Seeing through the static: the temporal dimension of plant–animal mutualistic interactions

This is the final version. Available from Wiley via the DOI in this record. Most studies of plant–animal mutualistic networks have come from a temporally static perspective. This approach has revealed general patterns in network structure, but limits our ability to understand the ecological and evolutionary processes that shape these networks and to predict the consequences of natural and human-driven disturbance on species interactions. We review the growing literature on temporal dynamics of plant–animal mutualistic networks including pollination, seed dispersal and ant defence mutualisms. We then discuss potential mechanisms underlying such variation in interactions, ranging from behavioural and physiological processes at the finest temporal scales to ecological and evolutionary processes at the broadest. We find that at the finest temporal scales (days, weeks, months) mutualistic interactions are highly dynamic, with considerable variation in network structure. At intermediate scales (years, decades), networks still exhibit high levels of temporal variation, but such variation appears to influence network properties only weakly. At the broadest temporal scales (many decades, centuries and beyond), continued shifts in interactions appear to reshape network structure, leading to dramatic community changes, including loss of species and function. Our review highlights the importance of considering the temporal dimension for understanding the ecology and evolution of complex webs of mutualistic interactions.National Science FoundationAlexander von Humboldt‐StiftungFP7 People: Marie‐Curie ActionsDeutsche ForschungsgemeinschaftDeutscher Akademischer AustauschdienstFondo para la Investigación Científica y TecnológicaHelmholtz AssociationHelmholtz‐GemeinschaftSeventh Framework Programm

Amazonia Camtrap: a data set of mammal, bird, and reptile species recorded with camera traps in the Amazon forest.

Abstract : The Amazon forest has the highest biodiversity on Earth. However, information on Amazonian vertebrate diversity is still deficient and scatteredacross the published, peer-reviewed, and gray literature and in unpublishedraw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazonregions to compile the most extensive data set of inventories of mammal,bird, and reptile species ever assembled for the area. The complete data setcomprises 154,123 records of 317 species (185 birds, 119 mammals, and13 reptiles) gathered from surveys from the Amazonian portion of eightcountries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru,Suriname, and Venezuela). The most frequently recorded species per taxawere: mammals:Cuniculus paca (11,907 records); birds: Pauxi tuberosa (3713 records); and reptiles:Tupinambis teguixin(716 records). The infor-mation detailed in this data paper opens up opportunities for new ecological studies at different spatial and temporal scales, allowing for a moreaccurate evaluation of the effects of habitat loss, fragmentation, climatechange, and other human-mediated defaunation processes in one of themost important and threatened tropical environments in the world. The data set is not copyright restricted; please cite this data paper when usingits data in publications and we also request that researchers and educator sinform us of how they are using these data

Food-web aggregation, methodological and functional issues

Trophic species in food webs are often aggregated into fewer groups, using theoretical and empirical approaches, either for modelling tractability or because of the lack of data resolution. Heterogeneities in the resolution of food webs used in the literature have led to question their use to establish general topological rules. Despite an increasing number of studies relating topology to ecosystem functioning, we still have no idea on how species' aggregation affects our perception of network functionalities. Therefore, we re-examined the conclusions drawn from an experimental manipulation relating top-predator foraging behaviour and biomass to food-web topology (Lazzaro et al. 2009) by aggregating a 74-species network according to different criteria (taxonomy, trophic similarity, size, expertise). We found that initial significant effects and functional properties were preserved over a large portion of the aggregation gradient (2/3) despite strong variations in the topological descriptor values along the gradient. Aggregation tended to produce more type II errors (false positive) than type I errors, advocating that most effects in aggregated networks are not methodological artefacts. Aggregation by taxonomy, trophic similarity and expertise better preserved functional properties (down to 38, 30 and 17 nodes, respectively) than aggregation by size (down to 40 nodes). Our results suggest that it is possible to relate the structure of aggregated networks to ecosystem properties provided that the methodological approaches are standardized and the level of lumping does not a exceed a reasonable threshold

