1. Interactions within Communities SBI4U

2. Ecological Niches Community All populations in a given ecosystem at a specific time Types of niches Ecological niche The role of an organism within the biotic and abiotic factors of the environment Fundamental niche The theoretical role an organism can reach within the environment Realized niche The actual role an organism can achieve due to limiting factors in the environment

3. Types of Interactions Interspecific Competition Interactions between individuals of different species for common resources Intraspecific Competition Interactions between individuals of the same species for common resources

4. Coevolution Process in which one species evolves in response to the evolution of another species. Eg. Hummingbird beaks that have adapted ‘evolved’ over time to have the shape of the plant/flower the pollinate.

5. Types of Interactions Types of interactions Competition Interactions that may be harmful to both species Predation/Herbivory Beneficial to one species, loss of life for the other Symbiosis Parasitism Beneficial to one species, harmful but not lethal for the other Mutualism Beneficial to both species Commensalism Beneficial to one species but does not affect the other

6. Competition Interference competition Different species aggressively fighting over resources Exploitative competition One species out consuming the other for resources Resource partitioning Avoidance of competition by occupying different ecological niches

7. Predation A predator-prey relationship is when one species feeds on another and the relationship can affect the population of both species Some species have developed defense mechanisms Camouflage, chemical defence, behavioural defense, mimicry, spines & armour. E.g. horns, hooks, spines, needles, as well as chemical defences, also hiding and camouflage

8. Symbiosis Mutualism Obligatory mutualism is when both species need each other for survival Commensalism A relationship where one species benefits and the other neither benefits or is harmed Parasitism Microparasites Microscopic parasites (plasmodium) Macroparasites Larger parasites (tapeworm) Endoparasites Parasites that feed inside the body Ectoparasites Parasites that feed outside the body Social parasites Parasites that manipulate other organisms to complete their life cycle (cowbird)

9. How are these species influencing each other?

13. Interspecific Interactions SPECIES ASPECIES B Positive (+)Neutral (0)Negative(-) Positive (+)MUTUALISM -cowbirds + cows Neutral (0)COMMENSALISM -barnacles on whales NEUTRALISM - probably non- existent Negative (-)PREDATION or PARASITISM - only the predator or the parasite benefit AMENSALISM - bread mould produces penicillin that kills bacteria COMPETITION - both species have decreased fitness

14. Disruption of Equilibrium Things tend to stay as they are Natural disasters and the introduction of invading species Purple loosestrife Rabbits in Australia Ecological disturbances that that change the equilibrium

15. Credits http://commons.wikimedia.org/wiki/File:Edge-of-a-wood.JPG http://commons.wikimedia.org/wiki/File:CulexNil.jpg http://commons.wikimedia.org/wiki/File:Water_Buffalo_fight.jpg http://commons.wikimedia.org/wiki/File:Wolves_and_bones.jpg http://commons.wikimedia.org/wiki/File:Common_clownfish_curves_dnsmpl.jpg http://commons.wikimedia.org/wiki/File:Jenga.gif http://commons.wikimedia.org/wiki/File:Homework_-_vector_maths.jpg http://commons.wikimedia.org/wiki/File:Red-billed_oxpeckers.jpg http://commons.wikimedia.org/wiki/File:Hummingbird_Texas.jpg