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84 Cards in this Set

  • Front
  • Back
The study of relationships between organisms and their natural environment, living and nonliving
Keystone Species
A species whose activities have a significant role in determining community structure
Dominant Species
Species who is greatest in number
A discrete event in time that disrupts an ecosystem, community, or population, changing substrates and resource availability
--causes succession--
Primary Succession
Vegetational development starting on a new site never before colonized by life
Secondary Succession
Development of vegetation after a disturbance
Net Primary Productivity (NPP
Rate of energy fixation or storage per unit time after respiration

Net 1° Productivity (NPP) = Gross 1° Productivity (GPP) - Respiration by autotrophs (R)
Gross Primary Productivity
The total rate of photosynthesis (energy assimilated by autotrophs)
How do you measure photosynthesis, respiration, and net primary productivity by phytoplankton in aquatic ecosystem?
Light bottle (O₂ produced by photosynthesis and consumed by phytoplankton) - Dark bottle (sample is only O₂ consumed in respiration) = O₂ produced by photosynthesis (gross primary productivity)
A measure of the different kinds of organisms within a certain region
Local Extinction
What is local extinction called?
Acid precipitation
Biological Oxygen Demand
SLOSS debate
Single Large or Several Small Reserves?
Chemical substance released by an an imal that influences behavior of others of the same species
Cultural Eutrophication
Accelerated nutrient enrichment of aquatic ecosystems by a heavy influx of pollutants that causes major shifts in plant and animal life
A group of individuals of the same species living in the same place at the same time
Principle of Allocation
Energy allocated for or expended on one purpose is not available for other functions
- aka: energy is finite (neither created nor destroyed)
Transmissble changes in the structure of a gene or chromosome
Change in gene frequency through time resulting from natural selection and producing cumulative changes in characteristics of a population
Genetic Drift
Random fluctuation in allele frequency over time, due to chance alone without any influence by natural selection; important in small populations
Carrying Capacity
(K) - maximal sustainable population size
situation in which two dissimilar organisms live together in close association
any interaction that is mutually detrimental to both participants, occurring between species that share limited resources
relationship between two species in which both benefit
Relationship between two species in which one benefits and the other is harmed
Relationship between two species in which one benefits and the other is not effected
What is a relationship called when one organism is harmed and the other is not effected?
Relationship between to organisms in which one is harmed and the other is not effected
What is a relationship called when one organism is harmed and the other is not effected?
Major regional ecological community of plants and animals; usually corresponds to plant ecologists' and European ecologists' classification of plant formations and life zones
Genetic contribution by an individual's descendants to future generations
(6 types)
The movement of an individual in space - usually means away from each other

1. density-dependent
2. human-assisted
3. landscape corridors
4. metapopulations
5. within populations
6. seeds
Seed Dispersal
Most seeds fall near the parent, and density falls of with distance

* heavier seeds have shorter dispersal range than light, wind-carried seeds

* some species depend on active carriers to disperse
Seed Bank
The store of seeds within the terrestrial ecosystem
Seed Rain
Method of seed dispersal of light seeds
Eutrophic Climate
Freshwater bodies which are rich in plant nutrients and therefore highly productive.
Oligotrophic Climate
Describes water or soil that has poor nutrient content (does not sustain life well)
1st Law of Thermodynamics
Energy can be neither created nor destroyed
2nd Law of Thermodynamics
no transfer of energy is 100% efficient
Intermediate Disturbance Hypothesis
species diversity is greatest in those habitats experiencing a moderate amount of disturbance, allowing the coexistence of early and late successional species
Natural Selection
differential reproduction and survival of individuals that results in elimination of maladaptive traits from a population
Joint evolution of two or more species that have a close ecological relationship -- through reciprocal selective pressures, the evolution of one species in the relationship is partially dependent on the evolution of the other
R-Selected Species
* variable population size (usually below K)
* high reproductive rate
* single reproductive event (semelparous)
* weak competitive ability
* good dispersal ability
* live in disturbed habitats
K-Selected Species
* slow development
* low reproductive rate
* repeated reproduction
* long life
* strong competitive ability
* population size fairly constant
* live in undisturbed habitat
coloration resembles warning colors of toxic species (ex: butterflies)
Hutchensonian Niche
The niche is multidimensional (hypervolume) - species may overlap in some niche dimensions, but never all
Mullerian Mimicry
Unpalatable species share similar coloration - predator only has to be exposed to one and knows not to eat the others
What are two types of mimicry?
Batesian (unharmful copies coloration of harmful) and Mullerian (many harmful share coloration, pred therefore only eats one and then stops)
Exponential Growth
(r) = instantaneous rate of population growth. Expressed as a proportional in crease per unit of time

