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Jupiter's auroral emission is a spectacular phenomenon that provides insight into energy release processes related to the coupling of its magnetosphere and ionosphere. This energy release is influenced by solar wind conditions. Using joint observations from Juno and the Hubble Space Telescope (HST), we statistically investigate the relationship between auroral power and current sheet variations under different solar wind conditions. In this study, we reveal that during global main auroral brightening events that are closely connected to solar wind compressions, the dawn side current sheet is substantially thinner than during times when a quiet auroral morphology is present. Furthermore, the total current intensity in the current sheet is found to increase under solar wind compression conditions compared to the quiet period. These findings provide important observational evidence for how magnetospheric dynamics driven by solar wind behavior affect auroral activity, deepening our understanding of the coupling between Jupiter's magnetosphere and ionosphere.

Magnetic Dipolarization, a hallmark indicator of the formation of field‐aligned currents, plays a crucial role in the energy dissipative processes that occur within planetary magnetospheres. Saturn's magnetic dipolarization was found to recur after one planetary rotation, suggesting a potential correlation with the corotating current systems. The observation of enhanced Energetic Neutral Atoms (ENA) within Saturn's inner magnetosphere serves as a diagnostic tool, revealing the existence of a rotating, dynamic Partial Ring Current (PRC) system. By utilizing multiple datasets from Cassini, this study advances the understanding of the interrelationship between ENA emission and magnetic dipolarization. Our results suggest the possibility of a coupling between the PRC system revealed by the ENA emission and magnetic dipolarization. Furthermore, a temporal correlation was found between the ENA emissions and two distinct radio emissions. This study discusses potential causal relationships among these phenomena and first time proposes a global unified physical picture.

We define the spatial clustering of X-rays within Jupiter's northern auroral regions by classifying their distributions into ?X-ray auroral structures.? Using data from Chandra during Juno's main mission observations (24 May 2016 to 8 September 2019), we define five X-ray structures based on their ionospheric location and calculate the distribution of auroral photons. The morphology and ionospheric location of these structures allow us to explore the possibility of numerous X-ray auroral magnetospheric drivers. We compare these distributions to Hubble Space Telescope (HST) and Juno (Waves and MAG) data, and a 1D solar wind propagation model to infer the state of Jupiter's magnetosphere. Our results suggest that the five sub-classes of ?X-ray structures? fall under two broad morphologies: fully polar and low latitude emissions. Visibility modeling of each structure suggests the non-uniformity of the photon distributions across the Chandra intervals are likely associated with the switching on/off of magnetospheric drivers as opposed to geometrical effects. The combination of ultraviolet (UV) and X-ray morphological structures is a powerful tool to elucidate the behavior of both electrons and ions and their link to solar wind/magnetospheric conditions in the absence of an upstream solar monitor. Although much work is still needed to progress the use of X-ray morphology as a diagnostic tool, we set the foundations for future studies to continue this vital research.

An essential factor in assessing the success of woodland restorations is understanding whether gene flow and connectivity between restored and remnant populations has been re-established. Without pollinator services, isolated populations can further subdivide and face concerns of inbreeding depression, which is not the target of restoration projects. Within the ‘Central Valley’ of the Warrumbungle National Park, a series of restoration plantings were performed between the 1980s and 1990s to restore the previously abundant Box-Gum Grassy Woodlands, in particular White Box Gum trees (Eucalyptus albens). Extensive land clearing meant that these populations became extremely fragmented within the agricultural matrix, with only a few remaining extant remnant trees. This restoration was discovered to use locally sourced genetic material for plantations within the park, which is known to cause issues with inbreeding depression and lower genetic variability. Extending upon previous studies, I analysed relictual (historic scattered trees), natural (leftover extant populations), planted (restored trees) and sapling/seedling populations (juveniles grown in situ and ex situ) of E. albens trees for the genetic diversity and population structure by extracting genomic DNA and genotyping of SNP presence and absence conducted using DArTseq microarray developed for Eucalypt species. For the first time for this species, a high-confidence paternity analysis of seedlings and a parent pair analysis of saplings were conducted from a range of populations and were used to quantify pollen-mediated gene flow respectively to analyse connectivity between populations. By combining all analyses, I assessed the genetic success of this mature restoration project, with a focus on determining whether planted populations of E. albens displayed comparable genetic diversity levels and population structure to those of their remnant cohorts and whether there was evidence of gene flow between these groups.

The costs of climate change are often estimated in monetary terms but this raises ethical issues. Here we express them in terms of numbers of people left outside the ‘human climate niche’ – defined as the historically highly-conserved distribution of relative human population density with respect to mean annual temperature (MAT). We show that climate change has already put ~9% of people (>600 million) outside this niche. By end-of-century (2080-2100), current policies leading to around 2.7 °C global warming could leave one third (22-39%) of people outside the niche. Reducing global warming from 2.7 to 1.5 °C results in a ~5-fold decrease in the population exposed to unprecedented heat (MAT ≥29 °C). The lifetime emissions of ~3.5 global average citizens today (or ~1.2 average US citizens) expose 1 future person to unprecedented heat by end-of-century. That person comes from a place where emissions today are around half of the global average. These results highlight the need for more decisive policy action to limit the human costs and inequities of climate change.

Current global challenges call for a rigorously predictive ecology. Our understanding of ecological strategies, imputed through suites of measurable functional traits, comes from decades of work that largely focussed on plants. However, a key question is whether plant ecological strategies resemble those of other organisms. Among animals, ants have long been recognised to possess similarities with plants: as (largely) central place foragers. For example, individual ant workers play similar foraging roles to plant leaves and roots and are similarly expendable. Frameworks that aim to understand plant ecological strategies through key functional traits, such as the ‘leaf economics spectrum’, offer the potential for significant parallels with ant ecological strategies. Here, we explore these parallels across several proposed ecological strategy dimensions, including an ‘economic spectrum’, propagule size-number trade-offs, apparency-defence trade-offs, resource acquisition trade-offs and stress-tolerance trade-offs. We also highlight where ecological strategies may differ between plants and ants. Furthermore, we consider how these strategies play out among the different modules of eusocial organisms, where selective forces act on the worker and reproductive castes, as well as the colony. Finally, we suggest future directions for ecological strategy research, including highlighting the availability of data and traits that may be more difficult to measure, but should receive more attention in future to better understand the ecological strategies of ants. The unique biology of eusocial organisms provides an unrivalled opportunity to bridge the gap in our understanding of ecological strategies in plants and animals and we hope that this perspective will ignite further interest. Read the free Plain Language Summary for this article on the Journal blog.

There may be no such thing as a free meal, but many species have evolved mechanisms for other species to consume the literal fruits of their labors. In the present article, inspired by a chef’s recognition that such species are “nature’s chefs, ” we consider food-making species from the plant, animal, and fungal kingdoms, which produce food or mimic food to increase their own fitness. We identify three ways that species can produce or prepare meals—as food, drinks, or lures—and further distinguish between those providing an honest meal and those deceiving consumers with food mimics. By considering these species holistically, we highlight new hypotheses about the ecology and evolution of the widespread phenomenon of organisms that produce food for other organisms. We find surprising and useful generalities and exceptions among species as different as apple trees and anglerfish by examining species interactions across taxa, systems, and disciplines.