Ecology: Communitiy

Commensalism

________: one member derives a benefit while the other is not benefited or harmed.

Ectoparasites

________: parasites that live on the external surface of a host.

Defensive mutualism

________: animal defends a plant or herbivore.

Grass pink orchid

________ produces no nectar, but it mimics the nectar- producing rose pogonia and is therefore still visited by bees.

Food chains

________ link trophic levels from producers to top carnivores.

Conjugation

________: unites results of oxidation with another molecule to create inactive and readily excreted product.

Trophic structure

________: the feeding relationships between organisms in a community.

Plants

________ cheat seed- dispersal agent out of meal with barbs or hooks on seeds.

Phoresy

________: one organism uses another for transportation.

Cryptic coloration

________, or camouflage, makes prey difficult to spot.

Endoparasites

________: parasites that live within the body of their host.

Predation

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

Mutualisms

________ are beneficial- but optimal needs of each party can be different.

Interspecific interactions

________: relationships between species in a community.

Sugar maples

________ have a major impact on shading and soil nutrient availability in eastern North America 🡪affects the distribution of other plant species.

Parasitism

________ (+-/interaction): one organism, the parasite, derives nourishment from another organism, its host, which is harmed in the process (does not usually kill it outright)

Animals

________ also have morphological and physiological defense adaptations.

Relative abundance

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

Secondary metabolites

________: not part of primary.

Resource partitioning

________: differentiation of ecological niches, enabling similar species to coexist in a community.

similar species

Ecologically ________ can coexist in a community if there are one or more significant differences in their niches.

Donor

________- controlled system: prey supply is determined by factors other than predation, such as food supply.

Flower inhabiting mites

________ use hummingbird nostrils.

Facultative mutualism

________: the species cant live apart.

Facilitation

________ (+ /+ or 0 /+): an interaction where one species can have positive effects on another species without direct and intimate contact.

Herbivores

________ can overcome plant defenses.

Keystone species

________: exert strong control on a community by their ecological roles, or niches.

Inhibition

________: species replacement is prevented by previous colonists.

Tolerance

________: species replacement is unaffected by previous colonists.

Fungus

________ produces gongylidia as ant food.

Dispersive mutualism

________: one species receives food in exchange for helping the flower spread their pollen.

Generalist herbivores

________: can feed on many plant species.

Specialist herbivores

________: restricted to one or two host plants.

Species diversity

________: the variety of organisms that make up the community.

Obligatory mutualism

________: neither species can live alone.

Oxidation

________: catalysis of secondary metabolite to corresponding alcohol by mixed- function oxidases (MFOs)

Displays of intimidation

________: deceive predator about ease of eating prey.

Importance of predation

________ depends on whether its a donor- controlled system or a predator- controlled system.

Ants

________ chew up leaves to feed to fungus they care for.

Trophic mutualism

________: both species utilize a common resource.

Dominant species

________ are most competitive in exploiting resources vs they are most successful at avoiding predators.

Behavioral defenses

________ include hiding, fleeing, forming herds or schools, self- defense, and alarm calls.

Invasive species

________, typically introduced to a new environment by humans, often lack predators or disease.

Ecological niche

________: the total of a species use of biotic and abiotic resources.

Interspecific interactions

________ can affect the survival and reproduction of each species,

Herbivory

________ can be lethal to small species.

Facilitation

________: species replacement is assisted by previous colonists.

Mutualism

________: close associations between species in which both species benefit.

Community

an assemblage of populations of various species living close enough for potential interaction

Ecological niche

the total of a species use of biotic and abiotic resources

Resource partitioning

differentiation of ecological niches, enabling similar species to coexist in a community

Fundamental niche

the niche potentially occupied by that species

Realized niche

the niche actually occupied by that species

Interspecific interactions

relationships between species in a community

Intraspecific competition

competition between individuals of the same species

Interspecific competition

competition between individuals of different species

Exploitation competition

organisms compete indirectly through the consumption of a limited resource

Interference competition

individuals interact directly with one another by physical force or intimidation

ex

Bombardier beetle ejects hot spray

Displays of intimidation

deceive predator about ease of eating prey

ex

Porcupine fish inflates itself

Donor-controlled system

prey supply is determined by factors other than predation, such as food supply

Predator-controlled system

action of predator feeding reduces supply of prey

Generalist herbivores

can feed on many plant species

Specialist herbivores

restricted to one or two host plants

Secondary metabolites

not part of primary

Oxidation

catalysis of secondary metabolite to corresponding alcohol by mixed-function oxidases (MFOs)

Conjugation

unites results of oxidation with another molecule to create inactive and readily excreted product

Endoparasites

parasites that live within the body of their host

Ectoparasites

parasites that live on the external surface of a host

Mutualism

close associations between species in which both species benefit

Trophic mutualism

both species utilize a common resource

Example

Leaf-cutting ants and fungus

Defensive mutualism

animal defends a plant or herbivore

ex

Ants protect aphid, aphid secretes honeydew

Facultative mutualism

the species cant live apart

ex

Ants nesting in acacia trees defend the tree and trim away competing plants

Obligatory mutualism

neither species can live alone

Dispersive mutualism

one species receives food in exchange for helping the flower spread their pollen

Mutualisms are beneficial

but optimal needs of each party can be different

Commensalism

one member derives a benefit while the other is not benefited or harmed

ex

Epiphytes growing in trees do not harm the trees

ex

Cattle egrets benefit from cattle stirring up insects

Phoresy

one organism uses another for transportation

Facilitation (+/+ or 0/+)

an interaction where one species can have positive effects on another species without direct and intimate contact

Facilitation

species replacement is assisted by previous colonists

Inhibition

species replacement is prevented by previous colonists

Tolerance

species replacement is unaffected by previous colonists

Species diversity

the variety of organisms that make up the community

It has two components

species richness and relative abundance

Species richness

the total number of different species in the community

Relative abundance

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

Trophic structure

the feeding relationships between organisms in a community

Dominant species

the species that are most abundant or have the highest biomass

Keystone species

exert strong control on a community by their ecological roles, or niches

Ecological succession

the sequence of community and ecosystem changes after a disturbance

Primary succession

when succession begins; occurs where no soil exists

Secondary succession

begins in an area where soil remains