ECOL1000 Exam 1

Population ecology

how population sizes change over time and space

Uncontrolled exponential pop growth represented by

J-curve

Limited exponential pop growth represented by

S-curve

At limit

No growth

Above limit

Negative growth/declination

Below limit

Positive growth

Density-dependent factors

Impacts on population related to their size. Ex. predation, disease

Density-independent factors

Impact on population UNRELATED to pop size. Ex. natural disasters

Demographic Transition Model

5 stages; 1 - high births and deaths; 2 - high births, declining deaths; 3 - declining births and deaths; 4 - low/fluctuating births, low deaths; 5 - low births, high deaths

Population pyramid growth

Triangle

Population pyramid stagnation

Rectangle

Population pyramid decline

Inverse triangle

Population momentum

Tendency for a pop to keep growing after fertility rates drop to replacement rate. Aka demographic inertia

Ecological footprint

Amount of resources needed to support each person; how we live influences how much we need and of what

Demographic-economic paradox

Higher income, education and development = lower birth rates