How organisms interact

Predator/Prey interactions  Predation - The act of one organism killing another for food.  Ex. Lions eating zebras

Defense  Defense Camouflage Hibernation Migration Mimicricy

Plant Defense  Secondary compounds – Means of defense for plants  Ex. Mustard plants (produce mustard oil, toxic to many insects), Poison ivy, Tobacco

Coevolution  The back-and-forth evolutionary adjustments between interacting members of an ecosystem.  Ex. Newt and Garter snake Newts poison - only 1/13 of the poison found in the newt is enough to kill a human

Symbiosis  Symbiosis – Two or more species living together in a close, long term association Parasitic Mutualistic Commensalism

Parasitism  One organism feeds on and usually lives on or in another organism. (parasites do not usually kill their prey)  Ex. Roundworms, fleas, mosquitoes. Ticks.

Mutualism  A symbiotic relationship in which both species benefit.  Ex. Ants and aphids, Yuccas and Yucca moths

Mutualism: Yuccas and Yucca moths

Commensalism  A symbiotic relationship in which one species benefits and the other is neither harmed nor helped.  Ex. Clown fish and sea anemone

Competition  Remember - resources are limited Organisms lessen competition by finding a niche  Niche – How the organism lives (includes what they eat, where they live, etc.), not to be confused with habitat Ex. Diet, reproduction, time of activity

Competition  Fundamental niche – The entire range of resource opportunities an organism is able to occupy.  Realized niche – the set of resources the population actually uses (due to competition)