principles predators parasitoids defensesentnemdept.ufl.edu/miller/eny3005/secure/11_lecture.pdf ·...
TRANSCRIPT
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~ 25% of insects are predatory at some life stage…
…and many insects are parasitoids or parasites.
Predator:
Definitions: Ecology – Begon, Harper, Townsend USE THESE DEFINITIONS
Parasitoid:
Parasite:
Definitions: Ecology – Begon, Harper, Townsend USE THESE DEFINITIONS
How do predators find prey?
Foraging strategies: sit and wait
• Conserves energy• Cryptic behavior: defense and offense
Foraging strategies: sit and wait
Aggressive foraging mimicry
Carnivorous fireflies use bioluminescent lures to attract their meals.
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• Photuris firefly female eats males of other firefly species• Females can mimic female flash patterns of five other firefly species
• They use light to find and lure prey
Research by Dr. Jim Lloyd!Foraging strategies: sit and wait
Foraging strategies: sit and wait Foraging strategies: sit and wait
Foraging strategies: active foragingSemi‐random searching
• Patrol microhabitat: time allocated to a patch dictated by prey capture rate
• Eat what they touch
Foraging strategies: active foragingSemi‐random searching Directional searching
• Patrol microhabitat: time allocated to a patch dictated by prey capture rate
• Eat what they touch
• Find prey at a distance• Use chemicals, sound and light• Sharply toothed mandibles,
legs for seizing prey• Often flying predators
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How do actively‐foraging predators find their hosts?
Chemical cues:1. Kairomones2. Synomones3. CO2 – usually by blood‐feeding insects
How do actively‐foraging predators find their hosts?
Chemical cues:1. Kairomones2. Synomones3. CO2 – usually by blood‐feeding insects
Sound / Vibration: e.g., wing beat frequency, cricket songs detected by parasitoids.
Phoresy
The phenomenon of one individual being carried on the body of a larger individual of another species
Another example: botfly eggs
Individual is transported (hitchhikes) ride to prey source.e.g. human botfly captures a blood sucking dipteran (mosquitoes) and attaches a cluster of eggs to phoreticintermediate. When the dipteran takes a blood meal, the rise in temperature induces eggs to hatch.
Phoresy
Phoresy
http://www.cals.ncsu.edu/course/ent591k/torsalo.html
Ectoparasitoids:Parasitoids that live on the outside of their hosts
Endoparasitoids:Parasitoids that live on the inside of their hosts
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How do endoparasitoids cope with the immune responses of the host?
• Incompatible host‐parasitoid interaction results in encapsulation.
A female of the parasitoid wasp Lysiphlebustestaceipes is ready to attack nymphs of its host
How do endoparasitoids cope with the immune responses of the host?
• Incompatible host‐parasitoid interaction results in encapsulation.
• Parasitoids overcome the host immune system in various ways• Avoidance• Evasion• Destruction• Suppression• Subversion A female of the parasitoid wasp Lysiphlebus
testaceipes is ready to attack nymphs of its host
What’s happening here?
Insects use structural, chemical, and behavioral defenses to avoid
each stage of a predator encounter:
Detection Attack Capture Consumption / Parasitism
by predators and parasitoids
Insects use structural, chemical, and behavioral defenses to avoid
each stage of a predator encounter:
Detection Attack Capture Consumption / Parasitism
by predators and parasitoids
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Crypsis: HidingCan incorporate color, texture, pattern, and behavior
http://www.youtube.com/watch?feature=player_detailpage&v=j1xosKrZtDQ#t=21s
Masquerade: Look like something else
Detection Attack Capture Consumption / Parasitism
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Detection Attack Capture Consumption / Parasitism
Startle displays
Detection Attack Capture Consumption / Parasitism
Detection Attack Capture Consumption / Parasitism Detection Attack Capture Consumption / Parasitism
Whistling caterpillars:
acoustic startle displays
Detection Attack Capture Consumption / Parasitism Detection Attack Capture Consumption / Parasitism
Aposematism:advertising
unpalatability
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Detection Attack Capture Consumption / Parasitism
Aposematism:advertising
unpalatability
Aposematism can be acoustic, too.
All of these moths produce aposematic clicks
unpalatable
All of these moths produce aposematic clicks
unpalatable palatable
What is this?Batesian mimicry(ant = model, treehopper = mimic)
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Batesian mimicry(ant = model, treehopper = mimic)
unpalatable models and palatable mimics
unpalatablemodels
mimics
unpalatablemodels
mimics
Batesian mimicry
All unpalatable!
How can this evolve?
Müllerian mimicry
Unpalatable model
All of these moths produce aposematic clicks
Unpalatable mimic Palatable mimicMüllerian mimic Batesian mimic
Detection Attack Capture Consumption / Parasitism
Aposematism often relies on predator learning. After a predator consumes an unpalatable insect,it will avoid attacking similar insects in the future.
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Detection Attack Capture Consumption / Parasitism Detection Attack Capture Consumption / Parasitism
Eisner T , Aneshansley D J PNAS 1999;96:9705-9709
Chemical defenses:spraying
Detection Attack Capture Consumption / Parasitism Detection Attack Capture Consumption / Parasitism
Chemical defenses: Reflex bleeding (autohemorrhaging)
Chemical defenses: Enteric discharge
Detection Attack Capture Consumption / Parasitism
Chemical and structural defenses: urticating hairs
Detection Attack Capture Consumption / Parasitism
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Structural defenses:spines and cuticle
Detection Attack Capture Consumption / Parasitism
Structural defenses: autotomyDetection Attack Capture Consumption / Parasitism
Structural defenses:coatings and constructions
Detection Attack Capture Consumption / Parasitism
Structural defenses:
constructions
Detection Attack Capture Consumption / Parasitism
(Hartbauer 2010)(Kastberger et al. 2008)
Collective defense