Everything is connected to everything else Ecology Putting it all together… study of interactions between creatures & their environment, because… Everything is connected to everything else

The Biosphere The portion of Earth that supports living things Composed to two parts Biotic factors The living organisms that inhabit and environment all plants & animals living in an area Abiotic factors the physical parts of an organisms environment soil, rock, temperature, moisture, sunlight

Levels of Biological Organization Population – a group of organisms, all of the same species, which interbreed and living in the same area at the same time Biological community – made up of interacting populations in a certain area at a certain time (example: different types of flowers growing in the same field) Ecosystem – made up of interacting populations in a biological community and the community’s abiotic factors Species  Population  Community  Ecosystem  Biosphere

Creatures living in their environment Populations

Community Ecology Community Ecology study of interactions among all populations in a common environment To answer: In what way do the populations interact?

Niche vs Habitat A habitat where an organism lives its life An organism’s niche is its ecological role High tide Competitive Exclusion If Species 2 is removed, then Species 1 will occupy whole tidal zone. But at lower depths Species 2 out-competes Species 1, excluding it from its potential (fundamental) niche. Species 1 Low tide Chthamalus sp. Species 2 Fundamental niches Realized niches Semibalanus sp.

Symbiotic interactions competition (-/-) compete for limited resource Food, mate, territory predation (+/-) One animal eats another parasitism (+/-) One organisms feeds off of another mutualism (+/+) Both organisms benefit commensalism (+/0) One benefits and the other doesn’t change

Symbiosis- interactions between organisms mutualism +/+ …not very funny for a clown fish commensalism +/0 predation +/- competition -/-