Carrying Capacity & Growth Models
This type of population growth occurs when there are no limits on resources, resulting in a J-shaped curve.
What is exponential growth ?
The panda is a prime example of this type of species, which relies on a narrow diet and specific habitat requirements.
What is a specialist species?
As of July 1, 2024, this country (long predicted to become #1) is NOW the most populated country in the world, with a population of 1,409,128,296 and a population growth rate of 0.8%.
What is India?
This stage of the demographic transition model experiences rapid population growth due to declining death rates?
What is Stage 2 ?
This is the formula for calculating the growth rate of a population.
What is (births - deaths) / total population × 100 ?
This is the maximum population size that an environment can sustain over a long period of time.
What is a carrying capacity ?
These species are characterized by having many offspring and little parental care.
What are r-selected species?
The Total Fertility Rate (TFR) needed for replacement-level fertility is approximately this in developed countries.
What is 2.1?
A country whose Age Structure Diagram looks like an inverted pyramid would most likely be in this stage of the DTM.
What is Stage 5 ?
What is the doubling time (in years) for a population growing at a rate of 3% per year?
What is approximately 23.3 years? (70 ÷ 3 = 23.3)
Food availability, disease, and predation are all examples of this.
What are density-dependent limiting factors ?
This type of survivorship curve is often associated with K-selected species.
What is Type I?
Continued population growth even after fertility rates decline, due to a large percentage of young individuals is called this.
What is population momentum?
This stage of the DTM is referred to as "high Stationary", as high birth and death rates offset resulting in a stable or "stationary" population growth rate.
What is Stage 1 ?
A town with 10,000 residents experiences 200 births, 100 deaths, 50 immigrants, and 25 emigrants in a year. This is the annual growth rate.
What is 1.25%?
[ (200 + 50) - (100 +25) / 10,000 ] x 100 = 1.25%
This is a term for the sudden decline in a population following an overshoot of the carrying capacity, often caused by resource depletion or environmental degradation.
What is die-off ?
A mosquito lives for 2 – 3 weeks. A female mosquito lays between 100 – 300 eggs about 10 times during her life. The population declines at a relatively even rate throughout their lifespan.
This is the survivorship type AND reproductive strategy we associate with this example.
What is Type II survivorship and R-selected?
Countries with high TFR often also have high values of this.
What is high infant mortality?
(high child mortality)
In Stage 4 of the Demographic Transition Model, countries typically experience low birth rates, resulting in this type of population growth.
What is zero (or near-zero population) growth?
"Stable"
A town’s population increased from 80,000 to 92,000 in 4 years. This is the percent change in population over that time.
What is a 15% increase?
Calculation: 92,000 - 80,000 / 80,000 × 100 = 15%
When discussing predator-prey relationships, this predictable model is seen which shows cyclical population fluctuations among the two organisms.
What is boom-and-bust model (polynomial growth) ?
This is why K-selected species are more vulnerable to extinction compared to r-selected species.
They reproduce slowly and cannot adapt quickly to changes in environmental conditions.
Identify TWO factors that would decrease Total Fertility Rate (TFR).
1. Increased education for women
2. Women's roles in society (having jobs)
3. Laws (Government policies discouraging large families)
4. Access to family planning
5. Improved child survival rates
The transition from Stage 2 to Stage 3 in the Demographic Transition Model is often influenced by this key societal/cultural shift.
What is women entering the workforce?
You capture and mark 40 deer in a forest. Later, you recapture 20 deer and find that 8 are marked. Estimate the total deer population.
What is 100 deer? [(40 × 20) ÷ 8 = 100]