Community Ecology
Definitions to Know
• Population –
• Community -
Community Interaction
• Predator/Prey (+/-)
* Includes herbivores/plants
Predator/prey!
Community Interaction
• Predator/Prey (+/-)
* Includes herbivores/plants
* Co-evolution:
Organisms exert selection pressure on each other
* Advantages of predation????
* “Little Tree”  benefits to population
* Keystone predator  benefits to community
Community Interaction
• Predator/Prey (+/-)
* Includes herbivores/plants
* Co-evolution: Organisms exert selection
pressure on each other
* Adaptations of predators?
* Defenses of prey?
* Plants
* Animals
Adaptations of Predators
Adaptations of Raptors
(birds of prey)
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•
•
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Talons
Beaks
Speed
Keen eyesight
• Good night vision (owls)
• “3D” hearing
• Soundless flight
Defenses of Prey
* Plants
* thorns, chemical
Defenses of Prey
(Animals)
*Warning coloration
* Mimicry
* Camouflage
* mechanical: quills, thorns
Defenses of Prey- Warning Coloration
Defenses of Prey-Mimicry
Fig. 54-5c
Batesian mimicry: A harmless species mimics a harmful one.
Hawkmoth
Larva
Green parrot snake
Fig. 54-5d
(d) Müllerian mimicry: Two unpalatable species
mimic each other.
Cuckoo bee
Yellow jacket
Defenses of Prey- Camouflage
Defenses of Prey- Camouflage
Defenses of Prey- Camouflage
Defenses of Prey- Camouflage
Camouflage: Also adaptation of predator
Camouflage: Also adaptation of predator
Symbiosis
(Two species living in close proximity)
• Parasitism (+/-)
* How different from predator/prey?
* Examples:
• Comensalism (+/0)
* Rare in nature
* Example: Robin and Maple tree
• Mutualism (+/+)
* Examples:
*
Final thought on community….
• Is our view too simplistic?
Fig. 54-1