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Parasitoids
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Three general catagories of hunting tactics
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Ambush, stalking, pursuit
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Ambush
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Lie and wait; requires minimal energy; low frequency of success
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Stalking
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Deliberate tracking of prey; quick attack, most time spent encountering prey
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Pursuit
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Minimal search time; pursuit time great
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Predator avoidance; prey strategies
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Variety of defferrent stratigies; suggest predation is a stron selective force;
ex: moth ears have evolbved in responce to bat echolocation
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Aposematic coloration (warning)
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Color pattern advertises distasteful or poisonous nature; black and yellow, brightly colored, orange
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Crypsis
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Camouflage; zebras look like broken grassland, bay pipefish look like eel grass
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Catalepsis
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Frozen posture; movement alerts predator
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Mimicry
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Mimic other undesirable organisms
Mullerian (unpalatable species look alike)
Batesian(palatable species mimics unpalatable species)
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Intimidation
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Startle or scare off predator; toad swallows air to look larger, frilled lizard makes it look bigger, eyespots on moths
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Chemical defense
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Use of chemical irritant
skunks, octopus, bombarder beetle sprays noxious chemicals
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Masting
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Synchronous reproduction; saturate predators
Cicadas (13 or 17 year cycles) white oak trees
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Consumers can limit resource populations
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Sea urchins exert strong control on algae populations... if removed biomass of algae increase and the whole community shifts
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Things that make an effective preditor
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High reproductivity relative to prey, excellent dispersal powers, can switch to alternative food source; keystone predatror
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