2. Living Relationships
Mutualism
Commensalism
Parasitism + -

3. Ants protecting the acacia from hungry herbivores and pruning away competing plants. The ants live inside inflated thorns at the base of leaves.

4. A lichen growing on the trunk of a mangrove tree
A lichen growing on the trunk of a mangrove tree. The lichen consists of a fungus and an algae growing together. The fungus gets food from the photosynthesising algae and the algae gets a place to live.  

5. In this example an oyster has attached itself to a mangrove pnematophore. The oyster has a solid base to live and the mangrove is not disadvantaged.

6. The Mistletoe penetrates the bark of the mangrove and then takes some of its food from the mangrove. The mangrove is disadvantaged by this.

7. This species (black fish) has only been recorded from the Ryukyu Archipelago. It has a remarkable association with a number of species of gobies, apparently living permanently on their fins, and feeding on the skin between the fin rays.

8. Leafcutter ants carry leaf fragments to their underground nest during a downpour in the lowland rain forest of La Selva Biological Station, Costa Rica. The leaves will become food for the symbiotic fungi cultivated by the ants, which in turn provide food for the ants in the form of filaments swollen with nutrients.

9. Bromeliads in bloom, on a sunlight drenched treelimb in the canopy
Bromeliads in bloom, on a sunlight drenched treelimb in the canopy. (Much like Kudzu in Georgia)

10. The Patella gets it food from the plant, the Euklonia, which is not harmed or damaged in the process.

11. The Egret eats insects off the rhino’s back

12. Butterflies pollinate flowers; receive nectar

13. The protozoa  trichonympha lives in each termite's gut and breaks down cellulose so that the termite can obtain nutrition from its food.

14. Legumes and soil bacteria
Fixed nitrogen is obtained by the legume and the Rhizobium gets a nice place to live with all of the amenities!.

15. A remarkable 3-way relationship appears to have evolved between an ant, a butterfly caterpillar, and an acacia in the American southwest. The caterpillars have nectar organs which the ants drink from, and the acacia tolerates the feeding caterpillars. The ants appear to provide some protection for both plant and caterpillar. Research of Diane Wagner, American Museum of Natural History Southwestern Research Station

16. Sterechinus neumayeri urchins attach algae to themselves as a detachable shield to shed when a potential predator (including anemones, seastars) grabs onto the attached algae. The algae manufactures unpalatable defensive chemicals to avoid getting eaten by the urchin. The urchins pick up loose algae drifting on the seafloor and move fertile drift algae throughout sunlit waters, thereby keeping the fertile algae in the reproductive area with other attached and drift algae.

17. The crinoid Promachocrinus kerguelensis can be seen perched on large volcano sponges Anoxycalyx (Scolymastra) joubini, using the sponge for support to feed higher up in the water column, where they feed off particles and organisms drifting in the current.

18. The senita moth, less than 1/2 inch long, is an obligate partner in a newly discovered mutualism with the senita cactus, whose flowers bloom only after dark and are pollinated almost exclusively by this moth. The moth lays its eggs (top right) in flowers. Larvae (moth caterpillars) which hatch from these eggs later consume some of the fruits. J. Nathaniel Holland of Rice University has studied this mutualism in Mexico and at Organ Pipe Cactus National Monument. His research assistant (right) checks fruits for larvae.

19. A mosquito takes blood from a human- possibly causing disease.

20. The clown fish takes refuge in a sea anenome.

21. Parasitic Aphid Wasp, Lysiphlebus (=Aphidius) testaceipes, depositing egg in aphid

22. Carcasses of aphids after parasitism by Parasitic Aphid Wasp, Lysiphlebus (=Aphidius) testaceipes

23. The leaf and/or stem of plant swells, like a lump; due to the parasitism by an insect.

24. Wasps, flies, aphids or other insects "trick" the plant into making a house for the insect to live in while it matures. The insect tells the plant to build it a home, then the insect lives in the home - often while it is feeding upon the plant!

25. In this photograph, the reddish clump on the left side of the tree is mistletoe. It is growing on a paloverde tree. Although it makes all of its own food, the mistletoe's root-like parts get water through the paloverde branches and not directly from the soil.

26. A fly agaric mushroom (Amanita muscaria) and a cone of Eastern White Pine are side by side on a New Hampshire forest floor in October. A sapling of Eastern Hemlock sends sprays over the mushroom, and wintergreen adds a splash of red. The pine and fungus form a partnership in which underground filaments of the mycorrhizal fungus invade the roots of the pine, and both provide essential nutrients to each other. Both partners have their reproductive structures above ground.