Symbiosis is a relationship between different species in which at least one species depends upon the relationship to survive

Symbiotic relationships Symbiosis Mutualism (+ +) Commensalism (+ 0) Antagonism (+ -) Parasitism Predation Competition Amensalism (- 0)

Antagonism - Predation One individual (predator) captures, kills, and consumes another individual (prey) Common Defenses Against Predation Flight Mimicry Camouflage Chemicals/Physical Structures Bright Colors

Herbivore-Plant Interactions An herbivore grazing on a plant is another example of predation. Usually, only part of the prey is eaten by the predator. Photo Credit: Rhett A. Butler @ mongabay.com

Antagonism - Competition Competition in an interaction between two organisms that are using the same resources Competition within the same species= intraspecific Competition between different species= interspecific One organism better uses a resource leaving less for other species

Example: Interspecific Competition Two species of barnacles on rocky coasts often compete for space. The smaller species (Chthamalus) is unable to compete as well as the larger species (Balanus). However, Chthamalus can survive drying better than Balanus, so it can live higher up on the rocks.

Experiment: Interspecific Competition In Scotland, Joseph Connell studied interspecific competition in these two barnacles. In places where both barnacles were present, he removed the Balanus barnacles from the rocks.

Experiment: Interspecific Competition When Balanus barnacles were removed, the Chthamalus barnacles moved down into the vacant area. This showed that Balanus was outcompeting Chthamalus in the lower zone.

Experiment: Interspecific Competition At other sites where both barnacles were present, he removed Chthamalus barnacles from the rocks. The vacant areas remained unoccupied. This showed that Balanus was not able to survive in the upper zone.

Antagonism - Parasitism One individual is harmed and one benefits Parasite feeds on the host No immediate death

Mutualism Both species benefit Pollination

Commensalism One species benefits and the other is not affected Cattle Egrets and Livestock

Ammensalism one species is harmed or inhibited and the other species is unaffected shading out of one plant by a taller and wider one the inhibition of one plant by the secretions of another

Species Interactions Symbiotic Relationship Species 1 Species 2 Mutualism + Benefits Commensalism Neutral Antagonism (Parasitism, competition, predations) - Harmed Ammensalism

http://education. nationalgeographic http://education.nationalgeographic.org/activity/ecological-relationships/ https://www.youtube.com/watch?v=fxrzdhHjf0Q&list=PL0EA301D130F3DB40 Clips 1-3