The Ecosystem

Ecosystem A community of interdependent organisms and the interactions with the physical environment in which they live. It can also be defined as the abiotic and biotic factors and the interactions between them. The interaction between organisms and the environment is the key!

Differentiate between the following terms: Organism Species Population Community Niche Habitat

In your notebook, draw a picture of a bunch of little organisms Label: The organisms of the same type (Species) Circle: individuals of the same species (Population) Draw interactions between the populations (Community)

A habitat differs from a niche. A habitat is all aspects of the area in which an organism lives. biotic factors abiotic factors An ecological niche includes all of the factors that a species needs to survive, stay healthy, and reproduce. food abiotic conditions behavior

Resource availability gives structure to a community. Species can share habitats and resources. Competition occurs when two species use resources in the same way. Competitive exclusion keeps two species from occupying the same niche.

Competitive exclusion has different outcomes. One species is better suited to the niche and the other will either be pushed out or become extinct. The niche will be divided. The two species will further diverge.

Ecological equivalents are species that occupy similar niches but live in different geographical regions. Madagascar South America

If a group of mantella frogs were transported to the ecosystem of the poison dart frogs, what might happen to the 2 species populations? As ecological equivalents, they share a similar niche. The population better suited to the niche might deprive the other of resources, causing the other to die off. OR One population might respond to limited resources by altering its niche.

This could drive the native species to extinction Considering the competitive exclusion principle, why may it be harmful to transport a species such as a rabbit, to another habitat where it currently does not exist? If a new species is introduced to an area, it may occupy a similar niche as a native species and be better adapted for the niche to have no natural predators. This could drive the native species to extinction

Limiting factors An abiotic factor can limit the population size if there is too much or too little of it. Even if there is the right amount of other factors Examples to consider: Sunlight Precipitation Salinity Nutrients in the soil

Tolerance Range Every population thrives in an optimal range of abiotic factors. Beyond this range, one finds less and less numbers of these organisms.