Energy Flow and Relationships in an Ecosystem: How do we live together?

Reminder… food chains ALWAYS begin with producers food chain - a diagram that shows how energy flows from one organism to another food chains ALWAYS begin with producers

Food Web [ALL food chains together] a diagram that shows ALL the feeding relationships in an ecosystem most consumers EAT a variety of foods and can be EATEN BY a variety of other consumers [ALL food chains together]

Food Web

Interactions in an Ecosystem Organisms in an ecosystem interact in many ways

Interaction between Organisms competition - when organisms try to use the same resources (such as food) occurs within a population AND between populations

Competition hyenas and lions compete for the meat of the dead buffalo

Interaction between Organisms predation – when an organism kills and eats another organism (prey) X X

Predation the lion is the predator and the zebra is the prey

Interaction between Organisms: Symbiotic Relationships Symbiosis: Any close relationship between species: can be positive or negative Mutualism: both species benefit (+, +) Commensalism: one species benefits, the other is not affected (+, 0) Parasitism: one organism benefits, but the other is harmed (+, -)

Symbiosis = Close Interaction between Organisms mutualism - relationship between two species in which both species benefit

Mutualism The oxpecker bird eats ticks off the impala. The impala gets rid of parasites. (+,+)

Mutualism: The lichen is an algae or cyanobacteria living with a fungus

Lichen Structure Fungus: Provides protection and water storage (hyphae hold a lot of water) for the algae Algae: Provides food through photosynthesis for the fungus

Mutualism (+, +) The cleaner wrass gets food; the moray eel gets rid of mouth parasites. The clown fish gets protection; the sea anemone gets scraps of food from the clownfish The bee gets nectar; the flower gets pollen moved to the next flower.

Symbiosis = Close Interaction between Organisms commensalism - a relationship in which one organism benefits and the other is unaffected

Commensalism The remora eats food scraps that the shark would not eat; the shark is not affected in any way.

Commensalism The rhino + the egret: as the rhino walks, insects in the grass are disturbed. The egret swoops down and eats. The rhino is not affected in any way. The tree + the epiphyte: The epiphyte grows on a branch on a tree. The epiphyte gets more sunlight. The tree in not affected in any way.

Symbiosis = Close Interaction between Organisms parasitism - one species, the parasite, lives in/on and benefits from the host species. The host is harmed.

Parasitism The wasp larvae live on and feed off the caterpillar. The caterpillar loses nutrients.

Parasitism A tick sucks the blood from a dog or other animal. The tick gets food. The dog or other animal is harmed. A tapeworm lives in the intestine of another animal. The tapeworm gets food. The other animal loses nutrients. Trypanosomiasis (African Sleeping Sickness): This disease is caused by a protist that lives in the brain. The protist gets food. The infected person gets sick.

Summary: Types of Interactions Competition .......... Predation………….. Symbiotic Relationships...... 1) Mutualism ......... 2) Commensalism… 3) Parasitism……….