Relationships in Nature Predation Competition Symbiotic Predation - - PowerPoint PPT Presentation

Relationships in Nature

Predation Competition Symbiotic

Predation

• An interaction in

which one

• rganism kills

another for food

• Ex: green tree

python eats a mouse

C

• mpetition
• The struggle

between organisms to survive as they attempt to use the same limited resources

• Some species will

adapt so that they may coexist

Why can’t two species occupy the same niche? (Think back to 7th grade- C arrying C apacity & Limiting Factors)

S ymbiotic Relationships

• Any two different species of organisms that

live together in a close relationship

• A permanent association
• One member of the relationship always

benefits… the other may also benefit, or it maybe be harmed or unaffected

• There are three forms of symbiotic

relationships: – mutualism – commensalism – parasitism

Mutualism

• A relationship in which both species

benefit

• Examples:

– Bee & Flower – Zebra & Oxpecker – Lichen & Algae

Lichen & Algae

• The lichen furnishes the

algae with water, prevents

• verexposure to sunlight,

and provides nutrients. In return, the algae provides food to the lichen, especially in harsh conditions such as: desert, tundra, high mountains, etc.

• Lichen: stringy stuff
• Algae: (not seen)- cellular level

Zebra & Oxpecker

• The zebra benefits by

having the oxpecker eat the ticks & parasites off the

• zebra. The oxpecker

benefits by receiving nutrition from the ticks & parasites (and the oxpecker does not waste energy searching for food)

Bee & Flower

• The bee benefits

by feeding off the nectar in the

• flower. The

flower benefits by being pollinated by the bee.

• (When the bee

visits one flower, pollen is deposited on it’s body, then the pollen is transferred to another flower by the bee)

C

• mmensalism
• A relationship in which one species
• benefits. The other species does not

benefit nor is it harmed.

• Examples:

– Whale & Barnacles – Cattle Egret & Livestock – Clown Fish & Sea Anemone

Whale & Barnacles

• Barnacles attach themselves to the skin of
• whales. The barnacles “hitch a ride” on the
• whale. The whale is not harmed, nor does it

benefit from this relationship.

C lown Fish & S ea Anemone

• A sea anemone has a

poison on it’s tentacles that are harmful to most fish. The clown fish has developed an immunity to the poison and can use the anemone as

• protection. The sea

anemone does not benefit, nor is it harmed from this relationship.

C attle Egret & Livestock

• Cattle Egrets live in

many pastures

• ccupied by
• livestock. When the

livestock move about the pasture, they kick up bugs and insects. The cattle egrets feed on these bugs. The livestock does not necessarily benefit from this relationship, nor are they harmed.

Video Link

Parasitism

• A relationship in which one species

benefits and the other is harmed, but usually NOT killed.

• Examples:

– Ticks & Dog (or cat, monkey, rabbit, guinea pig, etc) – Mistletoe & Tree – Hookworm & Human Intestine

Tick & Dog (or other mammals)

• The tick takes blood from it’s host (the

mammal). The dog (or mammal) can contract diseases from the tick and can be deprived of a normal blood supply.

Mistletoe & Tree

• Mistletoe is a plant that grows
• n other plants/ trees. The

mistletoe takes water and nutrients from the host tree sap for growth and

• development. The host tree is

not immediately killed, but can be weakened and will become susceptive to breakage, rotting, and fungi

Hookworm & Human Intestine

• The hookworm feeds on the nutrients in

the intestines. The human is harmed because the hookworm takes away important nutrients.

How are predation and parasitic relationships different?