Figure 1.
Diversity of functional traits in Ficus subgenus Sycomorus.
a) F. variegata reaches up to 40 m high and is often one of the largest trees in secondary forests (man in photograph ∼ 1.5 m tall (face covered to protect identity)). The cauliflorous figs, borne from small nodes, can just be made out on the trunk. b) F. squamosa, rheophytic (river side) shrub up to 1.5 m high with axial figs (inset). c) F. pseudopalma (inset to scale, the man, who is ∼2 m tall, is holding up a dead leaf) has the second largest leaves in the subgenus and is one of only two monopodial (unbranched) species [15]. d) F. hispida has cauliflorous figs borne on woody branchlets (cauliflorus type (i)). e) F. cereicarpa is a cauliflorous species with very large figs (∼10 cm diameter). This is a male tree, which bears figs around the base of the tree, as is typical of several other species. Older figs, whose wasps have already emerged, can be seen rotting behind and under bunches of newer figs. f) F. ribes has small cauliflorous figs borne on rope-like stolons (cauliflorus type (ii)). F. semicordata: g) a female tree bearing figs at the base of the trunk and h) male figs buried in the soil. For the latter, the leaf litter and soil were scrapped away to reveal the figs. i) Male fig of F. variegata with non-pollinating wasps (Sycophaga sp.) ovipositing through the wall. The brown dots on other figs in the background are bruises resulting from earlier ovipositor insertions. Cauliflorous figs, like this, are often heavily attacked by non-pollinating wasps, which can significantly reduce pollinator production and thus pollen dispersal.
Figure 2.
Phylogeny of Ficus subgenus Sycomorus using maximum likelihood estimation.
The Bayesian topology was similar and we have mapped node support from both analyses (BP/PP). Node support was mapped for nodes with >75 BP or >0.90 PP. Also shown are fruit traits, including fig placement (squares; black = axial, dark grey = cauliflorous type (i), no fill = cauliflorous type (ii), light grey = geocarpic), fig colour (circles; black = red, dark grey = green), and fig diameter (triangles; light grey = <2 cm, dark grey = 2–<4 cm, black = 4+cm), biogeographic distribution (diamonds; light grey = Africa (+Madagascar and Indian Ocean), dark grey = Asia (West of Wallace’s line), black = Pacific (East of Wallace’s line)), and current taxonomy based on morphological characteristics.
Table 1.
Model results of the analysis of fig colour.
Figure 3.
Panel plot of fig size (log transformed) against leaf area (log transformed) by fig placement type.
The y-axis represents the residuals after controlling for phylogenetic auto-correlation (see Methods). Dark grey and light grey points represent species with “red” and “green” mature figs, respectively. Relative to axial figs, cauliflorus type (ii) (est = 8.468±3.2355, t = 2.617, p = 0.01147) and geocarpic (est = 4.237±1.5943, t = 2.658, p = 0.01033) figs were significantly larger, figs on species with larger leaves were significantly larger (est = 0.998±0.1843, t = 5.418, p = 0.000001), and there was a significant negative interaction between fig placement and leaf area for cauliflorous type (i) (est = –1.665±0.5972, t = –2.789, p = 0.00729) and geocarpic (est = −0.816±0.2978, t = –2.739, p = 0.00832) species (Table S3).
Table 2.
Frequency table of frugivory records for 32 Ficus subgenus Sycomorus species.