23 lecture April 17

23 lecture April 17 - Human Ecology The history of human...

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1 1 Human Ecology The history of human populations An ecological puzzle: The recent growth of the human population Testing alternative solutions to the puzzle Exam average = 80 Final exam will incorporate some questions based on exams 1-3 2 Another test of the possible role of predators in controlling herbivores Oak tree, herbivorous caterpillar and predatory blue jay 3 Spray = oak tree leaves sprayed with insecticide. Control = leaves left unsprayed and open to birds and insects. Cage = leaves caged so that birds were excluded but not herbivorous insects. 4 26. The data above support which of the following hypotheses? Oaks are not eaten as much as one would think because … a. Predators remove many herbivores from ecosystems c. Both predator pressure and plant defenses contribute to a reduction in herbivore consumption of oak leaves
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2 5 11.A Darwinian adaptation is an attribute that a. helps individuals survive longer than others with alternative traits d. evolved because of reproductive differences among individuals with hereditarily different traits. 6 Why is it also wrong to say that an adaptation is a trait that helps individuals SURVIVE? Individual gives warning call after seeing coyote 7 Green frogs live 1.5 years on average whereas blue ones live 2.1 years on average. Under what conditions would green individuals replace the blue ones over time? A. No such conditions exist because selection always favors animals able to survive longer. B. Green types would take over if they were stronger and more physically fit than blue frogs. C. Green types would take over if they had more
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This note was uploaded on 09/22/2009 for the course BIO 10067 taught by Professor Plowes during the Spring '09 term at ASU.

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23 lecture April 17 - Human Ecology The history of human...

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