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Habitat and niche. Mr. Chapman Biology 20. Habitat. A habitat can be described as all of the biotic and abiotic factors in the area where an organism lives.
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Habitat and niche Mr. Chapman Biology 20
Habitat • A habitat can be described as all of the biotic and abiotic factors in the area where an organism lives. • These factors can include all aspects of the environment, including things like trees, other organisms, grass, buildings, watering holes, or pretty much anything you can think of.
Niche • Each species interacts with its environment in a different way. Within an ecosystem, each species has an ecological niche. • An ecological niche is composed of all of the physical, chemical, and biological factors that a species needs to survive, stay healthy, and reproduce.
Habitat & Niche You can think of habitat as the organism’s address. You can think of niche as the organism’s job within that address.
A niche includes several things... • Food – the type of food a species eats, how a species competes with others for food, and where it fits in the food web are all part of its niche. • Abiotic conditions – includes the range of conditions, such as air temperature and amount of water that a species can tolerate. • Behavior – the time of day a species is active as well as where and when it reproduces are factors in the niche of a species.
Something to Think About... • What are the biotic and abiotic factors of your habitat? • What would you say the ecological niche of human beings is?
Competitive Exclusion • Two species that exist in the same habitat may use the same resources in different ways. In other words, they may use them in different contexts of each other’s niches (or for different purposes). • However, when two species want to use the same resource for the same reason, one will ALWAYS be better – or more adapted for the situation.
Competitive Exclusion • Because of this, the other species will be pushed into another niche or else become extinct. • This is known as COMPETITIVE EXCLUSION, and it has a pretty self-explanatory name. • Competitive exclusion can also result in other outcomes...
Alternative Outcomes • Niche partitioning – if two species can naturally divide the resources of the niche to suit each best, they can both continue to survive. • Evolutionary response – the two species could experience what is known as divergent evolution. Larger teeth or some other characteristic may be selected by the environment, allowing each to handle the niche in a different way.