Multiple shifts to different pollinators fuelled rapid diversification in sexually deceptive <i>Ophrys</i> orchids

Breitkopf, Hendrik; Onstein, Renske E.; Cafasso, Donata; Schlüter, Philipp M.; Cozzolino, Salvatore

doi:10.1111/nph.13219

Cited by 102 publications

(178 citation statements)

References 95 publications

Supporting

Mentioning

166

Contrasting

Unclassified

Order By: Relevance

“…It regularly occurs in sympatry with the geographically widespread O. insectifera . A time‐calibrated maximum clade credibility tree (Breitkopf et al., 2015) supports a very recent divergence between Ophrys insectifera and Ophrys aymoninii (i.e., in the last 500,000 years). Our study was performed in the Parc Naturel Régional des Grands‐Causses in Aveyron, France during May/June 2010–2013 where the two species flower simultaneously.…”

Section: Methodssupporting

confidence: 53%

“…Results found here mirror those already found by Breitkopf et al. (2015) in all terminal clades of their Ophrys phylogenetic analysis and point toward an incomplete lineage sorting scenario as consequence of very recent radiation of species groups in this genus.…”

Section: Resultsmentioning

confidence: 96%

“…Moreover, this study indicates that female reproductive success was negatively associated with density and that few scent compounds can induce—at least occasional—copulation attempts by a new pollinator. However, for a better understanding of speciation scenarios in sexual mimics, a better resolved phylogenetic framework is desirable, to confidently assign recently diverged pairs of sister species within the flock of genetically often very similar species (Breitkopf et al., 2015). Furthermore, in our specific study system, a better understanding of the chemical ecology of the pollinator of O. insectifera is needed to predict its behavioral responses to variation in floral scent.…”

Section: Resultsmentioning

confidence: 99%

“…(2015) for 18 Ophrys specimens belonging to the O. insectifera lineage (namely 3 O. aymoninii , 3 O. subinsectifera , and 12 O. insectifera ) plus one accession of O. garganica used as outgroup. The combined alignment was analyzed using Bayesian inference (MrBayes v.3.1.2), with the un‐partitioned dataset and by employing the GTR+Γ model of molecular evolution according to Breitkopf et al.…”

Section: Methodsmentioning

confidence: 99%

“…The combined alignment was analyzed using Bayesian inference (MrBayes v.3.1.2), with the un‐partitioned dataset and by employing the GTR+Γ model of molecular evolution according to Breitkopf et al. (2015). Bayesian analysis was conducted with a single runs of a Markov‐chain Monte Carlo (MCMC) chain for one million generations with tree sampling every 500 generations (CBSU BioHPC, Cornell University).…”

Section: Methodsmentioning

confidence: 99%

See 4 more Smart Citations

Floral scent and species divergence in a pair of sexually deceptive orchids

Gervasi

Selosse

Sauve

et al. 2017

Ecology and Evolution

Self Cite

View full text Add to dashboard Cite

Speciation is typically accompanied by the formation of isolation barriers between lineages. Commonly, reproductive barriers are separated into pre‐ and post‐zygotic mechanisms that can evolve with different speed. In this study, we measured the strength of different reproductive barriers in two closely related, sympatric orchids of the Ophrys insectifera group, namely Ophrys insectifera and Ophrys aymoninii to infer possible mechanisms of speciation. We quantified pre‐ and post‐pollination barriers through observation of pollen flow, by performing artificial inter‐ and intraspecific crosses and analyzing scent bouquets. Additionally, we investigated differences in mycorrhizal fungi as a potential extrinsic factor of post‐zygotic isolation. Our results show that floral isolation mediated by the attraction of different pollinators acts apparently as the sole reproductive barrier between the two orchid species, with later‐acting intrinsic barriers seemingly absent. Also, the two orchids share most of their fungal mycorrhizal partners in sympatry, suggesting little or no importance of mycorrhizal symbiosis in reproductive isolation. Key traits underlying floral isolation were two alkenes and wax ester, present predominantly in the floral scent of O. aymoninii. These compounds, when applied to flowers of O. insectifera, triggered attraction and a copulation attempt of the bee pollinator of O. aymoninii and thus led to the (partial) breakdown of floral isolation. Based on our results, we suggest that adaptation to different pollinators, mediated by floral scent, underlies species isolation in this plant group. Pollinator switches may be promoted by low pollination success of individuals in dense patches of plants, an assumption that we also confirmed in our study.

show abstract

Section: Methodssupporting

confidence: 53%

Section: Resultsmentioning

confidence: 96%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Floral scent and species divergence in a pair of sexually deceptive orchids

Gervasi

Selosse

Sauve

et al. 2017

Ecology and Evolution

Self Cite

View full text Add to dashboard Cite

show abstract

Sexual Deception in Orchids

Rákosy¹

2020

Encyclopedia of Life Sciences

View full text Add to dashboard Cite

Sexual deception has evolved repeatedly within the Orchidaceae. All species exploit the sexual communication system of insects; they rely on a combination of olfactory, visual and tactile signals for tempting mate‐searching males into copulation attempts with their flowers. The exploitation of their pollinator's private communication channel ensures a highly effective pollen transport between conspecific flowers. Despite the elaborate pollination mechanisms deployed by sexually deceptive orchids, their annual reproductive success is notoriously low. This has fuelled intensive research into the evolutionary mechanisms which have given rise to sexual deception. Existing evidence support the hypothesis that these orchids have traded high reproductive output for higher quality seed production. But other factors may also be involved. While their evolution remains shrouded in mystery, their diversification has been revealed to be linked to repeated pollinator shifts mediated by the malleability of their floral traits. Despite decades of research, sexual deception still poses unanswered questions. Key Concepts Sexually deceptive orchids rely on mimicking the chemical, visual and tactile cues used by female insects to attract mate‐searching males. The mimicry is highly accurate, making it difficult for males to distinguish between their conspecific females and the orchid flowers. Sexual deception is a highly specific pollination system; each orchid being usually pollinated by a single pollinator species. The specific pollinator attraction is mediated by the same combination of flower traits in most sexually deceptive species. The sexual pheromone analogue produced by the flowers is thereby the key trait involved in ensuring specific pollinator attraction. Flower colour and morphology can also play a crucial role in pollinator attraction and in ensuring that the pollinators will contact the reproductive structures of the flowers. Despite their elaborate pollination strategies, sexually deceptive orchids are notorious for their low reproductive success. Low fruiting success seems, however, to be compensated by the production of high‐quality seeds through higher outcrossing rates than their food deceptive relatives. It is still debated how and why sexually deceptive orchids evolved from their food‐deceptive ancestors. There are multiple hypotheses which could explain the evolution of sexual deception, but a clear pattern has not yet emerged. Despite their low reproductive success, sexually deceptive orchids seem to be evolutionary highly successful. Their diversification has been linked to repeated pollinator‐shifts driven by often minute changes in their sexual pheromone analogues, followed by subsequent alterations of their flower colour and morphology.

show abstract