Population biology of mushroom forming fungi (Agaricomycetes) is not well understood. Furtheremore, there are some important open questions regarding basic aspects of the biology of these fungi that have deep implications for the study of their population biology, such as reported mutation rates that are, in different species and systems, orders of magnitude both larger and smaller than most other biological systems. MUSHEUM aims to fill knowledge gaps by using museum specimens collected across a century in Norway to understand how the gene pool has changed over time. DNA will be extracted fromdried samples of two species of wood decay mushrooms, Trichaptum abietinum and Phellopilus nigrolimitatus. Trichaptum is a common, widespread, short lived, and early colonizing mushroom whose population biology has been characterized at global scale. Phellopilus, on the other hand, is long lived, restricted to Northern Europe, mainly associated with well preserved forests and red listed species. We hypothesize that the differences in lifestyle in these two species will be reflected in their gene pool and its change over the XXth century. In the case of Trichaptum, different genetic lineages exist in Norway, likely derived from different routes of post glacial colonization and apparently distributed according to climatic preferences. These climatic prefereces mean that the distribution of these two population might have changed in the past in response to climate change. As Norway is disproportionally affected by climate change, the project will help understand its effects in mushrooms forming fungi, which represent a poorly studied but key component of nutrient cycling and carbon cycles in terrestrial ecosystems. Meanwhile, Phelopillus has been affected by post WW2 forestry policies in Norway, with populations shrinking. Providing a historical perspective will help evaluate the impact of these threats on a mushroom species, a group traditionally neglected in conservation policies.