dN/dt = rN(t)
Logistic Growth
Model incorporates the concept of carrying capacity -- results in a decrease in the rate of pop growth as pop size approaches K
When does exponential growth happen?
populations inhabtiting favorable environments at low population densities -- such as during the process of colonization and establishment in new environments
Invasive Species
a nonnative species that successfully colonizes a disturbed area or empty niche, spreads, and outcompetes associated native speces
coloration of organisms that makes them resemble or blend into their habitat or background
Aposematic Coloration
coloration of an organism that makes them stand out as dangerous (warning signals)
Stratification in Lakes and Turnover
Division of an aquatic or terrestrial community into distinguishable layers on the basis of temperature, moisture, light, vegetative structure -- creates zones for different plant an animal types
Liebig's Law of the Minimum
Growth is controlled not by the total of resources available, but by the scarcest (limiting) resource.
Producing an overabundance of seed/fruit, enough to satiate the fruit predator and still have some left to grow - usually occurs every 3 years
Nutrient Cycling
Pathway of an element or nutrient through the ecosystem, from assimilation by organisms to release by decomposition
Hardy-Weinberg Equilibrium
The proposition that genotypic ratios resulting from random mating remain unchanged from one generation to another, provided natural selection, genetic drift, and mutation are absent

If in Equilibrium = No Evolution
Integrated Pest Management
Fundamental Niche
In theory, what (variables) could an organism thrive under
Realized Niche
In actuality this range is smaller - subset of fundamental niche
Theory of Island Biogeography
The number of species established on an island represents a dynamic equilibrium between the immigration of new colonizing species and the extinction of previously established ones.
Target Effect
Greater Immigration on Larger Islands (big target, more organisms will land there)
Rescue Effect
Decreased Extinction on Closer Islands (constantly new inflow replaces lost organisms)
Reproductive Isolating Mechanisms
1. Fertilization Barriers (pre-zygotic) -- physical barriers ex: enzymes to penetrate ovum

2. Hybrid Barriers (post-zygotic) -- usually hybrids are sponaneously aborted, or they are infertile
1. Allopatric/geographic -- two populations are isolated from each other for long periods

2. Sympatric speciation -- occurs as a result of disruptive selection
Handicap Hypothesis
The idea that females prefer a trait (ex: big peacock feathers) because it is a handicap to the male, therefore if they are able to survive they must have good genes
Rain Shadow
A dry region on the leeward side of a mountain range resulting from a reduction in rainfall
Gause's Law
No two species can coexist indefinitely on the same limiting resource
Major Causes of Decline in Global Biodiversity
1. Habitat loss
2. Habitat change
3. Competition from exotic species
4. Predation by exotic species
5. Overharvesting
6. Poisoning
Conditions of Competitive Exclusion Principle
1. time has been sufficient to allow exclusion
2. the environment is temporally constant
3. the environment has no spatial variation
4. growth is limited by one resource
5. rarer species are not disproportionately favored in terms of survivorship, reproduction, or growth
6. species have the opportunity to compete
7. there is no immigration
Factors that Effect Species Richness
Causes Decreas:
* latitude
* altitude

Causes increase:
* area
* environmental variability

* time since disturbance
* nutrients
* predation rate
* productivity
Kyoto Protocol
Countries commit to reduce CO2 emission & other greenhouse gases by 5.2% compared to 1990
Tragedy of the Commons
Social Trap -- conflict over resources between individual interests and the common good (individuals always behave selfishly to maintain fitness
Behavior by an individual that increases the fitness of another individual while decreasing the fitness of the actor
Logistic Growth Formula
dN/dt = rN(1-N/K)
Exponential Growth Formula
dN/dt = rN(t)
Hardy-Weinberg Formula
p + q = 1

p2 + 2pq + q2 = 1
Photosynthesis Formula
6 CO2 + 12 H2O → C6H12O6 + 6 O2 + 6 H2O

carbon dioxide + water + light energy → glucose + oxygen + water
Cellular Respiration Formula
C6H12O6 + 602 → 6CO2 + 6H2O + heat
Lincoln-Peterson (Mark-Recapture) Formula
~N = nM/R

estimation of pop size = # captured first * # captured second / # of captured second that were marked from first