Data from: Ecology and evolution of the diaspore 'burial syndrome'

Humphreys, Aelys Muriel, University of Zurich

Antonelli, Alexandre, University of Zurich

Pirie, Michael D., University of Zurich

Linder, H. Peter, University of Zurich

Published Nov 24, 2010 on Dryad. https://doi.org/10.5061/dryad.8013

Cite this dataset

Humphreys, Aelys Muriel; Antonelli, Alexandre; Pirie, Michael D.; Linder, H. Peter (2010). Data from: Ecology and evolution of the diaspore 'burial syndrome' [Dataset]. Dryad. https://doi.org/10.5061/dryad.8013

Abstract

Hygroscopically active awns or "bristles" have long intrigued scientists. Experimental evidence shows that they are important for diaspore burial in the correct orientation, thereby increasing successful seed germination and seedling survival. Despite these ecological advantages, 38 of the 280 species of grasses in Danthonioideae lack awns. We provide the first study of awns in a phylogenetic context and show that whilst the awnless state has arisen ca. 25 times independently, the ecological disadvantage of not having an awn also applies in an evolutionary context. Only in Tribolium and Schismus have awnless ancestors diversified to form a clade of primarily awnless descendents. Several of the awnless species in these genera are annual and we find a significant correlation between the evolution of awns and the evolution of life history. A suite of other diaspore traits accompany the awned or awnless states. We interpret the awn as being the visible constituent of a compound "burial syndrome", the two ecological extremes of which may explain the correlation between awns and life history and provide an explanation why awnless species in Tribolium and Schismus persist.

Usage notes

Appendix_I

Character states and callus lengths for each species. The species are the 280 species of Danthonioideae (Poaceae). Characters are awns, lemma indumentum, callus indumentum, callus length and life history. Awns are coded as present (0) or absent (1). Absence of an awn denotes species in which the awn is altogether absent or reduced to a ‘mucro’, i.e. reduced beyond hygroscopic function. Callus and lemma indumentum are coded as villous (0) or glabrous (1), with ‘glabrous’ coded only for those species that never produce hairs on these surfaces. Polymorphic species are coded as (0). Life history was coded as perennial (0) or annual (1). Four species of Pentameris are biannual and these were coded as perennial to distinguish species that survive as adult plants for more than one growing season from those that do not.