Lichens, the primary producer in the tundra biome, exemplify symbiosis as they are actually a blend of a fungus and an alga which support one another. The fungus provides water for both, and the alga provides the food.Continue Reading
Through photosynthesis, the alga turns water, light and carbon dioxide into glucose for itself and the fungus. The fungus holds onto water in its liquid state for the two organisms so that neither dehydrates. The fungus forms an attachment with the substrate rock below them, allowing them to thrive in an area where almost nothing else would.
Frequently, these lichens thrive right on top of a bare, rocky surface, living off sunlight and condensation. The alga would not be able to absorb water independently, and the fungus does not have an independent mechanism to convert light and carbon dioxide into food, and so the fungus would starve to death.
In parts of the tundra biome that feature enough water, other plants grow that do not live symbiotically, such as grasses, moss and liverworts. This greater variety in plants allows herbivorous animals, such as reindeer, to subsist throughout the long periods of winter. The symbiotic lichens, though, have the greatest distribution throughout the tundra.Learn more about Biology