14.2 Community Interactions Warm-Up 14.2 • List 3 open ended questions and 2 close ended questions • Put an asterisk by the most important question
14.2 Community Interactions KEY CONCEPT Organisms interact as individuals and as populations.
14.2 Community Interactions Competition and predation are two important ways in which organisms interact. • Competition occurs when two organisms fight for the same limited resource. – Intraspecific competition – Interspecific competition
14.2 Community Interactions • Predation occurs when one organism captures and eats another.
14.2 Community Interactions • There are three major types of symbiotic relationships. Symbiotic Relationships
14.2 Community Interactions 1. Mutualism: both organisms benefit Honey Love Ants farming aphids Giraffes Oxpecker
14.2 Community Interactions 2. Commensalism: one organism benefits, the other is unharmed Micro World Dust Mites Human Our eyelashes Commensalism Ø are home to tiny mites that feast on oil secretions and dead skin. Without harming Demodicids Eyelash mites us, up to 20 mites may + find all they need to survive be living in one eyelash in the tiny follicles follicle. of eyelashes. Magnified here 225 times, these creatures measure 0.4 mm in length and can be seen only with a microscope. Ø Organism is not affected + Organism benefits
14.2 Community Interactions 3. Parasitism: one organism benefits, the other is harmed. Host: the organism being hurt. Parasitic Wasps & Aphids Leeches 0 Braconid wasp Parasitism Braconid larvae feed on their _ + host and release Hornworm themselves caterpillar shortly before The host hornworm reaching will eventually die as the pupae stage its organs are of development. consumed by wasp larvae. _ 0 Organism benefits
14.2 Community Interactions – Parasitism meet their needs as ectoparasites live outside the body of the host, (such as leeches) and endoparasites live inside the host, (such as hookworms) Leech Hookworm
14.2 Community Interactions Predation vs. mutualism Lady Bird Eats an Aphid Stages of a Ladybugs Life
14.2 Community Interactions 5 Facts/Page HW: 14.3 Pgs. 436-439 Study Guide 14.2 1. Next to each sentence write either intraspecific or interspecific. Which do you think it is? A. Two squirrels race up a tree to reach a hidden pile of food. B. A hyena chases off a vulture to eat. C. Shrubs and grasses compete for sunlight D. Bears hunting for fish fight for space with each other. E. Male sheep butt heads violently for the females. 2. Mutualism 3. Commensalism 4. Parasitism 5. How is parasitism similar to and different from predation? 6. What is the difference between endoparasites and
14.2 Community Interactions In other news… the quiz really is next!