killing of newborn female infants

family planning

educational & clinical services to help couples choose the number of children