Aquatic foods to nourish nations.

Despite contributing to healthy diets for billions of people, aquatic foods are often undervalued as a nutritional solution because their diversity is often reduced to the protein and energy value of a single food type ('seafood' or 'fish')1-4. Here we create a cohesive model that unites terrestrial foods with nearly 3,000 taxa of aquatic foods to understand the future impact of aquatic foods on human nutrition. We project two plausible futures to 2030: a baseline scenario with moderate growth in aquatic animal-source food (AASF) production, and a high-production scenario with a 15-million-tonne increased supply of AASFs over the business-as-usual scenario in 2030, driven largely by investment and innovation in aquaculture production. By comparing changes in AASF consumption between the scenarios, we elucidate geographic and demographic vulnerabilities and estimate health impacts from diet-related causes. Globally, we find that a high-production scenario will decrease AASF prices by 26% and increase their consumption, thereby reducing the consumption of red and processed meats that can lead to diet-related non-communicable diseases5,6 while also preventing approximately 166 million cases of inadequate micronutrient intake. This finding provides a broad evidentiary basis for policy makers and development stakeholders to capitalize on the potential of aquatic foods to reduce food and nutrition insecurity and tackle malnutrition in all its forms.

Situating defaunation in an operational framework to advance biodiversity conservation.

Anthropogenic pressures are causing the widespread loss of wildlife species and populations, with adverse consequences for ecosystem functioning. This phenomenon has been widely but inconsistently referred to as defaunation. A cohesive, quantitative framework for defining and evaluating defaunation is necessary for advancing biodiversity conservation. Likening defaunation to deforestation, we propose an operational framework for defaunation that defines it and related terms, situates defaunation relative to intact communities and faunal degradation, and encourages quantitative, ecologically reasonable, and equitable measurements. We distinguish between defaunation, the conversion of an ecosystem from having wild animals to not having wild animals, and faunal degradation, the process of losing animals or species from an animal community. The quantification of context-relevant defaunation boundaries or baselines is necessary to compare faunal communities over space and time. Situating a faunal community on the degradation curve can promote Global Biodiversity Framework targets, advancing the 2050 Vision for Biodiversity.

Drivers and consequences of structure in plant-lemur ecological networks.

Species interactions shape the diversity and resilience of ecological networks. Plant and animal traits, as well as phylogeny, affect interaction likelihood, driving variation in network structure and tolerance to disturbance. We investigated how traits and phylogenetic effects influenced network-wide interaction probabilities and examined the consequences of extinction on the structure and robustness of ecological networks. We combined both mutualistic and antagonistic interactions of animals (55 species, Infraorder Lemuriformes, Order Primates) and their food plants (590 genera) throughout Madagascar to generate ecological networks. We tested the effects of both lemur and plant traits, biogeographic factors and phylogenetic relatedness on interaction probability in these networks using exponential random graph models. Next, we simulated animal and plant extinction to analyse the effects of extinction on network structure (connectance, nestedness and modularity) and robustness for mutualistic, antagonistic and combined plant-animal networks. Both animal and plant traits affected their interaction probabilities. Large, frugivorous lemurs with a short gestation length, occurring in arid habitats, and with a Least Concern threat level had a high interaction probability in the network, given all other variables. Closely related plants were more likely to interact with the same lemur species than distantly related plants, but closely related lemurs were not more likely to interact with the same plant genus. Simulated lemur extinction tended to increase connectance and modularity, but decrease nestedness and robustness, compared to pre-extinction networks. Networks were more tolerant to plant than lemur extinctions. Lemur-plant interactions were highly trait structured and the loss of both lemurs and plants threatened the tolerance of mutualistic, antagonistic and combined networks to future disturbance.

Les interactions des espèces façonnent la diversité et la résilience des réseaux écologiques. Les caractéristiques des plantes et des animaux, ainsi que la phylogénie, affectent la probabilité d'interaction, entraînant des variations dans la structure du réseau et la tolérance aux perturbations. Nous avons étudié comment les traits et les effets phylogénétiques influençaient les probabilités d'interaction à l'échelle du réseau et examiné les conséquences de l'extinction sur la structure et la robustesse des réseaux écologiques. Nous avons combiné les interactions mutualistes et antagonistes des animaux (55 espèces, Infraorder Lemuriformes, Order Primates) et leurs plantes alimentaires (590 genres) à travers Madagascar pour générer des réseaux écologiques. Nous avons testé les effets des caractéristiques des lémuriens et des plantes, des facteurs biogéographiques et de la parenté phylogénétique sur la probabilité d'interaction dans ces réseaux à l'aide de modèles de graphes aléatoires exponentiels. Ensuite, nous avons simulé l'extinction des animaux et des plantes pour analyser les effets de l'extinction sur la structure du réseau (connectance, imbrication et modularité) et la robustesse des réseaux mutualistes, antagonistes et combinés plante-animal. Les caractéristiques animales et végétales ont affecté leurs probabilités d'interaction. Les grands lémuriens frugivores avec une durée de gestation courte, présents dans des habitats arides et avec un niveau de menace Préoccupation mineure avaient une probabilité d'interaction élevée dans le réseau, compte tenu de toutes les autres variables. Les plantes étroitement apparentées étaient plus susceptibles d'interagir avec la même espèce de lémuriens que les plantes éloignées, mais les lémuriens étroitement apparentés n'étaient pas plus susceptibles d'interagir avec le même genre végétal. L'extinction simulée des lémuriens a eu tendance à augmenter la connectivité et la modularité, mais à diminuer l'imbrication et la robustesse, par rapport aux réseaux pré-extinction. Les réseaux étaient plus tolérants aux plantes qu'aux extinctions de lémuriens. Les interactions lémuriens-plantes étaient fortement structurées par des traits et la perte des lémuriens et des plantes menaçait la tolérance des réseaux mutualistes, antagonistes et combinés aux perturbations futures.