Wolves in a pack usually maintain the dominance order by threats, stares, and other ritualized behaviors rather than fighting, because hurting each other weakens the strength of the whole pack. Staring is a threat for most animal species, and usually enables a more dominant animal to assert authority without outright fighting, thus helping to preserve the species. Because of this, it is advisable to never stare at an animal at the zoo, but staring at a loose dog that's bothering you may encourage it to leave you alone. In social animals, shelter can be individual, thereby increasing competition for resources, or cooperative as in bees. Competition One source of competition in animals is competition for mates, and elaborate courtship rituals have evolved to demonstrate fitness.
Sexual selection is selective pressure by members of the opposite sex.
Plants also have ways of competing with other nearby plants for soil nutrients and water or for access to sunlight. As mentioned above, some plants secrete allopathic chemicals into the soil to inhibit the growth of or kill other nearby plants. Some, such as the previously-mentioned Peppered Moth, use camouflage to hide, while others use mimicry to resemble dangerous or unpalatable species, such as the resemblance between the Locust Borer and a yellowjacket, or the resemblance between Viceroy and Monarch butterflies. Noxious or unpalatable species, such as arrow poison frogs, Monarch butterflies, bees, and ladybugs, actually advertise that fact with warning coloration. Typically these species have stripes or spots of bright red, orange, or yellow with black.