Predator foraging behaviour drives food-web topological structure

1. The structure and dynamics of prey populations are shaped by the foraging behaviours of their predators. Yet, there is still little documentation on how distinct predator foraging types control biodiversity, food-web architecture and ecosystem functioning. 2. We experimentally compared the effects of model fish species of two major foraging types of lake planktivores: a size-selective visual feeder (bluegill), and a filter feeder (gizzard shad). The visual feeder forages on individually captured consumer prey, whereas the filter feeder forages on various prey simultaneously, not only consumers but also primary producers. We ran a 1-month mesocosm experiment cross-classifying a biomass gradient of each predator type. We analysed the effect of each fish on food-web architecture by computing major topological descriptors over time (connectance, link density, omnivory index, etc.). These descriptors were computed from 80 predator-prey binary matrices, using taxa mostly identified at the species level. 3. We found that the visual feeder induced more trophic cul-de-sac (inedible) primary-producer species, lower link density and connectance, and lower levels of food-web omnivory and generalism than the filter feeder. Yet, predator biomass did not affect food-web topology. 4. Our results highlight that top-predator foraging behaviour is a key functional trait that can drive food-web topology and ultimately ecosystem functioning

Biodiversity enhances the multitrophic control of arthropod herbivory

Arthropod herbivores cause substantial economic costs that drive an increasing need to develop environmentally sustainable approaches to herbivore control. Increasing plant diversity is expected to limit herbivory by altering plant-herbivore and predator-herbivore interactions, but the simultaneous influence of these interactions on herbivore impacts remains unexplored. We compiled 487 arthropod food webs in two long-running grassland biodiversity experiments in Europe and North America to investigate whether and how increasing plant diversity can reduce the impacts of herbivores on plants. We show that plants lose just under half as much energy to arthropod herbivores when in high-diversity mixtures versus monocultures and reveal that plant diversity decreases effects of herbivores on plants by simultaneously benefiting predators and reducing average herbivore food quality. These findings demonstrate that conserving plant diversity is crucial for maintaining interactions in food webs that provide natural control of herbivore pests

sOilFauna: a global synthesis effort on the drivers of soil macrofauna communities and functioning.

Abstract: Understanding global biodiversity change, its drivers, and the ecosystem consequences requires a better appreciation of both the factors that shape soil macrofauna communities and the ecosystem effects of these organisms. The project ?sOilFauna? was funded by the synthesis center sDiv (Germany) to address this major gap by forming a community of soil ecologists, identifying the most pressing research questions and hypotheses, as well as conducting a series of workshops to foster the global synthesis and hypothesis testing of soil macrofauna. The overarching goal is to analyze the most comprehensive soil macrofauna database - the MACROFAUNA database - which collates abundance data of 17 soil invertebrate groups assessed with a standardized method at 7180 sites around the world, and seeks to foster the collection of future data. In a recent kick-off workshop in May 2022, the first research priorities and collaboration guidelines were determined. Here, we summarize the main outcomes of this workshop and highlight the benefits of creating an open global community of soil ecologists providing standardized soil macrofauna data for future research, evaluation of ecosystem health, and nature protection.Workshop report

AMAZONIA CAMTRAP: a dataset of mammal, bird, and reptile species recorded with camera traps in the Amazon forest

The Amazon forest has the highest biodiversity on earth. However, information on Amazonian vertebrate diversity is still deficient and scattered across the published, peer-reviewed and grey literature and in unpublished raw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazon regions to compile the most extensive dataset of inventories of mammal, bird and reptile species ever assembled for the area. The complete dataset comprises 154,123 records of 317 species (185 birds, 119 mammals and 13 reptiles) gathered from surveys from the Amazonian portion of eight countries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru, Suriname and Venezuela). The most frequently recorded species per taxa were: mammals - Cuniculus paca (11,907 records); birds - Pauxi tuberosa (3,713 records); and reptiles - Tupinambis teguixin (716 records). The information detailed in this data paper opens-up opportunities for new ecological studies at different spatial and temporal scales, allowing for a more accurate evaluation of the effects of habitat loss, fragmentation, climate change and other human-mediated defaunation processes in one of the most important and threatened tropical environments in the world. The dataset is not copyright restricted; please cite this data-paper when using its data in publications and we also request that researchers and educators inform us of how they are using this data