The long and the short of it: a global analysis of hawkmoth pollination niches and interaction networks

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. 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. 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 long-proboscid hawkmoths. 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.Fil: Johnson, Steven D.. University of KwaZulu Natal; SudáfricaFil: More, Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Amorim, Felipe W.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Haber, William A.. Monteverde; Costa RicaFil: Frankie, Gordon W.. University of California Berkeley; Estados UnidosFil: Stanley, Dara A.. University of KwaZulu Natal; SudáfricaFil: Cocucci, Andrea Aristides. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Raguso, Robert A.. Cornell University; Estados Unido

Domestication of the Triticeae in the Fertile Crescent

WOS: 000268721700003About 12,000 years ago, humans began the transition from hunter-gathering to a sedentary, agriculture-based society. From its origins ill the Fertile Crescent, farming expanded throughout Europe, Asia and Africa, together with various domesticated plants and animals. Where, how and why agriculture originated is still debated. Progress has been made in Understanding plant domestication in the last few years. New insights were obtained mainly due to (I) the use of comprehensive germplasm collections covering the whole distribution area for each species; (II) the comparison of many wild and domesticated accessions for each species; (III) the identification of the wild progenitor in the wild gene pool and its comparison with domesticate descendants (IV) the use of molecular fingerprinting techniques at many loci and the access to new generation high-throughput sequencing technologies; (V) the identification and cloning of genes involved in domestication, and (VI) excavation campaigns. This chapter reviews the recent knowledge on wheat, barley and rye domestication in the Fertile Crescent and covers several issues concerning the molecular knowledge of the effects induced by domestication and breeding of these crops