Mutualism Found in the Tundra

Lichen, a common tundra plant, is a classic example of mutualism.

Mutualism is an interaction between two or more species in which all species benefit. The tundra, being a dry, cold and windy, is a harsh environment in which many species cannot survive at all, and mutualism helps species of the tundra to exploit this vast habitat.

Types

Mutualism can be facultative or obligate. Facultative mutualism is optional for the species involved and may only occur when conditions favor it. Obligate mutualism is not optional. Instead, the two species have co-evolved to the point that one cannot survive without the other.

Function

The benefits to each species vary with every species pair. In the most famous example of tundra mutualism, lichen plants are composed of a fungus, which grips rock surfaces tightly and collects water and salts, protecting algae cells, which photosynthesize to provide sugar and oxygen to the fungus. Another type of mutualism is that between reindeer and the microorganisms that live in their digestive tract. The microorganisms receive food from the reindeer, and transform the food into a form usable by the reindeer.

Effects

Mutualism improves the reproductive success of participating species, which in turn promotes more mutualism in subsequent generations.

References

• "General Ecology;" D. T. Krohne; 1998
• Dictionary.com: Mutualistic
• The Open Door Website: Mutualistic Relationships