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) 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 Hawkmoth Larva Batesian mimicry: A harmless species mimics a harmful one. Green parrot snake

Fig. 54-5d Cuckoo bee Müllerian mimicry: Two unpalatable species mimic each other. Yellow jacket (d)

Defenses of Prey- Camouflage

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