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Rapid advances in eradicating invasive species from islands are improving conservation outcomes in these biodiversity hotspots. However, recent conservation gains could be reversed not only by future invasions from non-native species but also by future extinctions of native taxa, both of which may be facilitated by – or exacerbated by interactions among drivers of – global environmental change. We highlight relevant knowledge gaps that must be filled to reduce uncertainty about the ecological effects of future climate change. We use Aotearoa New Zealand as a case study of island ecosystems to demonstrate that in addition to sea-level rise, most ecologically meaningful impacts of climate change on biodiversity responses are indirect and due to exacerbation of existing threats, including the impact of invasive species as well as the loss and fragmentation of habitat. We identify key topics where progress is needed to future-proof conservation management for island ecosystems susceptible to the direct and indirect effects of climate change.

Invasive species can cause shifts in vegetation composition and fire regimes by initiating positive vegetation-fire feedbacks. To understand the mechanisms underpinning these shifts, we need to determine how invasive species interact with other species when burned in combination and thus how they may influence net flammability in the communities they invade. Previous studies using litter and ground fuels suggest that flammability of a species mixture is nonadditive and is driven largely by the more-flammable species. However, this nonadditivity has not been investigated in the context of plant invasions nor for canopy fuels. Using whole shoots, we measured the flammability of indigenous-invasive species pairs for six New Zealand indigenous and four globally invasive plant species, along with single-species control burns. Our integrated measure of flammability was clearly nonadditive, and the more-flammable species per pairing had the stronger influence on flammability in 83 % of combinations. The degree of nonadditivity was significantly positively correlated with the flammability difference between the species in a pairing. The strength of nonadditivity differed among individual flammability components. Ignitability and combustibility were strongly determined by the more-flammable species per pair, yet both species contributed more equally to consumability and sustainability. Our results suggest mechanisms by which invasive species entrain positive vegetation-fire feedbacks that alter ecosystem flammability, enhancing their invasion. Of the species tested, Hakea sericea and Ulex europaeus are those most likely to increase the flammability of New Zealand ecosystems and should be priorities for management.

1. Exotic plant invasions can alter fire regimes in plant communities. Invaders often possess traits that differ from native plants in the community, resulting in increases or declines in community-level flammability, changing fire regimes and potentially causing long-term modifications to plant community composition. Although considering traits of multiple invaders and native species together is useful to better understand how invasions change community-level flammability, few studies have done this. 2. We measured morphological and flammability traits of 51 native and exotic plant species common in tussock grasslands in New Zealand's south-eastern South Island to examine relationships between morphology and whole-plant and shoot-level flammability. Plant community data from 103 permanent transects in this region measured over a 25-year period (c. 1982-2007) were used to determine how flammability changed with increasing levels of plant invasion. 3. Invasion by exotic plants has led to reduced community-level flammability due to shifts from native tussock grasses with high flammability and high fuel loads to mat-forming exotic forbs with low flammability and little fuel. These changes will likely lead to considerable alterations to the fire regime, resulting in lower intensity fires that burn more patchily and for shorter amounts of time, potentially causing further changes in floristic composition. We found considerable differences in flammability across the wide range of species and growth forms that we studied, emphasising the importance of quantifying species-level flammability and the need to avoid treating grasslands as homogenous in terms of their flammability. Total biomass, leaf length and leaf area were the traits most positively correlated with flammability in these tussock grasslands. 4. Synthesis. We show how plant invasions over decadal time-scales have reduced the community-level flammability of tussock grasslands and, for the first time, demonstrate how this can be driven by exotic forbs. The total biomass of constituent species is a useful surrogate for community flammability across a wide range of species and growth forms in both temperate grasslands and savanna ecosystems and should be used in dynamic global vegetation models to assess how flammability varies under various global change scenarios.

