Biological CommunitiesBiological Communities

Community InteractionsCommunity Interactions

• Coevolution-Adjustments between Coevolution-Adjustments between members of an ecosystem members of an ecosystem

• Adaptations-Change that increases Adaptations-Change that increases chance of survivalchance of survival

• Symbiosis-Two or more species Symbiosis-Two or more species ““live live togethertogether””

Predation Predation

• Benefits one harms the other (+/-)Benefits one harms the other (+/-)

• One organism kills another for foodOne organism kills another for food

• Ex: Snake eating a mouseEx: Snake eating a mouse

ParasitismParasitism

• Benefits one harms Benefits one harms the other (+/-)the other (+/-)

• One organism feeds One organism feeds & usually lives on or & usually lives on or in another organism in another organism (don(don’’t typically kill the t typically kill the host)host)

• Ex: parasite on Ex: parasite on marine fish marine fish

Mutualism Mutualism

Benefits both (+/+)

Zebra & Bird Bee & Flower

Camouflage: Poor-will (left), lizard (right)Camouflage: Poor-will (left), lizard (right)

Aposematic (warning) coloration in a poisonous blue frogAposematic (warning) coloration in a poisonous blue frog

Deceptive coloration: moth with "eyeballs"Deceptive coloration: moth with "eyeballs"

MimicryMimicry

CommensalismCommensalism

Benefits one & the other is neither helped or harmed (+/0)

Clown fish & sea anemone

Crabs & sea anemone

CompetitionCompetition

• Benefits neither species (-/-)Benefits neither species (-/-)

• Two species directly competing for same resourceTwo species directly competing for same resource

• Niche: organismNiche: organism’’s s ““jobjob”” in an ecosystem in an ecosystem– What does it do? Eat? What does it do? Eat? – Where does it live?Where does it live?

• Ways of dealing with competitionWays of dealing with competition– Different niches: use different resourcesDifferent niches: use different resources

Biomes: Communities found Biomes: Communities found over large areasover large areas

Climate: Temperature & PrecipitationClimate: Temperature & Precipitation

Rain Forest: highest biodiversity Ex: Puerto Rain Forest: highest biodiversity Ex: Puerto RicoRico

Savannah: grasses & scattered Savannah: grasses & scattered trees, fire Ex: East Africatrees, fire Ex: East Africa

Coniferous Forest (Taiga): cold & Coniferous Forest (Taiga): cold & wet Ex: Canada wet Ex: Canada

Tundra: permafrost, very cold, Tundra: permafrost, very cold, high wind, low rainfall, short high wind, low rainfall, short vegetation Ex: Alaskavegetation Ex: Alaska

Desert: <30 cm rainfall/ Desert: <30 cm rainfall/ yr yr

Temperate Grassland: (Prairies) Temperate Grassland: (Prairies) moderate climates, rich soilmoderate climates, rich soil

Temperate Deciduous Forest: Mild Temperate Deciduous Forest: Mild climates, eastern USclimates, eastern US