Fig. 1.

Water content and relative humidity (RH) experienced by shoots (vegetative shoot + rhizoids with soil) and sporophytes (sporophyte at seta elongation phenophase + shoot + rhizoids with soil) of Aloina ambigua during an experimental drying event (mean ± s.e., n = 3 for each; s.e. values were too small to show on graph for RH; upper dotted line is 50 % RH, lower dotted line is 0·0 % water content). (A) Rapid drying. (B) Slow drying. Trials for RH and water content were independent tests because the occupation of space within the Petri dish by an iButton is significant and may affect water loss. Water content = [shoot mass equilibrated at 50 % RH – d.wt]/d.wt, where d.wt is dry weight. Water content for vegetative shoots with rhizoids removed and equilibrated at 50 % RH = 0·118 ± 0·006 µg H₂O µg d.wt^–1 (n = 6). Water content for sporophytes at early seta elongation phase with rhizoids removed and equilibrated at 50 % RH = 0·130 ± 0·011 µg H₂O µg d.wt^–1 (n = 6).