The Irreversible Loss of a Decomposition Pathway Marks the Single Origin of an Ectomycorrhizal Symbiosis

This research reveals how certain mushroom species permanently lost their ability to decompose dead plant matter as they evolved to form beneficial partnerships with living plants. This evolutionary change represents a point of no return – once these fungi became dependent on their plant partners, they could no longer go back to living independently. Impacts on everyday life: – Helps explain why many forest mushrooms only grow in association with specific trees – Demonstrates how organisms can become permanently dependent on their partners in nature – Provides insights into the evolution of cooperative relationships between species – Improves our understanding of forest ecosystem functioning – Could inform cultivation practices for economically important mushroom species