Macroevolutionary dynamics of nectar spurs, a key evolutionary innovation.

@article{FernndezMazuecos2019MacroevolutionaryDO,
  title={Macroevolutionary dynamics of nectar spurs, a key evolutionary innovation.},
  author={Mario Fern{\'a}ndez‐Mazuecos and Jos{\'e} Luis Blanco‐Pastor and Ana Juan and Pau Carnicero and Alan Forrest and Marisa Alarc{\'o}n and Pablo Vargas and Beverley J. Glover},
  journal={The New phytologist},
  year={2019},
  volume={222 2},
  pages={
          1123-1138
        }
}
Floral nectar spurs are widely considered a key innovation promoting diversification in angiosperms by means of pollinator shifts. We investigated the macroevolutionary dynamics of nectar spurs in the tribe Antirrhineae (Plantaginaceae), which contains 29 genera and 300-400 species (70-80% spurred). The effect of nectar spurs on diversification was tested, with special focus on Linaria, the genus with the highest number of species. We generated the most comprehensive phylogeny of Antirrhineae… 

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References

SHOWING 1-10 OF 115 REFERENCES
THE DIVERSIFICATION OF HALENIA (GENTIANACEAE): ECOLOGICAL OPPORTUNITY VERSUS KEY INNOVATION
TLDR
It is shown that Halenia originated in East Asia and migrated via North America into Central America, and from there, it colonized South America three times independently, probably within the last million years.
Floral Nectar Spurs and Diversification
  • S. Hodges
  • Biology
    International Journal of Plant Sciences
  • 1997
TLDR
The data indicating that the evolution of floral nectar spurs represents a key innovation in Aquilegia and many additional groups are reviewed, providing strong support for the key innovation hypothesis.
Corolla morphology influences diversification rates in bifid toadflaxes (Linaria sect. Versicolores).
TLDR
It is confirmed that different forms of floral specialization can lead to dissimilar evolutionary success in terms of diversification and suggested that opposing individual-level and species-level selection pressures may have driven the evolution of pollinator-restrictive traits in bifid toadflaxes.
Evolution of nectar spur length in a clade of Linaria reflects changes in cell division rather than in cell expansion
TLDR
It is found that changes in cell number and therefore in cell division largely explain evolution of spur length, which contrasts with previous studies in Aquilegia which have found that variation in nectar spur length is due to directed cell expansion over variable time frames.
Spurring plant diversification: are floral nectar spurs a key innovation?
  • S. Hodges, M. Arnold
  • Biology
    Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 1995
TLDR
It is shown that patterns of diversification within and among clades that have evolved floral nectar spurs strongly support the hypothesis that floral n dessert spurs represent a key innovation.
Pollinator shifts drive increasingly long nectar spurs in columbine flowers
TLDR
Using a species-level phylogeny of the columbine genus, Aquilegia, a significant evolutionary trend for increasing spur length during directional shifts to pollinators with longer tongues is shown and evidence for ‘punctuated’ change in Spur length during speciation events is found, suggesting that AquileGia nectar spurs rapidly evolve to fit adaptive peaks predefined by pollinator morphology.
Spurring plant diversification : Are floral nectar spurs a key innovation ?
TLDR
This work considers whether ancestral reconstruction of continuous traits should reflect an underlying evolutionary model of the process that describes or dictates trait evolution, and how traits may be transformed to better meet an appropriate distribution.
Seed size and its rate of evolution correlate with species diversification across angiosperms
TLDR
It is shown that absolute seed size and the rate of change in seed size are both associated with variation in diversification rates, and that smaller-seeded plants had higher rates of diversification, possibly due to improved colonisation potential.
PHYLOGENETIC ANALYSIS OF TRAIT EVOLUTION AND SPECIES DIVERSITY VARIATION AMONG ANGIOSPERM FAMILIES
TLDR
A molecular phylogeny of the angiosperm families is used to reanalyse correlations between S and family‐level traits and use reconstructions of trait evolution to interpret the results and confirm that pollination mode and growth form are correlated with S.
...
1
2
3
4
5
...