Population Basics
This term refers to a group of individuals of the same species living in an area.
What is a population?
The phase of population growth where growth is slow because few individuals are reproducing.
What is the lag phase?
All factors that prevent unlimited population growth are called these.
What are limiting factors?
Organisms that produce many offspring with little or no parental care.
What are r-strategists?
The main reason human population growth increased rapidly in recent history.
What is a decrease in death rates due to medicine and technology?
The number of individuals added to a population through reproduction.
What is natality?
This phase shows rapid population increase as many individuals reproduce.
What is the exponential growth phase?
This term describes all limiting factors acting together on a population.
What is environmental resistance?
Organisms that produce few offspring and provide parental care.
What are K-strategists?
This formula is used to describe environmental impact.
What is I = P × A × T?
This population characteristic shows how many individuals are in each age group.
What is age distribution?
The maximum sustainable population an environment can support.
What is carrying capacity?
Limiting factors that come from outside the population, such as floods or droughts.
What are extrinsic limiting factors?
This type of organism often experiences population crashes instead of stabilizing.
What are r-strategists?
The “A” in I = P × A × T stands for this.
What is affluence?
This curve shows the proportion of individuals that survive to different ages.
What is a survivorship curve?
Population growth slows during this phase as birth and death rates become similar.
What is the deceleration phase?
These limiting factors become stronger as population density increases.
What are density-dependent limiting factors?
Humans are considered this type of reproductive strategist.
What are K-strategists?
This concept measures the land area needed to support a population’s resource use and waste.
What is an ecological footprint?
A population will grow only when this rate is higher than the death rate.
What is the birth rate (or natality)?
Carrying capacity can change because these conditions are not constant over time.
What are environmental conditions or limiting factors?
Overcrowding causing stress behaviors that reduce birth rates is an example of this type of limiting factor.
What is an intrinsic limiting factor?
These population patterns are common in northern ecosystems and repeat over time.
What are population cycles?
Population growth in the U.S. continues largely because of this factor.
What is immigration?