Interactions in ecosystems

Interactions in Ecosystems 3 main ways organisms interact with each other: 1. Competition 2. Predation 3. Symbiosis

1. Competition interaction between 2 or more organisms competing for the same resource in a given habitat in order to coexist in an area, species need slightly different niches to feed off the same land Competition can occur between the same species eg. bulls compete to determine who will mate with the female

2. Predation Occurs when 1 organism eats another to obtain food Animals use camouflage to avoid predators eg. this toad is hardly distinguishable from its surroundings

Predation monarch butterflies defend by having an awful taste and bright colors species sometimes use mimicry (looking like another organism) to avoid predators and survive eg. Viceroy butterfly looks like a monarch

3. Symbiosis close interaction between 2 different species in which members of 1 species live in, on, or near members of another species eg. the clownfish and the anemone 3 types: A. Mutualism B. Commensalism C. Parasitism

A. Mutualism Mutualism – both species benefit from the partnership eg. the caterpillars have nectar organs which the ants drink from and the acacia tolerates the feeding caterpillars. The ants provide protection for both the plant and the caterpillar

B. Commensalism Commensalism – one species benefits from the relationship and the other lives without any harm or benefit eg. the bird gets food from the cow’s back but the cow is unaffected

C. Parasitism Parasitism – one species benefits at the expense of another (a parasite lives in or on another organism) ex. the tick feeds off the dog’s blood

Homework 1. Classify the following interactions as mutualism, commensalism, or parasitism. A yucca moth caterpillar feeds on the yucca plant and pollinates the yucca plant. Lice feed harmlessly on the feathers of birds. A cowbird removes an egg from a robin’s nest and replaces it with one of its own. An orchid plant grows on the branch of a tree. The tree remains healthy. 2. When similar species live in the same habitat, explain how competition between these species is reduced.  3. When a predator catches its prey, it may appear that the prey species suffers. But there are benefits to this type of interaction for the prey species as well. What are two ways in which the prey species may benefit from the predator hunting them?