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