How do organisms in a community interact?

1. How do organisms in a community interact?

2. Symbiosis “living together” Close and permanent relationship between organisms of different species.

3. There are 3 types of symbiosis • Mutualism: both species involved benefit from the relationship • Commensalism : one species benefits and the other is neither helped nor harmed • Parasitism: one species benefits and the other is harmed

4. Determine which type of symbiotic relationship each example is describing… • Barnacles create home sites by attaching themselves to whales. This neither harms nor benefits the whales. • Yucca flowers are pollinated by yucca moths. The moths lay their eggs in the flowers where the larvae hatch and eat some of the developing seeds. • Mistletoe extracts water and nutrients from the spruce tree to the tree’s detriment. • Ostriches and gazelles feed next to each other. They both watch for predators and alert each other to danger. Since the visual abilities of the 2 species are different, they each can identify threats the other animal would not as readily see. • As buffalos walk through grass, insects become active and are seen and eaten by cowbirds. • Ticks feed on deer blood. • A cuckoo bird may lay its eggs in a warbler’s nest. The cuckoo’s young will displace the warbler’s young and will be raised by the warbler.

5. Predation When one organism hunts and eats another organism Predator = the organism that does the hunting and the eating Prey = the organism that is hunted and eaten

6. Competition When two or more organisms attempt to use a resource at the same time in the same place Usually these organisms occupy very similar or overlapping niches!

7. How is competition reduced? Cape May Warbler Feeds at the tips of branches near the top of the tree Bay-Breasted Warbler Feeds in the middle part of the tree Yellow-Rumped Warbler Feeds in the lower part of the tree and at the bases of the middle branches By having no 2 organisms occupy the exact same niche!!!