Hermit crabs find shells left by snails that have died and move in.
Human intestines provide food for bacteria that live inside the digestive system.
Kudzu vines grow by climbing and wrapping around trees.
Fungi form lichens by living in a close relationship with an algae. The fungus provides a protective home for the algae and gathers mineral nutrients from rainwater and from dissolving the rock underneath.
Hummingbirds feed on nectar from flowers.
Honeyguide birds find a bee hive, then chatter loudly to attract the Honey badger. They fly toward the hive, making sure the badger is following.
Mycorrhizal fungi invade and live in or among root cells of many plants. the plant provides nutrients to the fungi.
Ticks live on dogs and fed on their blood and tissues.
Skunks often live in burrows that have been dug and abandoned by woodchucks.
Athlete's foot fungus lives on the skin of humans and feeds on keratin, a protein.
Skunkcabbage plants attract flies in cool weather by making heat and provide food to the flies that come.
Remora use suckers to attach temporarily to large marine animals such as sharks, manta rays, whales, turtles, or large fish.
Snapping shrimp have poor vision and depend on their goby fish roommate to give the danger signal when predators come and guide them back home if they wander too far.
Red-chested cuckoo birds find an unattended robin nest, push out the robin eggs, and lay their eggs in the robin's nest, and leave.
Gall insects lays their eggs in the leaves or branches of Oak trees, causing a lump to form.
The shark provides free transportation, protection, and dropped food and feces which the remora feeds on. The host is not injured.
Oak trees provide shelter and food to the insect larvae, but are not harmed.
Snails die and leave behind their shells.
Upon arrival at the bee hive, the badger tears open the hive and feasts on the honey. Then the Honeyguide bird feeds on the remaining wax and larvae.
Goby fish who don't have a place to hide are quickly eaten. They find a snapping shrimp roommate who digs a hole for both to live in.
Dogs get skin irritation and can pick up diseases carried by ticks.
Beneficial bacteria live in the intestines of humans and help digest cellulose from plants that humans don’t have the enzymes to break down.
Woodchucks abandon holes which are later used by skunks.
The algae gathers energy from the sun using photosynthesis. Both the algae and fungus share their nutrients with each other.
Robin babies die and robin parents feed and take care of the cuckoo babies.
Kudzu covered trees die as they are smothered and break under the weight of the growing Kudzu vines
Flies move from one skunkcabbage plant to the next, feeding and transferring pollen as they go.
The mycorrhizal fungi help the host plant absorb inorganic nitrogen and phosphorus from the soil. Some mycorrhizal fungi also secrete antibiotics which may help protect their host from invasion by parasitic fungi and bacteria.
Humans have itchy, cracked skin which can become infected.
Flowers are pollinated by hummingbirds as they move from flower to flower.
