Download Biological Communities

Biological Communities
Community Interactions
• Coevolution-Adjustments between
members of an ecosystem
• Adaptations-Change that increases chance
of survival
• Symbiosis-Two or more species “live
together”
Predation
• Benefits one harms the other (+/-)
• One organism kills another for food
• Ex: Snake eating a mouse
Parasitism
• Benefits one harms
•
the other (+/-)
One organism feeds &
usually lives on or in
another organism
(don’t typically kill
the host)
• Ex: parasite on
marine fish
Mutualism
Benefits both (+/+)
Zebra & Bird
Bee & Flower
Camouflage: Poor-will (left), lizard (right)
Aposematic (warning) coloration in a poisonous blue frog
Deceptive coloration: moth with "eyeballs"
Mimicry
Commensalism
Benefits one & the other is neither helped or
harmed (+/0)
Clown fish & sea anemone
Crabs & sea anemone
Competition
• Benefits neither species (-/-)
• Two species directly competing for same resource
• Niche: organism’s “job” in an ecosystem
– What does it do? Eat?
– Where does it live?
• Ways of dealing with competition
– Different niches: use different resources
Biomes: Communities found
over large areas
Climate: Temperature & Precipitation
Rain Forest: highest biodiversity Ex: Puerto Rico
Savannah: grasses & scattered trees,
fire Ex: East Africa
Coniferous Forest (Taiga): cold & wet
Ex: Canada
Tundra: permafrost, very cold,
high wind, low rainfall, short
vegetation Ex: Alaska
Desert: <30 cm rainfall/ yr
Temperate Grassland: (Prairies) moderate
climates, rich soil
Temperate Deciduous Forest: Mild climates,
eastern US