Figure 1. Implications of intraspecific variation in root traits for an interspecific Root Economics Space (RES). The graph shows a conceptual diagram of the interspecific RES with the collaboration gradient on the x-axis which ranges from species that rely on their own roots (i.e., the do-it-yourself strategy) to species that depend on mycorrhizal symbiosis (i.e., the outsourcing strategy) for soil resource uptake. The y-axis represents the conservation gradient separating species with root traits that permit poor to strong conservation of plant resources. These two axes are further explained in the main text. Each dot with a black outline represents a given species positioned in the RES depending on its root trait expressions (RD , root diameter; SRL , specific root length; MF %, mycorrhizal colonization rate; RN , root nitrogen concentration; RTD , root tissue density). Dots with the same color but without the black outline represent the same species after it shifted positions within the RES due to intraspecific variation in the corresponding root traits. Numbers in the graph refer to the hypothesized underlying cause of this shift further outlined in the main text.