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Summary: The diversity of plant–pollinator interactions is grounded in floral resources, with nectar considered one of the main floral rewards plants produce for pollinators. However, a global evaluation of the number of animal‐pollinated nectar‐producing angiosperms and their distribution world‐wide remains elusive.We compiled a thorough database encompassing 7621 plant species from 322 families to estimate the number and proportion of nectar‐producing angiosperms reliant on animal pollination. Through extensive sampling of plant communities, we also explored the interplay between nectar production, floral resource diversity, latitudinal and elevational gradients, contemporary climate, and environmental characteristics.Roughly 223 308 animal‐pollinated angiosperms are nectar‐producing, accounting for 74.4% of biotic‐pollinated species. Global distribution patterns of nectar‐producing plants reveal a distinct trend along latitudinal and altitudinal gradients, with increased proportions of plants producing nectar in high latitudes and altitudes. Conversely, tropical communities in warm and moist climates exhibit greater floral resource diversity and a lower proportion of nectar‐producing plants.These findings suggest that ecological trends driven by climate have fostered the diversification of floral resources in warmer and less seasonal climates, reducing the proportion of solely nectar‐producing plants. Our study provides a baseline for understanding plant–pollinator relationships, plant diversification, and the distribution of plant traits. [ABSTRACT FROM AUTHOR]

Niche partitioning is a common strategy species use to avoid competition for limited resources, allowing them to coexist. Rodent species often reduce competition by spatial segregation and trophic differentiation, but behavioural differences, particularly related to foraging, can also be important. Therefore, temporal segregation can also be an important mechanism for species coexistence, as it helps them avoid sub‐optimal habitats. We found three rodent species (the native Octodon degus and O. lunatus, and the exotic Rattus rattus) foraging on endemic palm Jubaea chilensis seeds, a highly valuable but limited resource. We hypothesized that these rodent species could coexist by segregating foraging in time, showing behavioural differences. To test this, we used camera traps to monitor the fate of J. chilensis seeds and rodent activity at 25 feeding stations. From 596 photographic records, we identified 128 as O. degus, 232 as O. lunatus and 236 as R. rattus. Octodon degus had a diurnal activity, while O. lunatus and R. rattus were nocturnal, showing significant temporal segregation. However, we found no spatial association among these rodents. We found significant behavioural differences in decision and handling times and seed removal rates, with O. degus having the greatest seed removal rate. Nevertheless, we found some nocturnal O. degus records in which the three rodent species were co‐foraging, which may suggest that the resource is limited but valuable enough to shift from exploitation to interference competition. Our results suggest that temporal and behavioural differentiation are more important than spatial segregation and trophic differentiation. Thus, niche partition over multiple dimensions might allow for species coexistence. [ABSTRACT FROM AUTHOR]

Climate change has physiological consequences on organisms, ecosystems and human societies, surpassing the pace of organismal adaptation. Hibernating mammals are particularly vulnerable as winter survival is determined by short-term physiological changes triggered by temperature. In these animals, winter temperatures cannot surpass a certain threshold, above which hibernators arouse from torpor, increasing several fold their energy needs when food is unavailable. Here, we parameterized a numerical model predicting energy consumption in heterothermic species and modelled winter survival at different climate change scenarios. As a model species, we used the arboreal marsupial monito del monte (genus Dromiciops), which is recognized as one of the few South American hibernators. We modelled four climate change scenarios (from optimistic to pessimistic) based on IPCC projections, predicting that northern and coastal populations (Dromiciops bozinovici) will decline because the minimum number of cold days needed to survive the winter will not be attained. These populations are also the most affected by habitat fragmentation and changes in land use. Conversely, Andean and other highland populations, in cooler environments, are predicted to persist and thrive. Given the widespread presence of hibernating mammals around the world, models based on simple physiological parameters, such as this one, are becoming essential for predicting species responses to warming in the short term. [ABSTRACT FROM AUTHOR]

The effects of habitat degradation remain not fully understood. A recent study reported low effects of habitat degradation on plant genetic diversity but indicates that reduction in habitat quality could impact it as well as gene flow indirectly via ecological interactions. Selective logging is a way of habitat degradation, but studies examining its effects on plant genetic diversity on non‐logged forest plant species are relatively scarce. Using 3470 single‐nucleotide polymorphisms, we assess the effects of different selective logging intensities on the genetic diversity of 66 individuals of a keystone mistletoe (Tristerix corymbosus). We also examined the possible relationship with its seed disperser (Dromiciops gliroides) abundance in three sites of the temperate rainforests of southern Chile, with different levels of selective logging intensity. Our results show that selective logging increases allelic richness and inbreeding in this mistletoe; inbreeding increased with selective logging intensity, and heterozygosity decreased with D. gliroides abundance. While wood extraction seems to positively affect T. corymbosus genetic diversity, its long‐term consequences—such as increased inbreeding—are yet to be assessed in future studies. [ABSTRACT FROM AUTHOR]

Mistletoes are parasitic plants that largely rely on animals for pollination and seed dispersal but establish complex interactions with their host plants. Mistletoes are considered keystone species in forest ecosystems as they facilitate several interactions. We studied the fauna associated with two sympatric mistletoe species (Tristerix corymbosus (L.) Kuijt and Desmaria mutabilis (Poepp. & Endl.) Tiegh.) from the temperate rainforests of southern Chile. We set 40 camera traps from November 2021 to May 2022 to monitor the main pollinator (the hummingbird Sephanoides sephaniodes (R. Lesson & Garnot, 1827)), the main seed disperser (the arboreal marsupial Dromiciops bozinovici D'Elía, Hurtado & D'Anatro, 2016), and other animals (birds, mammals, reptiles, and insects). We compared fauna associated with Tristerix corymbosus between spring and summer–fall periods and between Tristerix corymbosus and Desmaria mutabilis during summer–fall. Species composition associated with Tristerix corymbosus showed a significant temporal variation, mainly explained by Sephanoides sephaniodes and Dromiciops bozinovici, which are more abundant in the summer–fall period. We found that animal species composition differences between mistletoe species were mainly explained by S. sephaniodes, Dromiciops bozinovici, and insects. While Tristerix corymbosus was mainly pollinated by hummingbirds, insects frequently visited Desmaria mutabilis flowers. Although both mistletoes have many similarities, they also have some phenology differences that affect their associations with animals, potentially influencing ecological processes. [ABSTRACT FROM AUTHOR]

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Keystone plant species are commonly used for restoring degraded terrestrial sites because, despite being encountered in low abundances in natural communities, they interact with multiple species across multiple niche dimensions. Nevertheless, the demographic characteristics of these "great interactors" are often disregarded in restoration planning, which may bring unintended consequences for restoration trajectories once the outcome of species relationships interplays between positive and negative effects depending on the density of interacting species. Therefore, while replanting keystone species at their characteristically low densities may re‐entangle food webs and allow novel plant and animal recruitment, restoring them at high densities can assemble asymmetrical relationships strong enough to affect sympatric plant species establishment, survival, and reproduction. Here, we explore the negative consequences of overusing keystone plant species in sites undergoing restoration and provide specific guidelines for practitioners to maximize the benefits of keystone plants in restoration initiatives. [ABSTRACT FROM AUTHOR]