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Survival Adaptations. Survival Adaptations. Intense selection pressure to find survive predation Leads to co-evolutionary relationships between predator and prey . Interspecific Interactions between Predator and Prey. Co-evolutionary Arms Race. Predator and prey designs are never perfect
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Survival Adaptations • Intense selection pressure to find survive predation • Leads to co-evolutionary relationships between predator and prey
Co-evolutionary Arms Race • Predator and prey designs are never perfect • Costs and benefits are incurred • http://www.youtube.com/watch?v=Xlkj-NoZyn0
Mobbing Behavior • Anti-predator behavior • Individuals work to deter predators by attacking or harassing • Mobbing behaviors include • Pecks, dive bombing, squacking and defecation • http://www.youtube.com/watch?v=6ecEZuIcHxs
Mobbing Behavior Function • Advertise physical health • Distract from offspring • Warn offspring of predator presence • Lure predator away
Meerkat • Grasslands, Scrub, deserts • Cooperative species • Live in social groups • Colonies of up to 30 individuals • Family groups • Use mobbing as an anti-predator response • Deter predators • Gather information to assess risk • Learned behavior • http://www.youtube.com/watch?v=ncoTWKtGNb4
Kangaroo Rats • Nocturnal desert rodents • http://www.youtube.com/watch?v=wkJLHnYy_G0
Black-headed Gull • Nesting colonies • Flat often exposed areas • Predators • Weasels, foxes, coyotes
Killdeer • Shorebird • Ground nester • Feigns injury to distract predators • http://www.youtube.com/watch?v=AaODt7SCsGk&feature=related
Black Bear • Mother bear cares for offspring • Extended parental care • Cubs stay with sow for approximately 17 months • Female travels with cubs as she forages • http://www.youtube.com/watch?v=Bkwy0scRXBU
Cost Benefit Analysis • Adaptive value of behaviors when fitness benefits outweigh and fitness costs • Fitness benefit • Positive effect of a trait in increasing reproductive fitness • Fitness cost • Negative effect of a trait results in a decrease of reproductive fitness
Cost Benefit Analysis • Mobbing a predator can be a risky behavior • Increases exposure to predators • Mobbing behaviors are energetically costly • High caloric activity • Mobbing benefit must outweigh costs • Increase survival • Increase fitness
Causation • Proximate • Physiological foundation • Ex. Presence of Neurotransmitters • Genetic component • Ultimate • Adaptive value to reproductive success • Phylogenetic history (Macroevolution)
Phylogenetic History • Evolution of mobbing behavior in Black-headed gull • If ancestral gull was a ground nester, evolution of mobbing would have been an adaptive behavior • More than 50% of gulls use mobbing behavior, supports hypothesis
Cliff Nesting Gulls • Some species of gulls nest on cliffs • Location protects eggs and young • Fewer predators results in different predation pressure • Mammals unable to scale cliffs, predatory birds unable to maneuver in coastal winds
What Came First Ground Nesting or Cliff Nesting? • Two possible explanations
Occam’s Razor • Aka Principle of Parsimony • Simplest possible explanation involving fewer evolutionary transitions are more probable than than complicated alternatives
Divergent Evolution • Evolution of differences among closely related species that live in different environments, with different selection pressures
Convergent Evolution • Independent evolution of similar characteristics in two or more unrelated species that live in similar environments with similar limiting factors • Mobbing behavior is an example of convergent evolution
California Ground Squirrel • Complex suite of predator-prey interactions • Mobbing • Tail shaking • Antivenom • Risk assessment
Mud- Puddling • Aggregation of insects (mostly butterflies) on wet soil, rocks with specific mineral content, dung or carrion • Behavior to acquire water, salts and amino acids • http://www.youtube.com/watch?v=VdlIjRCc_sM&feature=related
Dilution Effect • Adaptive benefit of gregarious behavior • For any one predator attack, the larger the group of prey animals, the smaller the chance that any particular individual will be the victim
Mixed Flocks • Multiple species will aggregate • Despite increased competition • Dilution effect • Increased vigilance
Synchronous Breeding • Breeding when members of a population tend to breed at the same time • Hatch or metamorphis at the same time • Anti-predator response • Dilution effect
Mayfly Hatch • Synchronous metamorphism • Dilution Effect
Black Fly Hatch • Synchronous breeding • Dilution effect • http://www.youtube.com/watch?v=e0qDq6DqgoA
Organized Defense • Cooperation among individuals to fight off predators • Costs • High concentration of individuals increases intraspecific competition • Benefit • Group attack is a more effective defense against predators
Ants, Bees & Wasps • Cooperation among individuals to defend nest • http://www.youtube.com/watch?v=HL3sHuK3iGE
Sawfly • Feed on noxious food sources • Pine needles, eucalyptus • Segregate noxious compounds in digestive system • Use startle response to deter predators • http://www.youtube.com/watch?v=rmYt3j1Id3Q&feature=related • http://www.youtube.com/watch?v=WgSj9VuDcVU&feature=related
Cryptic Coloration • Anti-predator response that involves camouflage • Defense behavior often associated with solitary individuals • Involves suite of morphological and behavioral characteristics • http://www.youtube.com/watch?v=MK6nlsOZpuU
Cuttlefish & Octopus • High predation pressure • Specialized skin designed for crypsis • Elaborate sensory and nervous systems • http://www.youtube.com/watch?v=2x-8v1mxpR0&feature=related • http://www.youtube.com/watch?v=__XA6B41SQQ&feature=related • http://www.youtube.com/watch?v=7NQUqR_YpsA&feature=related
Edge Detection • Use of disruptive color pattern to conceal appearance by breaking up outline of body
Edge Detection • Use of disruptive structures to conceal appearance by breaking up outline of body
Behavioral Crypsis • Skipper butterfly larva • Conceal their location by living in a rolled up leaf • Anti-predator defense for visual predators • Eject fecal pellets from shelter • Anti-predator defense for odor searching predators
Behavioral Crypsis • Use increase in blood pressure to launch fecal pellet held at anus • Launch up to 40 times their body length at a Speed of 4.2 feet per second • Equiv for 6ft human is 240ft
Warning Coloration • Honest signal warning potential predators against harm to avoid becoming prey
Monarch Butterfly • Larva feeds on plants of milkweed family • Toxin is stored in tissues • Color signals unpalatability
Warning Coloration • Blue Jays will sometimes consume • If survives will avoid in future
Warning Coloration • Warning color may signal other danger
Mimicry • Mimic or copy of another animals survival adaptation • Typically involves color and or behavior
Mimicry • Spicebush caterpillar • Mimic as both larvae & adults • Young larvae small and dark brown • Older larvae green • http://www.youtube.com/watch?v=uQhWDBzlLCM
Self Mimicry • Refers to the form of mimicry when one species is mimicking the body part of another • Increases survival during an attack • Dishonest mimicry
Eye Spots • Allow prey species to startle predator and increase chances of escape • Provide a false target so predator attacks non-vital body part
Batesian Mimicry • Refers to the form of mimicry when two or more species have a similar appearance, but only one of the species has an anti-predator adaptation • Dishonest mimicry
Batesian Mimicry • Honey bee and Bee fly
Batesian Mimicry • Coral snake and Mountain King snake • http://www.youtube.com/watch?v=FvDpbjSRpuc&feature=related