Ch. 41 Species Interactions Flashcards
Relationships between species in a community
Interspecific interactions
And assemblage of populations of various species living close enough for potential interaction
A biological community
Occurs when species compete for resources that limits their growth or survival
Interspecific competition
Local elimination of a competing species
Competitive exclusion
A specific set of biotic and abiotic resources used by an organism
Ecological niche
Differentiation of ecological niches enabling similar species to coexist in a community
Resource partitioning
The niche potentially occupied by that species
Fundamental niche
The niche actually occupied by that species
Realized niche
The tendency for characteristics to be more divergent in sympatric populations of two species than in allopatric populations of the same two species
Character displacement
Positive negative interaction refers to an interaction in which one species the predator kills and eats the other the prey
Predation
Makes prey difficult to spot
Cryptic coloration or camouflage
Animals with effective chemical defenses often exhibit bright warning coloration
Aposematic coloration
A palatable or harmless species mimics and unpalatable or harmful model
Batesian mimicry
Two or more unpalatable species resemble each other
Müllerian mimicry
Positive negative interaction refers to an interaction in which an herbivore eats parts of a plant or algae
Herbivory
A relationship where two or more species live in direct and intimate contact with one another
Symbiosis
Positive negative interaction one organism the parasite derives nourishment from another organism it’s host which is harmed in the process
Parasitism
Parasites that live within the body of their host
Endoparasites
Parasites that live on the external surface of a host
Ectoparasites
Positive negative interaction an interspecific interactions that benefits both species
Mutualism
Positive neutral interaction one species benefits and the other is neither harmed nor helped
Commensalism
Positive positive or positive neutral interaction in which one species has positive effects on another species without direct and intimate contact
Facilitation
What are two fundamental features of community structure
Species diversity and feeding relationships
Variety of organisms that make up the community
Species diversity
What two components consist in species diversity
Species richness and relative abundance
The number of different species in the community
Species richness
The portion each species represents of all individuals in the community
Relative abundance
Uses the Shannon diversity index
Comparing diversity
Communities with higher diversity are
More productive and more stable in their productivity
Produce biomass more consistently than single species plots
Better able to withstand in recover from environmental stresses
More resistant to invasive species organisms that become established outside their native range
Total mass of all individuals of a population
Biomass
Link trophic levels from producers to top carnivores
Food chains
A branching food chain with complex trophic interactions
A food web
Most abundant or have the highest biomass
Dominant species
Dominant species are most competitive in
Exploiting resources
Exert strong control on a community by their ecological roles or niches
Not necessarily abundant in the community
Keystone species
Cause physical changes in the environment that affect community structure
foundation species
Ecosystem engineers
Organization that poses a Uni directional influence from lower to higher trophic levels
Bottom Up model
Describe communities as constantly changing after being buffeted by disturbances
Non-equilibrium model
In the event that changes a community removes organisms from it and alters resource availability
Disturbance
Suggests that moderate levels of disturbance can foster greater diversity than either high or low levels of disturbance
Intermediate disturbance hypothesis
What does high level of disturbance exclude
Slow-growing species
What does low levels of disturbance exclude
Less competitive species than the dominant species
The sequence of community in ecosystem changes after disturbance
Ecological succession
Occurs where no soil exists when succession begins
Primary succession
Begins in an area where soil remains after a disturbance
Secondary succession
The result of changes induced by the vegetation itself
Succession
Two key factors that affect a communities species diversity
Latitude and area
Two key factors in equatorial-polar gradients of species richness
Evolutionary history and climate
Two main climatic factors correlated with biodiversity
Sunlight and precipitation
Can have dramatic effects on community structure when they are introduced into new habitats
PathogenS
Transferred from other animals to humans
Zoonotic pathogens
Transfers the pathogens
Vector
