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

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