1. Ec Ecological Hierarchy OrganismSpeciesPopulationcommunity

2. 1.2 Biotic Interactions I. ______commensalism_______: a relationship that benefits one species but does not harm the other Example: Barnacles live on Wales II. _______Mutualism_______: A relationship that benefits both species Example:bee-flower; human intestine-bacteria http://www.youtube.com/watch?v=z3bWqlPLpMg&feature=BFa&list= PL7866C558BE801106&lf=mh_lolz III._______Parasitism_______: A relationship that benefits one species and harm the other. Example : flee- animals; tapeworms-animal http://www.youtube.com/watch?v=KrWk2g- IMkE&feature=BFa&list=PL7866C558BE801106&lf=mh_lol z Symbiosis= refer to the interaction between members of two different species that live together in a close association

3. All of the physical, chemical, and biological interactions require for a species to survive, grow and reproduce are part of the organisms' niche  where he sleeps and where he eats Competition is a harmful interaction between two or more organisms that can occur when organisms compete for food Niche: Competitition:

4. Predation (Figure 47): 1. predator-prey interaction are part of the food web. Predator eats prey 2. prey use camouflage and other adaptation that keep them from being eaten. 3. predators and prey are directly influenced by each other.  When predators numbers are low, the prey numbers go up. When they gets too high, the predators numbers increase