Symbiotic Relationships

What are Symbiotic Relationships??

• Symbiosis is the close relationship between two or more organisms of different species, often but not necessarily benefiting each member.

Ectosymbiosis and Endosymibosis

• Ectosymbiotic- wherein one organism lives on another organism

• Endosymbiotic- wherein one organism lives inside another organism

Obligate and Facultative Symbiosis

• Obligate- the relationship is essential for the life of at least one of the organisms

• Facultative- where the relationship is beneficial to the organisms, but not essential for survival

Mutualism• The two organisms involved in this

relationship both benefit from each other.

What benefits are provided in each

picture?

Examples of Mutualism:

Examples of Mutualism• The Egyptian plover and the crocodile: – The plover eats the decaying meat stuck in the

crocodiles teeth. The bird gets food and the crocodile gets dental care.

• The clown fish and the sea anemone:– The clown fish lives in the sea anemone. The

anemone gets nutrition from the fecal matter of the fish and the fish gets protection from predators.

• The oxpecker and the zebra:– The oxpecker lands on the zebra and eats ticks and

other parasites that live there. The oxpecker gets food and the zebra gets pest control.

Examples of Mutualism• The bee and the flower:

– Bees collect nectar from flowers which they make into food. When they land on the flower they get pollen stuck to their bodies. They spread this pollen to other flowers, pollinating the plants.

• The spider crab and the algae:– The spider crabs live on the shallow ocean floor. The algae lives

on the crabs. The algae helps the crabs blend in and the algae gets a good place to live.

• The bacteria and the human:– Bacteria lives in the intestines of humans. The bacteria helps the

human by digesting food that the human cannot. They get a meal and the human is able to digest the food they eat.

• In this relationship, one organism benefits while the other is unaffected (doesn’t benefit and isn’t harmed)

Commensalism

Commensalism

• What is happening in each relationship?

Examples of Commensalism• The cattle egret and cows:– When cattle graze, they stir up and move many insects

that were nesting in the grass. The egret then feeds upon the insects.

• Sedentary crustaceans/barnacles:– They attach themselves to rocks or whales. When the

whales travel the barnacles get access to nutrient rich waters an sometimes food that is left behind y the whale.

• The desert holly shrub:– Provides shade for growing creosote bushed beneath it.

• The fringe toed lizard:– Will stay in abandoned desert rat holes.

Examples of Commensalism• The caribou and the artic fox:

– The fox follows the caribou while it looks for food. When the caribou digs up the snow to get to the lichen underneath they stir up some of the subnivean mammals. The foxes then hunt these animals.

• Remora sharks and whales:– The Remora sharks have an adhesive disk on their dorsal surface.

They use this to attach to whales and then feed on the remains of the whale’s food.

• Birds and army ants:– The birds follow the ants which stir the flying insects resting on the

ground. He birds then catch and eat the insects.• Monarch and Viceroy butterflies

– The monarch butterfly contains cardiac glycosides which are poisonous to vertebrates. This keeps animals from eating the monarch butterflies. The viceroy butterfly mimics the monarch butterflies patterns and therefore are not eaten.

Parasitism• In this relationship, one organism is harmed

while the other benefits

Parasitism• How do you think each represents parasitism or

how do you think the organism shown is parasitic?

Examples of Parasitism

• Mosquitos: suck the blood of their prey• Oak Treehoppers: suck sugar-rich juices from

the phloem of trees• The squawroot: a flowering plant that gets

energy by tapping into an oak tree’s roots• Sea Lamprey: A sort of temporary parasite. The

lamprey latches onto a fish and holds on with its teeth and rasps away the skin. This leaves an open wound for them to feed off of.

Examples of Parasites

• The horsehair worm: It starts as an egg in a puddle. When the puddle dries out a grasshopper usually comes along and eats it. It then burrows into the insects gut and grows. When it is an adult it produces chemicals that make the insect seek out water and jump into it. The worm will exit the grasshopper and finish out its life in the puddle. The grasshopper may survive the ordeal if it doesn’t drown.

Examples of Parasites

• Cricket: It lives in an ant’s nest and disguises itself with a chemical that makes the ants think it is just another ant. It roams the nest and gets the ants to feed it.

• Leeches: thought of as ectoparasites. They attach to a vertebrate host and take a blood meal before dropping off the host.

• Lice: Parasitize humans. They attach to the hairs of the body or head and then suck blood from the host. It is easy to remove the adults but not the eggs.