Bellringer “As more individuals are produced that can possibly survive, there must…be a struggle for existence, either one individual with another of the same species, or with the individuals of distinct species, or with the physical conditions of life.” - Charles Darwin How does this quote relate to niches and competition?

Section 2 How Species Interact with Each Other

I. An Organism’s Niche A._____ the unique role of a species within an ecosystem niche 1.A niche includes an organisms: a.physical home b.environmental factors c.species interactions

3.Think of a niche as the organism’s job or function 2.Habitat is different from niche a.Habitat is location B.Niche example, Fruit Bat: 1.Lives in trees and caves 2.Pollinates flowers 3.Spreads seeds 4.Interacts with hawks and owls

II. Ways In Which Species Interact A.___________ relationship in which different individuals or populations attempt to use the same limited resource Competition 1.Can occur: a.Between species b.Within species c.Indirectly

B.Between species: 1.Lions, Hyenas, and Cheetahs all compete for the same food on the African savannah’s C.Within species: 1.Two different loblolly pines growing close to each other a.Think of this as more of a resource limitation

III.Indirect Competition: 1.Both mice and man will consume crops such as corn, however in this relationship these organisms will rarely interact A.Two closely relates species sharing a habitat resulting in Niche restriction or Niche differentiation: Examples…

3.Two species of mice, one nocturnal and one diurnal, both feed on insects. They feed at different times 2.Two monkey species feed at different heights within a tree

IV.Predation, Parasitism, Mutualism, and Commensalism A.Predator/Prey – One organism eating another Example: snake (predator) eating a mouse (prey)

B.Parasitism – An organism that takes nourishment from an organism 1.Two parts: a.Parasite – organism that feeds on another organism b.Host - organism that is providing nourishment to the parasite

2.Different from a predator b/c the parasite spends all or most of its life in or on the host

C.Mutualism – Two organisms living in harmony helping each other out 1.A butterfly and a flower. How do they help each other?

D.Commensalism – One species benefits, the other is not harmed but doesn’t benefit Describe the relationship between the following organisms. How are each an example of commensalism?