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Abstract The colours of fleshy fruits play a critical role in plant dispersal by advertising ripe fruits to consumers. Fruit colours have long been classified into syndromes attributed to selection by animal dispersers, despite weak evidence for this hypothesis. Here, we test the relative importance of biotic (bird and mammal frugivory) and abiotic (wet season temperatures, growing season length and UV‐B radiation) factors in determining fruit colour syndrome in 3163 species of fleshy‐fruited plants. We find that both dispersers and environment are important, and they interact. In warm areas, contrastive, bird‐associated fruit colours increase withrelative bird frugivore prevalence, whereas in cold places these colours dominate even where mammalian dispersers are prevalent. We present near‐global maps of predicted fruit colour syndrome based on our species‐level model and our newly developed characterisations of relative importance of bird and mammal frugivores.
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Why is fruit colour so variable? Phylogenetic analyses reveal relationships between fruit‐colour evolution, biogeography and diversification
Abstract AimAre different fruit colours related to large‐scale patterns of dispersal, distribution and diversification? Here, we investigate this question for the first time, using phylogenetic approaches in the tribe Gaultherieae (Ericaceae). We test relationships between fruit colour and (a) biogeographic dispersal, (b) elevational and latitudinal species distributions and (c) rates of diversification. LocationGlobal. Time periodRecent to 30 million years ago. Major taxa studiedThe plant tribe Gaultherieae in the family Ericaceae (blueberries and relatives). MethodsWe estimated a new time‐calibrated phylogeny for Gaultherieae. Data on fruit colours and geographic distributions for each species were compiled from published sources and field observations. Using phylogenetic methods, we estimated major dispersal events across the tree and the most likely fruit colour associated with each dispersal event, and tested whether dispersal between major biogeographic regions was equally likely for different fruit colours, and whether dispersal distances were larger for certain colours. We then tested the relationships between fruit colours and geographic variables (latitude, elevation) and diversification rates. ResultsLarge‐scale dispersal events were significantly associated with red‐fruited lineages, even though red‐fruited species were relatively uncommon. Further, different fruit colours were associated with different elevations and latitudes (e.g. red at lower elevations, violet at lower latitudes, white at higher elevations). Violet colour was related to increased diversification rates, leading to more violet‐fruited species globally. Main conclusionsOverall, we show that different fruit colours can significantly impact the large‐scale dispersal, distribution and diversification of plant clades. Furthermore, the interplay between biogeography and fruit‐colour evolution seems to generate “taxon cycles” in fruit colour that may drive variation in fruit colour over macroevolutionary time‐scales.
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- Award ID(s):
- 1655690
- PAR ID:
- 10461136
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Ecology and Biogeography
- Volume:
- 28
- Issue:
- 7
- ISSN:
- 1466-822X
- Format(s):
- Medium: X Size: p. 891-903
- Size(s):
- p. 891-903
- Sponsoring Org:
- National Science Foundation
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