Some fungi take on different shapes, depending on their environmental conditions. These fungi are called dimorphic fungi , because they have “two forms.” For example, the fungus Histoplasma capsulatum , which causes the disease histoplasmosis, is thermally dimorphic; it has two forms that are dependent on temperature. In temperatures of about 25°C, it grows as a brownish mycelium, and looks like a mass of threads. At body temperature (37°C in humans), it grows as single, round yeast cells.
Consider the following text:
Two mycologists were studying fungi. Max studied regular fungi, while Red studied dimorphic fungi. They were both fascinated by their findings.

Which person learned more about fungi that grows as a brownish mycelium?