Wednesday, 8 April 2015

Number of fungal species “overestimated”

The estimated global species richness of fungi has long been estimated as 1.5–5.1 million species.  However, this could, according to new research, be a vast overestimation.

University of Tartu Natural History Museum examined various geographic areas. The scientists examined 15,000 soil samples. From DNA sequencing of the collected samples, using new generation sequencing methods, the researchers found around 45,000 fungal species.

It was found that climatic factors, followed by edaphic and spatial patterning, are the best predictors of soil fungal richness and community composition at the global scale. Richness of all fungi and functional groups is causally unrelated to plant diversity, with the exception of ectomycorrhizal root symbionts, suggesting that plant-soil feedbacks do not influence the diversity of soil fungi at the global scale. The plant-to-fungi richness ratio declined exponentially toward the poles, indicating that current predictions—assuming globally constant ratios—overestimate fungal richness by 1.5- to 2.5-fold. Fungi follow similar biogeographic patterns as plants and animals, with the exception of several major taxonomic and functional groups that run counter to overall patterns. Strong biogeographic links among distant continents reflect relatively efficient long-distance dispersal compared with macro-organisms.

For further details, see:

L. Tedersoo, M. Bahram, S. Polme, et al Global diversity and geography of soil fungi. Science, 2014; 346 (6213): 1256688 DOI: 10.1126/science.1256688

Posted by Tim Sandle