Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids

Pollinator sharing can offer powerful insights into the floral traits associated with the evolution of a pollination system and the consequences of floral differences for pollinator behaviour. Here, we investigate the first known case of pollinator sharing between two sexually deceptive plant genera...

Full description

Bibliographic Details
Main Authors: Phillips, R., Xu, T., Hutchinson, M., Dixon, Kingsley, Peakall, R.
Format: Journal Article
Published: 2013
Online Access:http://hdl.handle.net/20.500.11937/44407
_version_ 1848756991808241664
author Phillips, R.
Xu, T.
Hutchinson, M.
Dixon, Kingsley
Peakall, R.
author_facet Phillips, R.
Xu, T.
Hutchinson, M.
Dixon, Kingsley
Peakall, R.
author_sort Phillips, R.
building Curtin Institutional Repository
collection Online Access
description Pollinator sharing can offer powerful insights into the floral traits associated with the evolution of a pollination system and the consequences of floral differences for pollinator behaviour. Here, we investigate the first known case of pollinator sharing between two sexually deceptive plant genera. Floral manipulations were used to test the importance of floral traits for pollinator behaviour and pollination efficiency. We also explored the ecological differences enabling species co-occurrence. Drakaea livida and Caladenia pectinata (Orchidaceae) exhibit dramatic differences in floral display and the insectiform appearance of the labellum, yet both are pollinated by sexually attracted males of the thynnine wasp Zaspilothynnis nigripes. Because of the prevalence of cryptic species in some genera of thynnine wasps, we confirmed pollinator sharing by a mark-recapture study and sequencing of the mtDNA CO1 region. Floral dissections revealed that semiochemicals used to attract the pollinator are released from the labellum in D. livida and sepaline clubs in C. pectinata. Drakaea livida was more efficient at converting pollinator attraction into potential pollen deposition leading to higher fruit set. Floral manipulations showed that pollinator contact with the labellum increases when it is the point of semiochemical release. However, sexual attraction to the labellum remained infrequent in C. pectinata in all experimental treatments. While their distribution and climatic range show extensive overlap, the differences in edaphic requirements of the two orchid species suggest that they rarely co-occur. Therefore, the potential cost of sharing the same pollinator species is not realized. Synthesis. This case of pollinator sharing confirms that morphological traits do not place a strong constraint on the evolution of sexual deception. However, interspecific differences in floral traits have important consequences for converting attraction into pollination, suggesting that selection can act to increase efficiency at multiple steps of the pollination process. This system provides a novel opportunity to elucidate the chemical, visual and morphological adaptations underpinning the evolution of sexual mimicry. Synthesis. This case of pollinator sharing confirms that morphological traits do not place a strong constraint on the evolution of sexual deception. However, interspecific differences in floral traits have important consequences for converting attraction into pollination, suggesting that selection can act to increase efficiency at multiple steps of the pollination process. This system provides a novel opportunity to elucidate the chemical, visual and morphological adaptations underpinning the evolution of sexual mimicry.
first_indexed 2025-11-14T09:21:00Z
format Journal Article
id curtin-20.500.11937-44407
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T09:21:00Z
publishDate 2013
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-444072017-09-13T14:10:11Z Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids Phillips, R. Xu, T. Hutchinson, M. Dixon, Kingsley Peakall, R. Pollinator sharing can offer powerful insights into the floral traits associated with the evolution of a pollination system and the consequences of floral differences for pollinator behaviour. Here, we investigate the first known case of pollinator sharing between two sexually deceptive plant genera. Floral manipulations were used to test the importance of floral traits for pollinator behaviour and pollination efficiency. We also explored the ecological differences enabling species co-occurrence. Drakaea livida and Caladenia pectinata (Orchidaceae) exhibit dramatic differences in floral display and the insectiform appearance of the labellum, yet both are pollinated by sexually attracted males of the thynnine wasp Zaspilothynnis nigripes. Because of the prevalence of cryptic species in some genera of thynnine wasps, we confirmed pollinator sharing by a mark-recapture study and sequencing of the mtDNA CO1 region. Floral dissections revealed that semiochemicals used to attract the pollinator are released from the labellum in D. livida and sepaline clubs in C. pectinata. Drakaea livida was more efficient at converting pollinator attraction into potential pollen deposition leading to higher fruit set. Floral manipulations showed that pollinator contact with the labellum increases when it is the point of semiochemical release. However, sexual attraction to the labellum remained infrequent in C. pectinata in all experimental treatments. While their distribution and climatic range show extensive overlap, the differences in edaphic requirements of the two orchid species suggest that they rarely co-occur. Therefore, the potential cost of sharing the same pollinator species is not realized. Synthesis. This case of pollinator sharing confirms that morphological traits do not place a strong constraint on the evolution of sexual deception. However, interspecific differences in floral traits have important consequences for converting attraction into pollination, suggesting that selection can act to increase efficiency at multiple steps of the pollination process. This system provides a novel opportunity to elucidate the chemical, visual and morphological adaptations underpinning the evolution of sexual mimicry. Synthesis. This case of pollinator sharing confirms that morphological traits do not place a strong constraint on the evolution of sexual deception. However, interspecific differences in floral traits have important consequences for converting attraction into pollination, suggesting that selection can act to increase efficiency at multiple steps of the pollination process. This system provides a novel opportunity to elucidate the chemical, visual and morphological adaptations underpinning the evolution of sexual mimicry. 2013 Journal Article http://hdl.handle.net/20.500.11937/44407 10.1111/1365-2745.12068 unknown
spellingShingle Phillips, R.
Xu, T.
Hutchinson, M.
Dixon, Kingsley
Peakall, R.
Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids
title Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids
title_full Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids
title_fullStr Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids
title_full_unstemmed Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids
title_short Convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids
title_sort convergent specialization - the sharing of pollinators by sympatric genera of sexually deceptive orchids
url http://hdl.handle.net/20.500.11937/44407