Shonali Laha's set of zebra pictures from his Tanzanian Safari in 2002 includes this nice picture of a zebra with oxpeckers on its spine. According to the New England Complex Systems Institute, this is an example of a "symbiotic relationship":
A symbiotic relationship is when two organisms of different species "work together," each benefiting from the relationship. One example of a symbiotic relationship is that of the oxpecker (a kind of bird) and the rhinoceros or zebra. Oxpeckers land on rhinos or zebras and eat ticks and other parasites that live on their skin. The oxpeckers get food and the beasts get pest control. Also, when there is danger, the oxpeckers fly upward and scream a warning, which helps the symbiont (a name for the other partner in a relationship).
