Commensalism or Mutualism?

While searching for food, coyotes prefer the company of badgers that are efficient in digging out animals from their burrows. Badgers are not fast runners, while coyotes are. The two get together while chasing for food and coyotes benefit from the badgers' digging abilities. It is unclear whether badgers derive any advantage from coyotes, thus making it difficult to say whether their relationship is that of mutualism or commensalism.

Eastern Chipmunk and Oak Tree: The eastern chipmunk has a mutualistic relationship with the oak tree. The chipmunk takes shelter from the tree. Staying on these trees help it seek protection from predators. It takes seeds from the tree and disperses them, thus benefiting the tree too. Birds and Deer: Deer allow the birds to eat bugs off their fur. In this way, the deer can get rid of the insects on their bodies, while the birds derive their food from them. Ants and Plant Thorns: Ants in the deciduous forest nest inside the plants' thorns to take food and shelter from them. In turn, the ants protect the plants from attack by herbivores. Morels and Plants: Morels attach to the roots of plants to derive nutrition from them. Due to the attachment, the absorption capacities of the plant increase. Thus, even the plant benefits from the relationship.

Red Squirrels and Oak Tree: Another example of symbiosis in the deciduous forest is that of red squirrels and oak trees. The squirrel receives shelter and food from the oak tree. The oak tree is neither harmed nor benefited from this relationship. Moss and Oak Tree: Moss thrives on the barks of oak trees. The oak tree is unaffected while the moss is saved from choking due to the leaf litter. Here again, the moss is benefiting without harming the oak tree. Pseudoscorpions and Trees: Pseudoscorpions eat mites under the trees. Thus, they derive food with the help of the trees, without benefiting or harming them. Racoons/Owls and Trees: Racoons and owls live in the trees for shelter and the tree is neither harmed nor benefited. Insects and Trees: Some insects have developed to look like twigs or leaves. This makes it difficult for the predators to spot them. This benefits the insects and the tree is not harmed.

White-tailed Deer and Ticks: A classic example of parasitism in the deciduous forest would be the relationship between a tick and a white-tailed deer. The tick stays and feeds on the nutrients in the deer. In this process, the deer may get an infectious disease from the tick. The tick sucks in nutrients from the deer and harms it. American Beech Tree and Beech Drops: Another example of a parasitic relationship would be that between the American beech tree and a plant called beech drops. Beech drops solely grow under beech trees. They lack chlorophyll. They live wholly on the sap of the beech tree. The beech drops have a special root structure known as a haustorium which helps them adhere to the host plant. Laetiporus Cincinnatus and Oak Tree: The fungus Laetiporus cincinnatus and oak trees share a parasitic relationship. The fungus sucks in nutrients form the oak tree because of which the oak tree does not get all the nutrients it needs. Chicken of the Woods and Trees: The fungus chicken of the woods grows on trees and harms them by taking all their nutrients. Mistletoe and Mangrove Tree: The mistletoe grows on mangrove trees. It penetrates through the bark of the tree and takes in nutrients, thus weakening the mangrove tree. Catalpa Hornworm and Cotesia Congregata: The wasp Cotesia congregata injects its eggs into the body of the caterpillar catalpa hornworm with the help of a long sting-like ovipositor. The wasps may also lay eggs on the leaves which are eaten by the caterpillar. These eggs grow into larvae which feed inside the caterpillar. When the wasp grubs grow, they break out through the skin of the larvae and form cocoons. The caterpillar then dies. A few days after that, adult wasps come out of the cocoons and search for another caterpillar to parasitize. Sycamore Lace Bug and Sycamore: The bugs adhere to the leaves of the sycamore to suck out juices from it. Oak Treehoppers and Oak Tree: The treehoppers suck out sap from the oak tree. Indian Pipes and Mycorrhizae: The Indian Pipes plant lacks chlorophyll and cannot produce food on its own. It taps into the mycorrhizae and derives carbohydrates from them. The mycorrhizae get carbohydrates from their photosynthesizing plant partner. Squawroot and Oak Tree: The squawroot is a flowering plant that gets its energy by tapping into the oak's roots. Bobcat and Tapeworm: The tapeworm lives inside the bobcat and gets its nutrition. The bobcat is harmed in this association.

Mountain Lion and Caribou: In a predator-prey relationship, one member is a prey and the other member is the predator. An example of this relationship would be a mountain lion preying on a caribou. Bobcat and Deer: Bobcat, the predator feeds on deer and small rodents. Owls and Birds: An owl feeds on rodents and other small birds. Skunks and Insects: Skunks feed on insects and by using their anal scent glands, defend themselves against predators. Opossum and Insects/Birds/Frogs/Snakes: Opossum feeds on insects, frogs, birds, snakes, small mammals, slugs, and earthworms. To defend themselves, they act as a dead or sick animal. They hiss at their target if they feel threatened. Mountain Lions and White-Tailed Deer: Mountain lions are the predators and the white-tailed deer are their prey. Dog-day Cicada and Cicada-Killer Wasp: Dog-day cicada are preyed on by cicada-killer wasps. These wasps can sting and paralyze a cicada. They fly it home to their burrow and bury it with an egg on it. The egg hatches and the larva of the wasp eats the flesh of the cicada. Copperheads and Rodents: Copperheads, the predators, eat rodents, their prey. Red-Shouldered Hawk and Lizards/Insects/Rodents: The hawk preys on lizards, insects, and various rodents. Hawk and Squirrel: The hawk is the predator and squirrels are the prey. Eastern Chipmunk and Bald Eagle: The eastern chipmunk is food for the bald eagle.

Cougar and Bear: An example of competition would be the cougar and the bears. Both these animals fight over fish and deer. Kudzu and Trees: The Kudzu competes with trees for sunlight. It grows up the tree trunk to the top to get sunlight for itself. This in turn deprives the trees from the energy intake from sunlight. The Kudzu also sucks energy from it. The tree dies, leaving the Kudzu as the winner. Coyotes and Wolves: Coyotes and wolves eat animals like hares, small birds, and squirrels. They compete for food. Bears and Coyotes: Animals like bears and coyotes compete in temperate deciduous forests for food and territory. Squirrel and Chipmunk: The squirrel and the chipmunk compete for food. They also compete with other animals for resources like nesting sites or mates.

Black Walnut and Other Plants: Black Walnut is an important tree in the deciduous forest. Its leaves and roots secrete hydrojuglone, a chemical, that kills other plants near it.