Evolution of pollination niches in a generalist plant clade. Issue 1 (23rd September 2014)

• Record Type: Journal Article
• Authors: Gómez, José María; Perfectti, Francisco; Abdelaziz, Mohamed; Lorite, Juan; Muñoz‐Pajares, Antonio Jesús; Valverde, Javier
• Is Part Of: New phytologist. Volume 205:Issue 1(2015)
• Page Start: 440
• Page End: 453
• Publication Date: 2014-09-23
• Subjects: Erysimum -- modularity -- pollination evolution -- pollination generalization -- pollination niche; Botany -- Periodicals; 580
• DOI: 10.1111/nph.13016
• Languages: English
• ISSNs: 0028-646X

Abstract

Summary: It is widely assumed that floral diversification occurs by adaptive shifts between pollination niches. In contrast to specialized flowers, identifying pollination niches of generalist flowers is a challenge. Consequently, how generalist pollination niches evolve is largely unknown. We apply tools from network theory and comparative methods to investigate the evolution of pollination niches among generalist species belonging to the genus Erysimum . These species have similar flowers. We found that the studied species may be grouped in several multidimensional niches separated not by a shift of pollinators, but instead by quantitative variation in the relative abundance of pollinator functional groups. These pollination niches did not vary in generalization degree; we did not find any evolutionary trend toward specialization within the studied clade. Furthermore, the evolution of pollination niche fitted to a Brownian motion model without phylogenetic signal, and was characterized by frequent events of niche convergences and divergences. We presume that the evolution of Erysimum pollination niches has occurred mostly by recurrent shifts between slightly different generalized pollinator assemblages varying spatially as a mosaic and without any change in specialization degree. Most changes in pollination niches do not prompt floral divergence, a reason why adaptation to pollinators is uncommon in generalist plants.