Evolutionary constraints and adaptation shape the size and colour of rain forest fruits and flowers at continental scale

Aim: Large-scale patterns in flower and fruit traits provide critical insights into selection processes and the evolutionary history of plant lineages. To isolate and identify the role of selective pressures including different plant-animal interactions, and the factors driving trait evolution, we investigate convergence and divergence between flower and fruit traits in shared environments. Location: Australia to Southeast Asia. Time period: Eocene (~45 My) to Present. Major taxa studied: Woody angiosperm rainforest species (2248 species, 133 families). Methods: Using a continental scale data set for all woody angiosperm species in the Australian rainforest (1816 free-standing and 432 climbing species) we compare the colour and size of fleshy fruits and flowers in relation to life form (trees/shrubs and vines), species biogeographic histories and origins (Sunda vs. Sahul), and bio-regional distributions. Results: Fleshy fruits in the Australian rainforest are mostly small, with a diversity of colours (<30mm; 81%), while flowers are mostly small (<10mm; 65%) and whitish (~80%). Compared to trees and shrubs, climbing species showed a higher proportion of red fleshy fruits, and large coloured flowers. Small whitish flowers were dominant across lineages from different biogeographic origins (Sunda-Sahul) and geographical regions, while both small and large fleshy fruits retained a range of disperser attractant colours. Main conclusions: Continental scale size and colour characteristics of flowers and fleshy fruits differed despite sharing environments with similar abiotic selective pressures through time. Plant-animal interactions including pollination and dispersal likely mediate different evolutionary outcomes for plant traits, and reflect both adaptation and evolutionary constraints.

Usage Notes

The data file comprises flower and fruit traits, ancestry allocation, and distribution in regions of 2248 Australian angiosperm rainforest species (free-standing and climbing species). Flower colour and size was compiled for 2237 species (database_flower=1). Fleshy fruit colour and size was compiled for 1125 species (database_fleshy_fruit=1). The original trait data were compiled by Robert Kooyman (RBGSyd; Macquarie University) while Chloé Delmas (INRAE) added fruit and flower colour fields. Find trait description in the ReadMe file associated and more details in the paper "Evolutionary constraints and adaptation shape the size and colour of rainforest fruits and flowers at continental scale" Delmas et al. 2020.