Did Pollination Shifts Drive Diversification in Southern African Gladiolus? Evaluating the Model of Pollinator-Driven Speciation

@article{Valente2012DidPS,
  title={Did Pollination Shifts Drive Diversification in Southern African Gladiolus? Evaluating the Model of Pollinator-Driven Speciation},
  author={Luis Valente and John C. Manning and Peter Goldblatt and Pablo Vargas},
  journal={The American Naturalist},
  year={2012},
  volume={180},
  pages={83 - 98}
}
The pollinator-driven ecological speciation model has frequently been invoked to explain plant richness in biodiversity hotspots. Here, by focusing on Gladiolus (260 species), a flagship example of a clade with diverse pollination biology, we test the hypothesis that high species diversity in southern Africa, one of the world’s most floristically rich regions, has primarily been driven by ecological shifts in pollination systems. We use phylogenetic methods to estimate rates of transition… 

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References

SHOWING 1-10 OF 55 REFERENCES
The pollination niche and its role in the diversification and maintenance of the southern African flora
  • Steven D. Johnson
  • Biology, Medicine
    Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2010
TLDR
The evidence that disturbance provokes pollination failure in some southern African plants with specialized pollination systems is considered, to consider the risk of plant extinction.
The Role of Pollinator Shifts in the Floral Diversification of Iochroma (Solanaceae)
TLDR
It is found that nonphylogenetic models typically fit the data better than phylogenetic models (Brownian motion, Ornstein–Uhlenbeck, and thus results varied little across trees), and species with high nectar reward and large displays are significantly more likely to be pollinated by hummingbirds and less likely toBe pollination by all groups of insects.
The Role of Animal Pollination in Plant Speciation: Integrating Ecology, Geography, and Genetics
TLDR
It is concluded that floral isolation is rarely, if ever, sufficient to cause speciation on its own, but that it acts synergistically with other isolating mechanisms.
Phylogeny and radiation of pollination systems in DISA (Orchidaceae).
TLDR
The patterns of adaptive radiation in Disa, a large orchid genus in southern Africa, suggest that a few dominant pollinator species in a region may be sufficient to generate diversification in plants through repeated floral shifts that never retrace the same pathways.
MACROEVOLUTIONARY DATA SUGGEST A ROLE FOR REINFORCEMENT IN POLLINATION SYSTEM SHIFTS
TLDR
Comparative analysis of sister-species pairs of Geraniaceae, Iridaceae, and Orchidaceae showed that for sister species with overlapping distribution ranges, pollination system shifts are significantly associated with edaphic shifts, and for allopatric sister species, there is no significant association.
EVOLUTION AND COEXISTENCE OF POLLINATION ECOTYPES IN AN AFRICAN GLADIOLUS (IRIDACEAE)
TLDR
Positive directional selection on tube length was found to occur in both morphs of the African iris Gladiolus longicollis, a trait that could be used as a cue for morph‐specific foraging by hawkmoths.
Is Floral Specialization an Evolutionary Dead-End? Pollination System Transitions in Ruellia (Acanthaceae)
  • E. Tripp, P. Manos
  • Biology, Medicine
    Evolution; international journal of organic evolution
  • 2008
TLDR
Evidence for multiple reverse transitions from presumed ancestral hummingbird pollination to more derived bee or insect pollination is found and is consistent with the hypothesis that some transitions have been adaptive in the evolution of Ruellia.
Pollination, adaptation and speciation models in the Cape flora of South Africa
Recent species definitions have placed emphasis on "diagnostic characters" rather than isolating mechanisms. Such characters can be informative about the evolutionary processes which lead to
The Effects of Above- and Belowground Mutualisms on Orchid Speciation and Coexistence
TLDR
The results demonstrate that the two dominant mutualisms in terrestrial ecosystems can play major but contrasting roles in plant community assembly and speciation.
Ancestral reconstruction of flower morphology and pollination systems in Schizanthus (Solanaceae).
TLDR
Results suggest that diversification of flower traits in Schizanthus has occurred in relation to pollinator shifts, and suggest that the moth syndrome evolved in the ancestor of three species that inhabit the Atacama Desert.
...
1
2
3
4
5
...