Community Ecology, Biodiversity, and Disruptions

Symbiosis

________: when 2 or more species live in direct contact with one another.

Human activity

________ is the strongest disturbance to an ecosystem.

Parasitism

________: (+-)/when one organism (parasite) derives nourishment from another (host)

Commensalism

________: (+ /0) when one organism benefits and the other is neither harmed nor benefited.

Mutualism

________: (+ /+) when both organisms benefit from the relationship.

Human disturbance

________ have lead to a significant increase in the number of endangered species.

Habitat

________: a place or part of an ecosystem occupied by an organism.

Herbivory

________: +-/relationship where one organism eats part of a plant or alga.

unintentional introduction

The intentional or ________ of an invasive species can allow the species to exploit a new niche that is free of predators or competitors.

Predation

________: +-/relationship where one species (predator) kills and eats the other species (prey)

Global change

________: alterations to climate, atmospheric chemistry, and ecological systems that reduce the capacity of Earth to sustain life.

Latitude

________: species are more diverse in tropics than at the poles due to climate.

Relative abundance

________: the proportion each species represents of all the individuals in the community.

Disturbance

________: an event that changes a community by removing organisms from it or altering resource availability.

Habitat loss

________: single greatest threat to biodiversity.

Facilitation

________: (+ /+ or 0 /+) when one species has a positive effect on the survival and reproduction of another without intimate association of symbiosis.

Keystone species

________, producers, and essential abiotic and biotic factors contribute to maintaining the diversity of the ecosystem.

Pathogens

________: disease causing organisms and viruses.

Mullerian mimicry

________: two or more bad- tasting species resemble each other.

Ecological succession

________: the gradual process by which the species composition of a community changes and develops over time after a disturbance.

Bees

________ are a keystone species because they serve as pollinators.

Coral reefs

________ serve as a keystone species because many other organisms rely upon it as a source of food and protection.

Biogeographical factors

________: large scale factors that contribute to a range of diversity observed.

Niche partitioning

________: natural selection drives competing species into different patterns of resource use, or different niches.

Batesian mimicry

________: harmless species mimics a harmful one.

Primary succession

________: a series of changes on an entirely new (previously lifeless) habitat that has not been colonized.

Interspecific interactions

________: interactions of individuals from one species with individuals of another species.

Pathogens

________ have the most effect on new habitats or ecosystems with less biodiversity.

Community

a group of populations of different species living closely and capable of interacting

Habitat

a place or part of an ecosystem occupied by an organism

Ecological niche

the role and position a species has in its environment

Fundamental niche

the niche potentially occupied by the species if there were no limiting factors (predators, competitors, etc)

Realized niche

the portion of the fundamental niche the species actually occupies

Interspecific interactions

interactions of individuals from one species with individuals of another species

Competitive exclusion principle

two species competing for the same resource cannot coexist permanently

Niche partitioning

natural selection drives competing species into different patterns of resource use, or different niches

Cryptic coloration

camouflage

Batesian mimicry

harmless species mimics a harmful one

Mullerian mimicry

two or more bad-tasting species resemble each other

Symbiosis

when 2 or more species live in direct contact with one another

Parasitism

(+/-) when one organism (parasite) derives nourishment from another (host)

Mutualism

(+/+) when both organisms benefit from the relationship

Commensalism

(+/0) when one organism benefits and the other is neither harmed nor benefited

Facilitation

(+/+ or 0/+) when one species has a positive effect on the survival and reproduction of another without intimate association of symbiosis

Species diversity (biodiversity)

the variety of different organisms within a community

Species richness

the number of different species

Relative abundance

the proportion each species represents of all the individuals in the community

Example

a ship bringing produce from another country may have insects in the crates holding the produce

Keystone species

not usually abundant, but other species in an ecosystem rely on them because of their important ecological niches

Example

coral

Example

honey bees

Disturbance

an event that changes a community by removing organisms from it or altering resource availability

Ecological succession

the gradual process by which the species composition of a community changes and develops over time after a disturbance

Primary succession

a series of changes on an entirely new (previously lifeless) habitat that has not been colonized

Secondary succession

a series of changes that clears an existing community, but leaves the soil intact

Habitat loss

single greatest threat to biodiversity

Overharvesting

organisms are harvested faster than their population can rebound

Global change

alterations to climate, atmospheric chemistry, and ecological systems that reduce the capacity of Earth to sustain life

Biogeographical factors

large scale factors that contribute to a range of diversity observed

Latitude

species are more diverse in tropics than at the poles due to climate

Area

larger areas are more diverse because they offer greater diversity of habitats

Pathogens

disease causing organisms and viruses