Review of Ecology

1. Review of Ecology Chap. 2.1 to 2.2

2. Universe Galaxies Biosphere Solar systems Planets Earth Biosphere Ecosystems Ecosystems Communities Populations Realm of ecology Organisms Communities Organ systems Organs Tissues Cells Populations Protoplasm Molecules Atoms Organisms Subatomic Particles

3. Biotic vs. Abiotic Factors:Influences on each other Biotic: Biological influences on organisms Abiotic: Physical, non-living parts of an ecosystem

4. Levels of Organization of the Biosphere • Biosphere: All life on Earth and the parts of Earth that support life • Organized into specific levels

5. Biosphere organization: smallest to largest • Species: Similar organisms that can breed and produce fertile offspring • Population: Group of individuals of the same species that live in the same area http://alumnus.caltech.edu/~kantner/zebras/pictures/zebra_b.jpg http://www.south-africa-tours-and-travel.com/images/mznp-mountain-zebras-vince-o-sullivan-mountainzebranationalpark.jpg

6. Biosphere organization • Community: Different populations that live in the same area • Ecosystem: All of the organisms that live in a place, together with their physical environment http://www.safari-guide.co.uk/images/gallery/zebra_wildebeest.jpg

7. Biosphere organization • Biome: a group of ecosystems that share similar climate and typical organisms • Biosphere: All life on Earth and parts of Earth that support life.

8. How this classroom fits in?

9. Interactions within Communities • Community: group of populations in a given place and time • Populations within a community can interact in manner that is beneficial or harmful http://www.mapecology.altervista.org/index_clip_image005.jpg

10. 6 Possible Interactions

11. Symbiosis: “Living Together” • Close and established interactions among populations living in a community • Include: • Mutualism • Commensalism • Parasitism http://www.scienceclarified.com/photos/symbiosis-real-life-applications-2942.jpg

12. Mutualism (+/+): Both benefit • Both species obtain a benefit from the relationship. • Obligatory: one species is totally dependent on other • Nonobligatory: can survive without relationship http://www.scienceclarified.com/photos/symbiosis-real-life-applications-2942.jpg

13. Commensalism (+/o): One helped; One neutral • Can involve using another for: • transportation (remora eel and shark), • housing (Spanish moss on tree; hermit crab in old shell) • to obtain food (fish and shark) http://www.bayouvermilion.org/pictures/Plants/Spanish%20Moss%20w%20Blue%20Heron%20in%20Tree.jpg http://2.bp.blogspot.com/_XMkx9D8aY_c/TRv0QDzUU-I/AAAAAAAAE3M/7G2MqueHDBo/s1600/104815-shark.jpg

14. Neutralism • Neither affected by other • Does not often occur in reality • Applies when interaction is negligible

15. Amensalism • One species suffers while the other is neutral • Example: plant secretes chemical that inhibits growth around it (allelopathy)

16. Predation/parasitism (+/-):One is helped; one is harmed • Predator = organism that is capturing and eating another • Prey = organism being eaten http://per.ornl.gov/Lindroth1.jpg

17. Predation/parasitism (+/-):Forms of Predation • Carnivory: Animal kills and eats animal • Parasitism: Predator lives within host, weakens it but doesn’t kill it • Parasitoidism: Lays eggs inside host and consume it as larvae grow • Herbivory: Foraging on plants http://www.brotherstree.com/tick-on-skin-744826.jpg

18. Predator-Prey Dynamics • Predators affect the size of prey populations and determine the places that prey can survive and grow. • Amount of prey determine how much predator population can grow. http://braddlibby.files.wordpress.com/2010/08/lions-gazelle-1.jpg?w=425

19. Competition (-/-): Both harmed. • Competition occurs when organisms attempt to use the same limited ecological resource in the same place at the same time • Both end up in a more limited “niche” than may be possible for them without competition. http://myrmecologylab.files.wordpress.com/2010/09/3-lugubris-e-afidi-dettaglio2.jpg

20. Niche: How an organism “makes a living” • Niche: full range of physical and biological conditions in which an organism lives and how it uses those conditions • One’s niche is determined first by tolerances and habitat • Tolerance: ability to survive in range of conditions • Habitat: species tolerance for specific conditions determine the general place where it can live -- its “habitat.”

21. Niches • Physical Aspects: All abiotic factors needed for survival • Temperature, moisture etc. • Biological Aspects: All biotic factors needed for survival • How and when reproduce, food it eats, how it obtains food

22. Niche generalists vs. specialists • Generalists: Broad niches; can live in wide range of environments (cockroaches, mice, humans) • Specialists: Narrow niches; may have difficulties with environmental changes • Q: Which has the advantage in a stable ecosystem?

23. Niches and Competition • Competition can limit the niche that the species can occupy • Species may be able to survive and reproduce under larger range of conditions but is limited by competition http://www.physicalgeography.net/fundamentals/images/niche.gif

24. Competitive Exclusion Principle • No two species can occupy the same niche in the same habitat at exactly the same time • The better competitor excludes the weaker one

25. Dividing Resources • Competition is niche overlap • Each species uses a portion not able to be used by another species. • Competition helps determine species and niches each species occupies.