ECOLOGICAL RELATIONSHIPS

ECOLOGICAL RELATIONSHIPS

Species – group of similar individuals who can interbreed to produce fertile offspring and further generations may also do so. Population – group of individuals of the same species living in the same area, potentially interacting. Community – group of populations of different species living in the same area, potentially interacting. What are some ecological interactions?

Ecological Relationships No organism is an autonomous entity isolated from its surroundings. An organism's interactions with its environment are fundamental to the survival of that organism and the functioning of the ecosystem as a whole. Ecological relationships can be classified as predation, competition and as symbiosis.

Predation • Predation is when one animal eats another. One species benefits by getting food. The other species is killed.

Competition • Competition is when two organisms are trying to get the same resources: e.g. food, water, sunlight, shelter, mates. Neither species benefits from this relationship, because each organism is taking resources from the other.

Symbiosis • Symbiotic Relationships occur when two organisms live side by side or together. • There are several different kinds of symbiotic relationships: • Parasitism • Neutralism • Commensalism • Mutualism

Mutualism • Mutualism: Both species benefit. The two organisms help each other. An example would be a honey bee and a daisy. The honey bee gets to eat the pollen from the flower. The daisy uses the bee to spread its pollen to other flowers.

Three Kinds of Mutualisms • Energetic & nutritional – transfer of energy/nutrients from one organism to another or to each other • Protective – defense against predators or herbivores • Transport – movement of seeds, pollen, or adult organisms

Energetic Mutualisms Gut symbiont • bacteria in animal guts digest plant materials and produce vitamins/amino acids • benefit to bacteria is a stable environment and a steady food source

Mycorrhizal fungi • fungi that live intermingled with plant roots • fungi uptake nutrients from soil for plants • plants provide carbohydrates to the fungi • mycorrhizal fungi are found in almost every plant • very important where nutrients are limited

Mutualism Lichens are fungi and algae living together. The fungus provides a moist environment for the algae and the algae provides nutrients for the fungus. Birds and mammals eat berries and fruits while the plant benefits by the dispersal of it seeds.

Protective Mutualisms Ants/acacias – • acacias provide food, hollow stems for nesting • ants attack herbivores and kill encroaching plants • wrens nest in the acacias and are protected from predators by the ants (commensalism)

Transport Mutualisms Pollination • flowers trade nectar for pollen transport • can be general or species-specific

Seed dispersal Plants provide nutritious fruit, seeds to encourage dispersal by animals • many seeds require gut passage to germinate • some plants trade-off consumption of some seeds to ensure dispersal

Seed dispersal Why does seed dispersal benefit plants? (why not just drop seeds?) • Avoid pathogens that the parent may harbor • Colonise new habitats where conditions may be better than near the parent • Find locations where germination is more likely (ant nests)

Commensalism • Commensalism: One species benefits. The other species is unaffected. A common example is an animal using a plant for shelter. An American Robin benefits by building its nest in a Red Maple tree. The tree is unaffected.

Commensalism Barnacles get a free ride by attaching themselves to whales. The whale is unaffected. Epiphytes are plants that grow on other plants receiving nutrients from the rain, air and any debris that it catches. It does not affect the plant it is fixed on.

Parasitism • Parasitism: Ones species benefits by living in or on the host, or by stealing nutrients from the host. The other species, the host, is harmed. An example would be a deer tick and a White-tailed Deer. The tick gets food from the deer without killing it. The deer is harmed by losing blood to the tick, and possibly by getting an infected wound.

Parasitism Mistletoe plants tap into the branches of established plants and steal nutrients from the host plant. Some fungi digest moist wood, even on living trees.

Neutralism • Neutralism: Neither species benefits or is harmed. Both organisms are unaffected. An American Goldfinch is a bird that eats mostly seeds. It may share a tree with a Great Crested Flycatcher, which eats mostly insects. Neither affects the other.

Acacia Plant & Ants parasitism The ants lay eggs on acacia tree so they get a nice safe place for their eggs. The acacia covers the infected area with brown flesh (called a gall.) The plant has to use valuable resources to create the gall. What symbiotic relationship is this?

Anemone & Clown Fish This fish lives its entire adult life among the tentacles of a bulb- tentacle sea anemone. Clown fish do not get stung by the anemone as would most other fish so they get protection from predators. The fish often drop food scraps which the anemones can eat. mutualism What symbiotic relationship is this?

Boxer Crab & Anemones This Boxer Crab carries a pair of stinging anemones in its claws or on its shell, which it uses to defend itself from predators. The anemones get to move around which increases their food supply. mutualism What symbiotic relationship is this?

Shark & Remora The remora attaches itself to the shark and saves energy since it doesn’t have to swim, and it gets to snack on the sharks kills. The shark doesn’t get anything. commensalism What symbiotic relationship is this?

Emperor Shrimp & Sea Cucumber This tiny emperor shrimp is riding along on the back of a sea cucumber (a long worm-like starfish relative) while it crawls along a sandy bottom. The shrimp gets to travel around under the protection of its much larger partner, and the sea cucumber doesn't seem to mind. commensalism What symbiotic relationship is this?

Moray Eel & Cleaner Fish This moray eel has a small fish cleaning between its teeth. The eel gets a clean mouth while the cleaner fish gets a nice meal. mutualism What symbiotic relationship is this?

Cattle & Cattle Egrets As these cattle walk around eating grass they stirup lots of insects. The egrets hang around and get a yummy meal of insects. What symbiotic relationship is this? commensalism

Antelope & Ox Bird This ox bird hangs out on the antelope and gets a delicious meal of bugs living on the antelope. The antelope gets rid of parasites. What symbiotic relationship is this? mutualism

Loa Loa Worm & Human This worm infects humans via the blood stream and gets a nice warm safe home there. The human may go blind or have other complications as a result. What symbiotic relationship is this? parasitism

Goby and Alpheid Shrimp This alpheid shrimp (on the right) uses its strong claws like a bulldozer to create a burrow in the sand. The shrimp is nearly blind. It relies upon its partner, the sharp-eyed goby, to warn of danger. When a potential predator approaches, both animals disappear quickly into the burrow mutualism What symbiotic relationship is this?

Wrasse & Batfish Can you see the two cleaner wrasses are removing parasites from a batfish? One of the wrasses has entered the gill slit of the batfish, and may even enter its mouth in search of food. The batfish gets a bath and the wrasse gets a meal. What symbiotic relationship is this? mutualism

Hummingbird Moth & Flower mutualism This hummingbird moth is drinking the nectar of a flower. The flower gets pollinated (the moth brings pollen from other flowers) and the moth gets a tasty meal. What symbiotic relationship is this?

predation parasitism commensalism commensalism predation parasitism Organising ecological interactions effect on species 1 + 0 - + 0 - mutualism effect on species 2 neutralism competition

ECOLOGICAL RELATIONSHIPS