1. Ecological Relationships How do biotic factors influence each other? http://www.cs.umbc.edu/courses/undergraduate/201/fall06/projects/p1/fox-rabbit.jpg http://www.univie.ac.at/zoologie/ecophys/crabsp-300dpi.jpg

2. Ecological Relationships Biodiversity = the number of species in an ecosystem http://www2.warwick.ac.uk/about/environment/faqs/biodiversity.jpg Importance: increases opportunity for natural selection without extinction Territory = space claimed by an individual organism Geographical Range = total area available to a species for its habitat Ecological Equilibrium = state of “balance” in an ecosystem

3. Ecological Relationships SPECIES – Organisms so close genetically, they can breed & get fertile offspring NICHE - Role of organism in the ecosystem (job) –Competitive Exclusion: Only 1 species can occupy a whole niche in an ecosystem at a time NICHE DIVERSITY – Number of niches in an ecosystem; often determined by abiotic factors A niche is the sum of all activities and relationships a species has while obtaining and using resources needed to survive and reproduce Abiotic = non-living

4. Competition : When species or individuals “fight” for the same resources. –E.g., Food, shelter…. COMPETITIVE EXCLUSION – Extinction of a species due to direct competition. KEYSTONE PREDATOR/SPECIES - A predator that causes a large increase in diversity of its habitat. The “fight” may be indirect … individuals may never directly contact each other. Two species with similar needs for same limited resources cannot coexist. http://www.butler.edu/herbarium/prairie/prairie42004.jpg Losing a keystone species usually disrupts many ecological relationships.

5. Herbivory : A primary consumer feeds on a producer. A fruit bat eating a papaya http://www.smilinglizard.com/1a291aa0.jpg http://images.inmagine.com/168nwm/creata s/cr15169/cr15169065.jpg A woodchuck eating wild clover

6. Predation : A consumer feeds on another consumer. http://nationalzoo.si.edu/Publications/ZooGoer/2006/3/IMAGES/lion_zebra.jpg A lion eating zebra. An eagle eating halibut. http://www.citypaper.net/blogs/clog/wp- content/uploads/2007/06/close-up-bald-eagle-eating.jpg

7. Symbiosis : A long-term relationship where two species live closely together and at least one benefits directly from the relationship. http://www.floridastateparks.org/maclaygardens/images/wallpaper/1024-PL-MAC-Symbiosis-MarkFerrulo.jpg

8. Mutualism : Both organisms benefit from the relationship. Win-Win situation! http://tumi-educational-resources.org/Educational%20%20Videos.htm

9. Commensalism One organism benefits, the other one is unaffected. Win-Neutral relationship

10. Parasitism One organism benefits, the other one is harmed! Win-Lose relationship Parasites rarely kill their hosts…it would require them to get another one!

11. Ecological Relationships Biological Magnification — Increasing concentration of poisons in organisms in higher trophic levels in a food chain or web.

12. Biological Magnification- accumulation of increasing amounts of toxin within tissues of organisms. Video on Biological Magnification