Symbiosis is a term scientists use to describe animals and plants living together. Over time species have found ways of working together, or using one another to get ahead. The three types of symbiosis are mutualism, commensalism and parasitism. Throughout the animal kingdom examples can be found.
This type of symbiosis benefits both of the animals it involves.
-One interesting case of mutualism is that of the ants and their aphid "cows". This relationship benefits ants with food and aphids with safety. Ants stroke the aphids to get them to release the honeydew that they feed to their offspring. To protect their honeydew makers the ants then herd them, guard them and sometimes even bring them into their tunnels for the night! The aphids are safe and warm no matter the weather, protected by the ant farmers.
-Oxpeckers and African buffalo. These birds cry out to warn the buffalo of approaching danger. Oxpeckers are also fed by the ticks preying on the herd animals. They get plenty of food and their host gets to keep clean, healthy and safe.
-Polyps and hermit crabs are an odd couple on the sea floor. Hermit crabs roam around to find food, and polyps normally attach themselves to rock. Sometimes though, the polyp will attach to the hermit crab's shell and over time replace it completely. The hermit crab gets a living shell that grows with it and the polyp gets a wider variety of food as it travels across the reef on its crab mount.
This type of symbiosis benefits one animal and does not effect the other.
-Sharks and remoras. The sharks find meals and the remoras travel with them, eating scraps from the surrounding water. Remoras get easy meals and the shark is not affected.
- A species of barnacle only grows on the jaws of whales. They feed from plankton as they travel through the ocean. The whale does not benefit but is not harmed either.
This type of symbiosis benefits one animal and harms the other.
-Ticks, fleas, leeches, bedbugs, and mosquitoes. These are bloodsuckers. They feed off the blood of humans and other mammals. While they usually take relatively small amounts they still cause discomfort and can spread diseases as in the case of mosquitoes and malaria. Enough bloodsuckers feeding on a host can also cause anemia or even death.
-Tapeworms, roundworms, heart-worms are all parasites. They feed on their hosts blood, or the food in their intestines. As a result of these parasites many mammals are weakened and even die.
The Young Oxford Book of Ecology by Michael Scott