Chapter 57.txt

The overall transfer of energy from one trophic level to the next, expressed as the ratio of consumer production to producer production.

The amount of energy captured by the primary producers in a community.

• The rate at which energy captured by photosynthesis is incorporated into the bodies of primary producers bodies through growth and reproduction.
• Species richness is highest when productivity is average
• High productivity leads to Competitive Exclusion

• The rate at which the primary producers in a community turn solar energy into stored chemical energy via photosynthesis.
• GPP=NPP+R

• The amount of primary producer biomass made available for consumption by heterotrophs. 
• Not all energy created by primary producers is mad available for consumption by primary consumers; some of it is lost during cellular respiration and growth; thus
• NPP = GPP − R
• where R is energy lost by respiration

A group of organisms united by obtaining their energy from the same part of the food web of a biological community.

The progression over successively lower trophic levels of the indirect effects of a predator.

• An organism that builds structures that alter existing habitats or create new habitats.
• Ex: Beavers, plants, kelp, coral

A result of competition between species for a limiting resource in which one species completely eliminates the other.

• An evolutionary phenomenon in which species that compete for the same resources within the same territory tend to diverge in morphology and/or behavior.
• Competition leads to resource partitioning which produces a divergence in strucuture, which leads to...
• Sympatric Speciation

A type of interaction between species in which one participant benefits while the other is unaffected.

• Symbiosis: Mutualism, Commensalism, Parasitism
• Competition
• Predation
• Mimicry: Batesian, Mullerian
• Camouflage
• Warning Coloration
• Chemical Defenses
• Coevolution

• Competition for resources: food, shelter, light, mates, space etc.
• Mating
• Socializing
• Safety

• Species that have a dominant influence on the composition of a community.
• Effect of the species on the community is disproportionate to the abundance
• Sometimes these organisms can cause a trophic cascade
• Ex: Elephant, Sea Stars, California Sea Otter, Carribean Lobster

a nontoxic species (the mimic) resembles a toxic species (the model) and benefits from the avoidance behavior learned by the predator in response to the toxic model species; ex: hoverfly, wasp

• a number of aposematic species converge on a common color pattern; all benefit from providing a stronger recognition signal to predators
• two agressive species benefit from their resemblence to one another because predators of both organisms avoid both organisms

• Noxious Secretions
• Spray
• Defense against herbivory: plants: unpleasant taste or harmful effects

• two organisms interact so closely that each has an effect on each others evolution over time
• Ex: bats and moths: both have developed their own sonars to detect, avoid each other
• Ex: Catepillar, wasp and plant
• Ex: orchids and bees

• Mimicry
• Coloration: Warning, camouflage, mimicry
• Chemical Defenses
• Coevolution
• Trophic Cascade
• Keystone Species

• Alpha diversity: diversity within a single community or habitat
• Beta diversity: between-habitat diversity, a measure of the change in species composition from one community or habitat to another
• Gamma diversity: the regional diversity found over a range of communities or habitats in a geographic region

A theory proposing that the number of species on an island (or in another geographically defined and isolated area) represents a balance, or equilibrium, between the rate at which species immigrate to the island and the rate at which resident species go extinct.

• In agriculture, a large-scale planting of a single species of domesticated crop plant
• Ex: What if all our forests were composed entirely of Hemlock trees when the hemlock beetle was introduced to the US?

The gradual, sequential series of changes in the species composition of a community following a disturbance.

Succession that begins in an area initially devoid of life, such as on recently exposed glacial till or lava flows. (Contrast with secondary succession.)

Succession after a disturbance that did not eliminate all the organisms originally living on the site. (Contrast with primary succession.)

The final stage of succession; a community that is capable of perpetuating itself under local climatic and soil conditions and persists for a relatively long time

• species that are good dispersers
• species with high intrinsic rates of reproduction
• simple food webs
• nutrients that are available primarily in abiotic sources

• Succession in detritus-based communities, which differs from other types of succession in taking place without the participation of plants
• Ex: Succesion of insects on human corpse

• the climax community depends on periodic disturbance in order to persist
• Ex: periodic forest fires