Succession Is a Series of Predictable Changes That Builds Or Rebuilds and Ecosystem

Ecosystems Test Review

 Succession is a series of predictable changes that builds or rebuilds and ecosystem

 Primary Succession

o Are changes that occur where no ecosystem existed before (brand new)

o There is no soil or plants

o Mosses and lichens are the pioneer species

o Steps:

(1) bare rock

(2) mosses and lichens appear, rock is broken down into soil

(3) small plants such as grasses and weeds take root

(4) As soil becomes more fertile, large plants like shrubs and trees grow

 Secondary Succession

o Are changes that occur after a disturbance (disaster) in an existing ecosystem

o Does not take as long as primary succession

o Soil is present

o Grasses, weeds and small ferns are the pioneer species

o A Climax Community occurs when an ecosystem cannot support any new types of organisms

o Steps:

(1) Natural disaster wipes out the ecosystem

(2) Grasses, weeds and small ferns grow

(3) After the soil becomes more fertile, large plants like shrubs and trees grow

(4) A climax community like a forest develops  Ecosystem: all the living and non-living things that interact in an area

 Adaptations allow an organism to survive

 A niche is an organisms role in the environment; where it fits in

 Interactions in Ecosystems:

o Competition: struggle for resources

o Predation: one organism hunts and kills another

. Predator: does the hunting

. Prey: is the hunted

o Symbiosis: a close relationship between 2 species

. Mutualism: both organisms benefit  

. Commensalism: One organisms benefits; the other is not helped or harmed  

. Parasitism: One organism benefits (parasite); the other is harmed (host)   Producers = Plants Herbivores = rabbits, Prey = all herbivores plus squirrels, mice, seed-eating predaceous (predator) Consumers = rabbits, birds, herbivorous insects insects, Spiders, squirrels, mice, seed-eating insectivorous (insect eating) birds, herbivorous insects, Carnivores = predaceous birds, toads, predaceous (predator) (predator) insects, Spiders, insects, Spiders, insectivorous (insect eating) Predators = predaceous insectivorous (insect eating) birds, toads, snakes, hawks (predator) insects, Spiders, birds, toads, snakes, hawks and owls, foxes insectivorous (insect eating) and owls, foxes birds, toads, snakes, hawks and owls, foxes

Competitors = foxes, hawks and owls, snakes / insectivorous (insect eating) birds, toads / predaceous (predator) insects, Spiders