@article {22011, title = {The long and the short of it: a global analysis of hawkmoth pollination niches and interaction networks}, journal = {Functional Ecology}, volume = {31}, year = {2017}, pages = {101-115}, chapter = {101}, abstract = {

\"1. Proboscis length has been proposed as a key dimension of plant pollination niches, but this niche space has not previously been explored at regional and global scales for any pollination system. Hawkmoths are ideal organisms for exploring pollinator niches as they are important pollinators in most of the biodiverse regions of the earth and vary greatly in proboscis length, with some species having the longest proboscides of all insects.
2. Using data sets for nine biogeographical regions spanning the Old and New World, we ask whether it is possible to identify distinct hawkmoth pollination niches based on the frequency distribution of proboscis length, and whether these niches are reflected in the depths of flowers that are pollinated by hawkmoths. We also investigate the levels of specialization in hawkmoth pollination systems at the regional and community level using data from interaction network studies.
3. We found that most regional hawkmoth assemblages have bimodal or multimodal distributions of proboscis length and that these are matched by similar distributions of floral tube lengths. Hawkmoths, particularly those with longer proboscides, are polyphagous and at the network level show foraging specialization equivalent to or less than that of bees and hummingbirds. In the case of plants, shorter-tubed flowers are usually visited by numerous hawkmoth
species, while those that are longer-tubed tend to exclude shorter-proboscid hawkmoths and thus become ecologically specialized on longer-proboscid hawkmoth species. Longer-tubed flowers tend to have greater nectar rewards, and this promotes short-term constancy by longproboscid hawkmoths.
4. Our results show that pollinator proboscis length is a key niche axis for plants and can account for the patterns of evolution in functional traits such as floral tube length and nectar volume. We also highlight a paradoxical trend for nectar resource niche breadth to increase according to proboscis length of pollinators, while pollinator niche breadth decreases according to the tube length of flowers.\"

}, keywords = {ADAPTATION, ADAPTIVE RADATION, BIOGEOGRAPHY, COEVOLUTION, COMMUNITY STRUCTURE, ECOLOGY, NECTAR SOURCES, POLLINATION, POLLINATOR SHIFT, POLLINATOR SPECIFICITY, SPHINGIDAE}, doi = {10.1111/1365-2435.12753}, author = {Johnson, S.D. and Mor{\'e}, M. and Amorim, F.W. and Haber, W.A. and Frankie, G.W. and Stanley, D.A. and Cocucci, A.A. and Raguso, R.A.} } @article {20949, title = {Angraecum-Orchideen und langr{\"u}sslige Schw{\"a}rmer, Best{\"a}ubung und Evolution}, journal = {Die Orchideen}, volume = {66}, year = {2015}, month = {06/2015}, pages = {175-181}, chapter = {175}, keywords = {ANGRAECUM, COELONIA, COEVOLUTION, ORCHIDACEAE, PANOGENA, POLLINATION, POLLINATOR SHIFT, PREDATION, PREDATOR AVOIDANCE, PROBOSCIS, SPHINGIDAE, SPIDERS, SWING HOVERING, XANTHOPAN}, author = {Wasserthal, L.T.} } @article {20529, title = {Pollinator shifts drive increasingly long nectar spurs in columbine flowers}, journal = {Nature. London}, volume = {447}, year = {2007}, note = {DOI:10.1038/nature05857; two pages of supplementary data online at www.nature.com/nature.; ; ;}, month = {2007}, pages = {706-709}, keywords = {AFLP, AQUILEGIA, BAYESIAN INFERENCE, BOMBUS, COEVOLUTION, DNA, HUMMINGBIRDS, PHYLOGENY, POLLINATION, POLLINATOR SHIFT, POLLINATOR SPECIFICITY, SPHINGIDAE}, author = {Whittall, J. B. and Hodges, S. A.} } @article {20498, title = {Antipredator adaptations in long-tongued hawkmoths and sequential evolution of long-spurred Malagasy {IAngraecum} orchids [Abstract]}, journal = {Zoology. Analysis of Complex Systems}, volume = {101}, year = {1998}, month = {1998}, pages = {34}, keywords = {ADAPTATION, COEVOLUTION, ORCHIDACEAE, POLLINATION, POLLINATOR SHIFT, PREDATOR AVOIDANCE, SPHINGIDAE, SPIDERS}, author = {Wasserthal, L. T.} } @article {20496, title = {The pollinators of the Malagasy Star Orchids Angraecum sesquipedale, A. sororium and A. compactum and the evolution of extremely long spurs by pollinator shift}, journal = {Botanica Acta}, volume = {110}, year = {1997}, month = {1997}, pages = {343-359}, chapter = {343}, abstract = {

\"The pollination process of the extremely long-spurred orchids Angraecum sesquipedale and A. sororium is described and documented here for the first time. The pollinaria and viscidia load was examined in moths captured in central and south Madagascar. Visits to orchids by hawkmoths were rarely observed in the field and were therefore systematically recorded in large flight tents using a night-vision video technique and flashlight photography. Angraecum sesquipedale in Fort Dauphin is pollinated by Xanthopan morgani praedicta and A. sororium on Mt. Angavokely by Coelonia solani. By combining a deep nectar spur of extraordinary length with a protruding labellum functioning as a landing platform, these orchids overcome the moth\&$\#$39;s stereotypic swing-hovering flight thus enabling full insertion of the long tongue. Angraecum compactum in For\êt d\&$\#$39;Ambohitantely is pollinated by both the shorter and longer-tongued forms of Panogena lingens which never swing-hover but is also exploited by X. morgani and C. solani with wastage of pollinaria. The duration of tongue insertion, nectar exploitation and tongue withdrawal were analyzed: legitimate and illegitimate visitors differ in their time budget and approach to the flower. Nectar volume, nectar level and sugar concentration of A. sesquipedale and A. sororium were compared with the nectar requirements of the pollinating hawkmoths. The evolution of very long spurs in these orchids is likely to have involved a series of pollinator shifts. The orchids adapted to different hawkmoth species with increasingly long tongues which primarily evolved to avoid predator attacks during visits to less specialized flowers. This \“pollinator shift\” model modifies the classical \“coevolutionary race\” model. The relevance of the taxon Angraecum bosseri Senghas is questioned.\"

}, keywords = {ANGRAECUM, BEHAVIOUR, COELONIA, COEVOLUTION, ORCHIDACEAE, PANOGENA, POLLINATION, POLLINATOR SHIFT, SPHINGIDAE, XANTHOPAN}, url = {https://doi.org/10.1111/j.1438-8677.1997.tb00650.x}, author = {Wasserthal, L.T.} } @mastersthesis {20126, title = {Long-spurred orchids and their pollinators - an investigation into multiple hypotheses to explain some of Darwin{\textquoteright}s contrivances}, year = {2013}, month = {2013}, pages = {40}, school = {The Open University}, keywords = {ANGRAECUM, COEVOLUTION, DARWIN, DIPTERA, DISA, GLADIOLUS, MOEGISTORHYNCHUS, NEMESTRINIDAE, ORCHIDACEAE, PLATANTHERA, POLLINATION, POLLINATOR SHIFT, POLLINATOR SPECIFICITY, PROBOSCIS, REVIEW, SOUTH AFRICA, SPHINGIDAE, SPIDERS, TABANIDAE, XANTHOPAN}, author = {Staller, E.} }