NICHE AND COMPETITION

NICHE Range of physical and biological conditions in which a species lives and the way the species obtains what it needs to survive and reproduce * The role or function of an organism in its ecosystem

Example of Niche A jaguar’s niche Native: South America Diet: mice, frogs, fish, turtles, deer Reproduction: year round mating, multiple cubs stay with mom for up to 2 years Time of activity:diurnal * All of the variables that contribute to how an organism affects its ecosystem makes up its niche.

Resources in a niche Resources for which species may compete: Food Water Shelter Mates Nesting sites Sunlight soil

Tolerance Ability to survive and reproduce under a range of environmental circumstances. * The organism must expend more energy to maintain homeostasis, and so has less energy left for growth and reproduction.

Physical and Biological Aspects of a niche Physical - Abiotic Ex: Most amphibians lose/absorb water through their skin, so they must live in moist places. Biological – biotic Ex: Birds on Christmas Island in the Indian Ocean, all live in the same habitat but they prey on fish of different sizes and feed in different places.

Competition Occurs when organisms attempt to use the same limited ecological resource in the same place at the same time. * Because communities live in the same area, they need to compete.

Competition Examples: In a forest, for example, plant roots compete for resources such as water and nutrients in the soil. Animals compete for resources such as food, mates, and places to live and raise their young. Competition can occur both between members of the same species (known as intraspecific competition) and between members of different species (known as interspecific competition).

The competitive exclusion principle

No two species can occupy exactly the same niche in exactly the same habitat at exactly the same time. * If two species attempt to occupy the same niche, one species will be better at competing for limited resources and will eventually exclude the other species.