DOI: 10.5061/dryad.qfttdz0hr
title: Integrating nocturnal and diurnal interactions in a Neotropical pollination network

description: Plants establish pollination interactions with different groups of
 animals, including nocturnal ones that establish interactions with
 economically valuable and culturally important crops, as well as wild
 plants of conservation concern. Despite the considerable number of studies
 addressing the structure and dynamic of pollination networks, nocturnal
 interactions have been relatively overlooked. Using a multilayer network
 approach and considering diurnal and nocturnal interactions, we aimed to
 understand how interactions at different periods of the day are integrated
 and contribute to the network structural pattern. We also aimed to
 highlight how multilayer networks may give a more nuanced assessment of
 species importance across layers. We assembled a pollination network of an
 intensively studied Neotropical area by standardizing interaction data
 from 16 previous studies into a presence/absence (binary) network. Then we
 used a multilayer network approach to evaluate the network modularity and
 plant species' roles in these different temporal layers. Plants were
 classified as nocturnal or diurnal according to the onset of floral
 opening and pollinators were classified according to their foraging
 period. The network consisted of 178 pollinator species and 158 plant
 species, with 870 links. Among plant species, 135 species have diurnal
 floral opening while 23 species are nocturnal. The multilayer network was
 significantly modular, and these modules differed in the composition of
 pollinator groups (e.g., hawk moths, bats, bees, hummingbirds), as well as
 of diurnal and nocturnal plants. We show that diurnal and nocturnal
 interactions are organized into interconnected modules in the multilayer
 network. Nocturnal plants had higher values of versatility and multidegree
 than diurnal plants, due to their role in connecting the two temporal
 layers. Synthesis. Our study highlights the importance of integrating
 different pollination systems to understand the importance of distinct
 components that structure pollination networks. We also illustrate the
 value of tapping into existing information, particularly species
 interaction data, from well studied biodiversity hotspot areas, to gain a
 better understanding of how communities are structured. Finally, despite
 the relative scarcity of nocturnal pollination network studies, we showed
 nocturnal plants, which often make complementary use of diurnal
 pollinators, to be important in connecting the temporal layers.
description: The plant-pollinator interactions analysed here were sampled at
 the Panga Ecological Station (PES), located around 40 km from the centre
 of Uberlândia city, state of Minas Gerais, Brazil (19.156° – 19.186° S and
 48.389° – 48.410° W, altitude ≈ 800 m above sea level). The PES is a 405ha
 Private Reserve of Natural Heritage (IBAMA Ordinance
 N<sup>o</sup>. 072/97 of June 4, 1997) that was created in
 1986 by the Federal University of Uberlândia to carry out research in
 preserved Cerrado environments. It contains several types of vegetation
 typical of the Cerrado, a large Neotropical savanna ecosystem, including
 savanna, forest, and open grassland areas. Climate in the region shows two
 well defined seasons: one cooler and drier, between May and September; and
 a warmer and wetter period, from October to April. We
 compiled all the known studies on plant-pollinator interactions conducted
 in the PES, carried out between 1990 and 2017, each focusing on distinct
 groups of plants and pollinators, using different sampling approaches most
 appropriate for each group, including focal observation or pollinators
 capture for pollen load identification. The information on
 plant-pollinator interactions were organized into a binary matrix, with
 pollinators in the columns and plants in the rows. Each cell was filled
 with 1 when an interaction between the pair of a plant and pollinator was
 recorded and 0 otherwise.