ENS 112

Population Growth

A change in the size of a population over time resulting from births, deaths, immigration and emigration

Urbanization

The increasing concentration of people in urban areas as populations shift from rural to urban regions

Cultural Carrying Capacity

The maximum number of people who can live in reasonable freedom and comfort indefinitely without reducing Earth’s ability to support future generations

Total Fertility Rate (TFR)

The average number of children born to a woman during her reproductive years

Replacement-level fertility rate

the average number of children a couple must have to replace themselves in a population

Demographic Transition

A process through which countries move from high birth and death rates to lower birth and death rates as they industrialize and develop economically

Theory

Explains why something happens

Law

describes what happens

Negative Feedback Loop

A negative feedback loop occurs when a change triggers a response that reduces or counteracts the change

Ecosystem structure

physical components that make up the ecosystem

Ecosystem function

biological, chemical, and physical processes that happen because of the ecosystems structure

Ecosystem services

benefits humans receive from the ecosystems structure and functions

Sustainability

capacity of the earth’s natural systems to survive, flourish, or adapt to changing environmental conditions indefinitely

Biomimicry

the scientific effort to understand, mimic, and catalog, the ways nature has sustained life on Earth for 3.8 billion years

Range of tolerance

the range of physical and chemical conditions under which a population can survive and reproduce

Parasitism

A species interaction in which one organism benefits at the expense of another species usually causing it harm without killing it

Decomposers

break down dead organisms and wasters into simpler nutrients (chemically break it down)

Detritivores

feed directly on dead organic material and wastes (consume dead material)

Species Diversity

the number and realtive abundance of different species in an ecosystem

Ecosystem Diversity

The variety of ecosystems,habitats, and ecological communities

Functional diversity

The variety of ecological roles organisms perform

Health biodiversity

increases ecosystem stability, resilience, and sustainability

Biodiversity loss

can reduce ecosystem services and make ecosystems more vulnerable to disturbance

Biome

a large geographic region characterized by its climate vegetation and dominant forms of life

Specialists Species

Can only survive under a narrow set of conditions

Generalist Species

Can survive in many places and eat many different foods

Indicator Species

Tells us whether environmental conditions are healthy or unhealthy

Keystone species

has a much larger impact on the ecosystem than it population size would suggest not necessarily the most abundant species however if removed the ecosystem changes dramatically

Ecological Niche

An ecological niche describes how a species interacts with its environment and other organisms 

Invasive Species

An invasive species is a nonnative species that spreads rapidly and causes ecological economic or environmental harm in its introduced range

Biological evolution

The change in the genetic characteristics of a population over a successive generation

Natural selection

The process by which individuals with advantageous inherited traits survive and reproduce more successfully than individuals without those traits