Ch. 1 & 3 Test Flashcards
Tragedy of the Commons; Examples
Unregulated exploitation of public resources leads to depletion and damage; Resource users are motivated by self interest.
Examples: Soil, air, and water
Solutions to the tragedy of the commons?
Private ownership
Voluntary organization to enforce responsible use
Governmental regulations
Ecological Footprint
The environmental impact of a person or population;
The area of biologically productive land + water
The Scientific Method
It tests ideas; Observation Questions Hypothesis Prediction Test Results
Variable
A condition that can change.
Independent Variable
Can be manipulated
Dependent Variable
Depends on the independent variable
Control
An unmanipulated point of comparison
Sustainability
To live within our planet’s means so the Earth and its resources can sustain us and all life for the future.
conserving resources
Sustainability involves…….
Developing long-term solutions
Keeping fully functioning ecosystems
Natural Selection Vs Artificial Selection
Natural Selection describes Traits that enhance survival and reproduction are passed on more frequently to future generations than those that do not.
While Artificial Selection is:
The process of selection conducted under human direction
Producing the great variety of dog breeds and food crops
3 Types of Natural Selection
Directional selection = drives a feature in one direction
Stabilizing selection = favors intermediate traits; Preserving the status quo
Disruptive selection = traits diverge in two or more directions
Allopatric speciation Vs Sympatric speciation
Allopatric speciation is species formation due to physical separation of populations
While Sympatric speciation is species form from populations that become reproductively isolated within the same area
Fossil record
The cumulative body of fossils worldwide;
Which show that;
Life has existed on Earth for at least 3.5 billion years
Earlier types of organisms evolved into later ones
The number of species has increased over time
Niche
An organism’s use of resources along with its functional role in a community:
Habitat use,
food selection,
role in energy and nutrient flow,
interactions with other individuals
Specialists Vs Generalist
Specialists have narrow niches and specific needs
While Generalist are species with broad niches
Survivorship Curves
The likelihood of death varies with age
Exponential growth
>A population increases by a fixed percent >Graphed as a J-shaped curve >cannot be sustained indefinitely >Small population >Low competition >Ideal conditions
Density-dependent factors Vs Density-independent factors
Density-dependent factors are limiting factors whose influence is affected by population density
While Density-Independent factors are limiting factors whose influence is not affected by population density
K-selected species Vs R-selected species
K Species have; long gestation periods and few offspring
>low biotic potential
>Stabilize at or near carrying capacity
>Good competitors
While R species which reproduce quickly have:
>A high biotic potential
>Little parental care, populations fluctuate greatly