Chapter 54 Flashcards
Aposematic Coloration
The bright warning coloration of many animals with effective physical/chemical defenses
Batesian Mimicry
A type of mimicry in which a harmless species looks like a species that is poisonous or otherwise harmful to predators
Biomanipulation
An approach that applies the top-down model of community organization to alter ecosystem characteristics
Biomass
The total mass of organic matter comprising a group of organisms in a particular habitat
Bottom-up Model
A model of community organization in which mineral nutrients influence community organization by controlling plant or phytoplankton numbers, which in turn control predator numbers
Character Displacement
The tendency for characteristics to be more divergent in sympatric populations of two species than in allopatric populations of the same two species
Commensalism
A symbiotic relationship in which one organism benefits but the other is near helped nor harmed
Competitive Exculsion
The concept that when populations of two similar species compete for the same resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population
Community
All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction
Cryptic Coloration
Camouflage that makes a potential prey difficult to spot against its background
Disturbance
A natural of human-caused event that changes a biological community and usually removes organisms from it. Disturbances, such as fires and storms, play a pivotal role in structuring many communities
Ecological Niche
The sum of a species’ use of the biotic and abiotic resources in its environment
Dominant Species
A species with substantially higher abundance or biomass than other species in a community. Dominant species exert a powerful control over the occurrence and distribution of other species
Ecological Succession
Transition in the species composition of a community following a disturbance; establishment of a community in an area virtually barren of life
Ecosystem Engineer
An organism that influences community structure by causing physical changes in the environment
Ectoparasite
A parasite that feeds on the external surface of a host
Endoparasite
A parasite that lives within a host
Energetic Hypothesis
The concept that the length of a food chain is limited by the inefficiency of energy transfer along the chain
Facilitation
An interaction in which one species has a positive effect on the survival and reproduction of another species without the intimate association of a symbiosis
Evapotranspiration
The total evaporation of water from an ecosystem, including water transpired by plants and evaporated from a landscape, usually measured in millimeters and estimated for a year
Food Webs
The interconnected feeding relationships in an ecosystem
Herbivory
An interaction in which an organism eats part of a plant or alga
Host
The larger participant in a symbiotic relationship, often providing a home and food source for the smaller symbiont
Intermediate Disturbance Hypothesis
The concept that moderate levels of disturbance can foster greater species diversity than low or high levels of disturbance
Interspecific Interactions
A relationship between individuals of two or more species in a community
Interspecific Competition
Competition for resources between individuals of two or more species when resources are in short supply
Invasive Species
A species, often introduced by humans, that takes hold outside its native range
Keystone Species
A species that is not necessarily abundant in a community yet exerts strong control on community structure by the nature of its ecological role or niche
Mullerian Mimicry
Reciprocal mimicry by two unpalatable species
Mutualism
A symbiotic relationship in which both participants benefit
Nonequilibrium Model
A model that maintains that communities change constantly after being buffeted by disturbances
Parasitism
A symbiotic relationship in which one organism, the parasite, benefits at the expense of another, the host, by living either within or on the host
Parasite
An organism that feeds on the cell contents, tissues, or body fluids of another species (the host) while in or on the host organism. parasites harm but usually do not kill their host
Primary Succession
A type of ecological succession that occurs in an area where there were originally no organisms present and where soil has not yet formed
Pathogens
An organism or virus that causes disease
Predation
An interaction between species in which one species, the predator, eats the other, the prey
Relative Abundance
The proportional abundance of different species in a community
Resource Partitioning
The division of environmental resources by coexisting species such that the niche of each species differs by one or more significant factors from the niches of all coexisting species
Shannon Diversity
An index of community diversity symbolized by H
Secondary Succession
A type of succession that occurs where an existing community has been cleared by some disturbance that leaves the soil or substrate intact
Species-area Curve
The biodiversity pattern that shows that the larger the geographic area of a community is, the more species it has
Species Diversity
The number and relative abundance of species in a biological commmunity
Species Richness
The number of species in a biological community
Symbiosis
An ecological relationship between organisms of two different species that live together in direct and intimate contact
Top-Down Model
A model of community organization in which predation influences community organization by controlling herbivore numbers, which in turn control plant of phytoplankton numbers, which in turn control nutrient levels; also called the trophic cascade model
Trophic Structure
The different feeding relationships in an ecosystem, which determine the route of energy flow and the pattern of chemical cycling
Vector
An organism that transmits pathogens from one host to another