A network-based method and computational tool, PIUMet, reveals disease-associated molecular pathways from untargeted metabolomics data without requiring mass-spectral feature identification. Uncovering the molecular context of dysregulated metabolites is crucial to understand pathogenic pathways. However, their system-level analysis has been limited owing to challenges in global metabolite identification. Most metabolite features detected by untargeted metabolomics carried out by liquid-chromatography-mass spectrometry cannot be uniquely identified without additional, time-consuming experiments. We report a network-based approach, prize-collecting Steiner forest algorithm for integrative analysis of untargeted metabolomics (PIUMet), that infers molecular pathways and components via integrative analysis of metabolite features, without requiring their identification. We demonstrated PIUMet by analyzing changes in metabolism of sphingolipids, fatty acids and steroids in a Huntington's disease model. Additionally, PIUMet enabled us to elucidate putative identities of altered metabolite features in diseased cells, and infer experimentally undetected, disease-associated metabolites and dysregulated proteins. Finally, we established PIUMet's ability for integrative analysis of untargeted metabolomics data with proteomics data, demonstrating that this approach elicits disease-associated metabolites and proteins that cannot be inferred by individual analysis of these data.

Flammability is an important plant trait, relevant to plant function, wildfire behaviour and plant evolution. However, systematic comparison of plant flammability across ecosystems has proved difficult because of varying methodologies and assessment of different fuels comprising different plant parts. We compared the flammability of plant species at the leaf‐level (most commonly used in flammability studies) and shoot‐level (which retains aspects of plant architecture). Furthermore, we examined relationships between leaf functional traits and flammability to identify key leaf traits determining shoot‐level flammability. We collated and analysed existing leaf‐ and shoot‐level flammability data from 43 common indigenous perennial New Zealand plant species, along with existing data on leaf morphological and chemical traits. Shoot‐level flammability was decoupled from leaf‐level flammability. Moreover, leaf‐level rankings of flammability were not correlated with rankings of flammability of plants derived from expert opinion based on field observations, while shoot‐level rankings had a significant positive relationship. Shoot‐level flammability was positively correlated with leaf dry matter content (LDMC), phenolics and lignin, and negatively correlated with leaf thickness. Synthesis. Our study suggests that shoot‐level measurements of flammability are a useful and easily replicable way of characterizing the flammability of plants, particularly canopy flammability. With many parts of the world becoming more fire‐prone, due to anthropogenic activities, such as land‐use change and global warming, this finding will help forest and fire managers to make informed decisions about fuel management, and improve modelling of fire‐vegetation‐climate feedbacks under global climate change. Additionally, we identified some key, widely measured leaf traits, such as leaf dry matter content (LDMC), that may be useful surrogates for plant flammability in global dynamic vegetation models. Shoot‐ and leaf‐level flammability were decoupled, and shoot flammability corresponded to rankings based on expert opinion, suggesting that shoot‐level tests are a useful way to characterize the flammability of canopy fuels. Furthermore, we identified some widely measured leaf traits, such as leaf dry matter content, that were highly correlated to shoot flammability and can be useful surrogates for measuring plant flammability.

Despite extensive study of the EGF receptor (EGFR) signaling network, the immediate posttranslational changes that occur in response to growth factor stimulation remain poorly characterized; as a result, the biological mechanisms underlying signaling initiation remain obscured. To address this deficiency, we have used a mass spectrometry-based approach to measure system-wide phosphorylation changes throughout the network with 10-s resolution in the 80 s after stimulation in response to a range of eight growth factor concentrations. Significant changes were observed on proteins far downstream in the network as early as 10 s after stimulation, indicating a system capable of transmitting information quickly. Meanwhile, canonical members of the EGFR signaling network fall into clusters with distinct activation patterns. Src homology 2 domain containing transforming protein (Shc) and phosphoinositol 3-kinase (PI3K) phosphorylation levels increase rapidly, but equilibrate within 20 s, whereas proteins such as Grb2-associated binder-1 (Gab1) and SH2-containing tyrosine phosphatase (SHP2) show slower, sustained increases. Proximity ligation assays reveal that Shc and Gab1 phosphorylation patterns are representative of separate timescales for physical association with the receptor. Inhibition of phosphatases with vanadate reveals site-specific regulatory mechanisms and also uncovers primed activating components in the network, including Src family kinases, whose inhibition affects only a subset of proteins within the network. The results presented highlight the complexity of signaling initiation and provide a window into exploring mechanistic hypotheses about receptor tyrosine kinase (RTK) biology.

