The red-backed vole is usually able to derive nutrients from the spores of the fungi it eats. The presence of rotting logs on a forest floor can have beneficial effects on the trees around them. The spores of certain fungi cannot remain viable above the ground but must be deposited near the roots of trees. Dead and decaying trees are the ideal environment for the growth of certain fungi.
Dead, rotting logs on the forest floor provide the habitat for a small mammal, the red-backed vole, which subsists almost entirely on the portion of certain specialized fungi which grows aboveground. The fungi-spores are deposited on the forest floor by the voles. Some of the fungi that develop from these spores form underground sheaths around the fine roots of growing trees, and assist the trees by processing and sharing nutrients and producing an antibiotic which protects the trees from disease.
The information above provides the most support for which one of the following conclusions?