Ecology Observing nature

Ecology  The scientific study of interactions among organisms and their environments  Includes descriptive and quantitative data to learn about relationships

Ecology  Biosphere – portion of Earth that supports life  From high in atmosphere to bottom of oceans

Ecology  Ecology includes non-living parts of environment = abiotic factors  Temperature, moisture, air currents, light, soil

Ecology  Living organisms in an environment are the biotic factors  Living things affect others

Ecology  Levels of organization  To understand relationships you have to look at more than one individual  Population  Community  Ecosystem

Levels of Organization  Population is a group of organisms of one species that interbreed and live in the same place at the same time Individual frogs might compete for the same food source

Levels of Organization  Community is a collection of interacting populations  A change in one population may cause change in another population more frogs = fewer flies

Levels of Organization  While population and communities interact, they both interact with their environment  An ecosystem is made up of interactions among the populations in a community and the physical surroundings, or abiotic factors

Levels of Organization  Ecosystems  Terrestrial = on land, forest, meadow, desert  Aquatic = in water, 75% of Earth  Freshwater = pond, lake, stream  Saltwater = ocean

Ecology Organisms in Ecosystems

 Habitat is the place where an organism lives out its life.  Prairie dog burrows in a grassland  Birds in trees of a beech-maple forest

Organisms in Ecosystems  Niche is the role a species has in its environment  Several species may live in the same place, but use different resources = their specialized niche

Organisms in Ecosystems  Some species improve changes of survival by forming relationships with other species  Some relationships benefit one, harm other, like predator/prey relationship  Symbiosis = living together, close relationship between species

Organisms in Ecosystems  There are several kinds of symbiosis  Commensalism  Mutualism  Parasitism

Organisms in Ecosystems  Commensalism = a symbiotic relationship in which one species benefits and the other is neither harmed not benefited  Clownfish lives amongst stinging anemone for protection

Organisms in Ecosystems  Mutualism = a symbiotic relationship in which both species benefit  Ants get nectar from acacia trees and attack any animal that tries to eat from tree. This protection allows trees to live longer.

Organisms in Ecosystems  Parasitism = a symbiotic relationship in which one organism benefits at expense of other organism.  Tick, flea, mosquito