Transcript Document
Communities BBECPO Great Blue Heron Supplies energy to Lives in Becomes Chinook Salmon Smolts Competes for space with Isopods California Mussel Acorn Barnacle Wrinkled Whelk (Snail) Snails Dungeness Crab Eelgrass Polychaete Worms Zooplankton Phytoplankton Detritus Diatoms Great Blue Heron Supplies energy to Lives in Becomes Chinook Salmon Smolts Competes for space with Isopods California Mussel Acorn Barnacle Wrinkled Whelk (Snail) Snails Dungeness Crab Eelgrass Polychaete Worms Zooplankton Phytoplankton Detritus Diatoms Great Blue Heron Supplies energy to Lives in Becomes Chinook Salmon Smolts Competes for space with Isopods California Mussel Acorn Barnacle Wrinkled Whelk (Snail) Snails Dungeness Crab Eelgrass Polychaete Worms Zooplankton Phytoplankton Detritus Diatoms Communities • One “community” refers to all populations (i.e., various species) living together, interacting with each other, in a shared space. Community Interactions • Predator-Prey – One gets eaten, one does the eating – Example: Pac-man frog, that sits and waits for mice and other small frogs (“sit and wait predator”) • Competition – Shared space leads to competing for resources. Think siblings! – Both species tend to suffer a little • Symbiosis (sym = “together”; bio = “life”) – Mutualism – Commensalism – Parasitism Mutualism An interaction where both symbiotic organisms benefit. +/+ Commensalism An interaction where one organism benefits and the other is unaffected. +/0 +/- Parasitism An interaction where one organism benefits (the parasite) and the other is at a disadvantage (the host). Food Chains and Trophic Levels • The word trophic derives from the Greek trophē referring to “food” or “feeding”. • The trophic level of an organism is the position it occupies in a food chain. • A food chain represents a succession of organisms that eat another organism and are, in turn, eaten themselves. • Explain what is being shown here. Where might humans fit? Food Webs Connect back to… • Estuary Ecosystem or The Fish and the Forest • List one member for each trophic level: – Primary Producer: – Primary Consumer: – Secondary Consumer: – Tertiary Consumer: Your Task • Read textbook excerpt, Energy Supply Limits the Length of Food Chains – Approximately how much energy (percentagewise) is used or lost as heat as we move up the food chain? – Why are food chains limited to only 4-5 trophic levels? What would an appropriate title be, incorporating the terms energy and production? Food Chains vs. Food Webs Compare and Contrast Ecological communities with higher biodiversity form more complex trophic paths. The greater the biodiversity, the more stable the ecosystem. Why do you think this is the case?