Fire drive plant evolution
Considering fire as evolutionary pressure driving evolution has traditional been neglected, and only now is becoming a topic of research [1-3]. The role of fire as an evolutionary pressure can be elucidated using both macro- and micro-evolutionary approaches. While the micro-evolutionary approach searches for trait divergences in different current selective environments, the macro-evolutionary approach uses dated phylogenies to trace the evolution of traits over long time scales (My). In a previous post  we mentioned an example of the macro-evolutionary approach. In a recent paper, S. Goméz-Gonzalez and collaborators  provided, for the first time, a clear example of the micro-evolutionary approach to demonstrate natural selection driven by fire. They presented compelling evidence that the novel anthropogenic fires affecting the Chilean matorral shaped seed traits on a native annual plants (Helenium aromaticum). By studying populations growing on sites with different recent fire histories, they showed that increasing fire frequency selects for increasing seed pubescence (directional selection): a trait that was proven to be heritable and that increased fitness under experimental heat treatments. This paper was also presented in a special session at the MEDECOS Conference .
Figure: Habitat of Helenium aromaticum in central Chile 
 Pausas, J. G. and D. W. Schwilk. 2012. Fire and plant evolution. New Phytologist 193: [pdf]
 Pausas J.G. 2011. Australia born to burn – phylogenetic evidences. URL: jgpausas.blogs.uv.es, 18/03/2011
 Gómez-González S, Torres-Díaz C, Bustos-Schindler C, Gianoli E, 2011. Anthropogenic fire drives the evolution of seed traits. PNAS 108: 18743-18747. [doi]