Background: Mitigation of wildfires at the wildland–urban interface (WUI) will be enhanced by understanding the flammability of plants growing in this zone. Aims: We aimed to: (1) compare shoot flammability among wildland native, and both urban native and urban exotic ornamental plants; (2) quantify relationships between shoot traits and flammability; and (3) establish flammability scores to distinguish low- from high-flammability species. Methods: Flammability and traits of field-collected shoots were measured and relationships quantified in 44 species from the Blue Mountains World Heritage Area, Australia. Key results: In our study area, urban exotic plants were less flammable than wildland and urban native plants. Slow-igniting shoots had high fuel moisture and bulk density; short-burning shoots had low bulk density and volume; shoots recording low maximum temperatures had high fuel moisture, low bulk density and volume; and shoots with low biomass consumed in flames had high fuel moisture and low volume. Our novel flammability scores distinguished low-flammability (e.g. Lophostemon confertus) from high-flammability native species (e.g. Callistemon citrinus). Conclusions and implications: Low-flammability plantings at the WUI should preferably use native species given potential ecological impacts of exotics. We suggest that future work should seek to identify broader suites of low-flammability native species.

Fire is an important ecological disturbance in vegetated ecosystems across the globe, and also has considerable impacts on human infrastructure. Vegetation flammability is a key bottom-up control on fire regimes, and on the nature of individual fires. Although New Zealand (NZ) historically had low fire frequencies, anthropogenic fires have considerably impacted indigenous vegetation as humans used fire extensively to clear forests. Few studies of vegetation flammability have been undertaken in NZ, and only one has compared the flammability of indigenous plants; this was a qualitative assessment derived from expert opinion. We addressed this knowledge gap by measuring the flammability of terminal shoots from a range of trees and shrubs found in NZ. We quantified shoot flammability of 60 indigenous and exotic species, and compared our experimentally derived ranking with expert opinion. The most flammable species was the invasive exotic shrub Ulex europaeus, followed by Eucalyptus viminalis, Pomaderris kumeraho, Dacrydium cupressinum, and Lophozonia menziesii. Our experimentally derived ranking was strongly correlated with expert opinion, lending support to both methods. Our results are useful to ecologists seeking to understand how fires have and will influence NZ’s ecosystems, and for fire managers identifying high-risk landscapes, and low flammability species for ‘green firebreaks’.

This research examined the intergenerational transmission of depressive symptoms from mothers to their adult children through two succeeding mediators: a child’s perception of emotional availability from their mothers, and a child’s social skills. To do so, this study integrated principles from the integrative model of risk from depressed mother to offspring, attachment theory, and the social skills deficit theory of depression. Child reports of depressive symptoms, perceived emotional availability from mothers, and social skills were assessed as well as mother reports of depressive symptoms from 224 (N = 448) mother-child dyads. Results showed that maternal depressive symptoms were significantly related to child perceptions of emotional availability. Moreover, emotional availability was positively related to child social skills, which in turn was negatively related to child depressive symptoms. Additionally, the indirect effect from maternal depressive symptoms to child depressive symptoms through the mediators was significant. The theoretical and practical implications of these findings are discussed.

• Plant flammability varies across species, but the evolutionary basis for this variation is not well understood. Phylogenetic analysis of interspecific variation in flammability can provide insights into the evolution of plant flammability. • We measured four components of flammability (ignitability, sustainability, combustibility and consumability) to assess the shoot-level flammability of 21 species of Dracophyllum (Ericaceae). Using a macroevolutionary approach, we explored phylogenetic patterns of variation in shoot-level flammability. • Shoot-level flammability varied widely in Dracophyllum. Species in the subgenus Oreothamnus had higher flammability and smaller leaves than those in the subgenus Dracophyllum. Shoot flammability (ignitability, combustibility and consumability) and leaf length showed phylogenetic conservatism across genus Dracophyllum, but exhibited lability among some closely related species, such as D. menziesii and D. fiordense. Shoot flammability of Dracophyllum species was negatively correlated with leaf length and shoot moisture content, but had no relationship with the geographic distribution of Dracophyllum species. • Shoot-level flammability varied widely in the genus Dracophyllum, but showed phylogenetic conservatism. The higher flammability of the subgenus Oreothamnus may be an incidental or emergent property as a result of the evolution of flammability-related traits, such as smaller leaves, which were selected for other functions and incidentally changed flammability.