BIOL 1001 Lecture Notes - Lecture 52: Biomagnification, Keystone Species, Trophic Cascade
4 Apr 2017
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Document Summary
Life history-> put energy into constitutive defenses (maintenance), this energy can be used for reproduction & growth instead. Inducible defenses allow for the adjustment of energy allocated for reproduction. No perfect defense mechanisms due to coevolutionary arm race. Prey adapts, so predator adapts and so on. Ex: when the headstand beetle senses a predator, it releases a toxic chemical. There are some animals who got around this. Plants have poor nutrition that prevents herbivores from eating them which reduces herbivore. Bottom-up control in ecosystem refers to which nutrient supply & productivity & type of primary producers control ecosystem structure. Effects that are felt throughout the food web. Keystone species impact on diversity is strong- helps preserve diversity due to being a predator. They limit the population to limit competition & prevent the extinction of some organisms which allows species diversity to go up.
