The adaptive radiation of lichen-forming Teloschistaceae is associated with sunscreening pigments and a bark-to-rock substrate shift. / Gaya, Ester; Fernández-Brime, Samantha; Vargas, Reinaldo; Lachlan, Robert F.; Gueidan, Cécile; Ramírez-Mejía, Martín; Lutzoni, François.

In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 112, No. 37, 15.09.2015, p. 11600-11605.

Research output: Contribution to journalArticlepeer-review

Published
  • Ester Gaya
  • Samantha Fernández-Brime
  • Reinaldo Vargas
  • Robert F. Lachlan
  • Cécile Gueidan
  • Martín Ramírez-Mejía
  • François Lutzoni

Abstract

Adaptive radiations play key roles in the generation of biodiversity and biological novelty, and therefore understanding the factors that drive them remains one of the most important challenges of evolutionary biology. Although both intrinsic innovations and extrinsic ecological opportunities contribute to diversification bursts, few studies have looked at the synergistic effect of such factors. Here we investigate the Teloschistales (Ascomycota), a group of >1,000 lichenized species with variation in species richness and phenotypic traits that hinted at a potential adaptive radiation. We found evidence for a dramatic increase in diversification rate for one of four families within this order-Teloschistaceae-which occurred ∼100 Mya (Late Cretaceous) and was associated with a switch from bark to rock and from shady to sun-exposed habitats. This adaptation to sunny habitats is likely to have been enabled by a contemporaneous key novel phenotypic innovation: the production in both vegetative structure (thallus) and fruiting body (apothecia) of anthraquinones, secondary metabolites known to protect against UV light. We found that the two ecological factors (sun exposure and rock substrate) and the phenotypic innovation (anthraquinones in the thallus) were all significant when testing for state-dependent shifts in diversification rates, and together they seem likely to be responsible for the success of the Teloschistaceae, one of the largest lichen-forming fungal lineages. Our results support the idea that adaptive radiations are driven not by a single factor or key innovation, but require a serendipitous combination of both intrinsic biotic and extrinsic abiotic and ecological factors.
Original languageEnglish
Pages (from-to)11600-11605
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume112
Issue number37
Early online date31 Aug 2015
DOIs
Publication statusPublished - 15 Sep 2015
This open access research output is licenced under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

ID: 34615609