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Fire-prone landscapes experience frequent fires, disrupting above-ground biomass and altering below-ground soil nutrient availability. Augmentation of leaf nutrients or leaf water balance can both reduce limitations to photosynthesis and facilitate post-fire recovery in plants. These modes of fire responses are often studied separately and hence are rarely compared. We hypothesized that under severe burning, woody plants of a coastal scrub ecosystem would have higher rates of photosynthesis (A net) than in unburned areas due to a transient release from leaf nutrient and water limitations, facilitating biomass recovery post-burn. To compare these fire recovery mechanisms in regrowing plants, we measured leaf gas exchange, leaf and soil N and P concentrations, and plant stomatal limitations in Australian native coastal scrub species across a burn sequence of sites at 1 year after severe fire, 7 years following a light controlled fire, and decades after any fire at North Head, Sydney, Australia. Recent burning stimulated increases in A net by 20% over unburned trees and across three tree species. These species showed increases in total leaf N and P as a result of burning of 28% and 50% for these macronutrients, respectively, across the three species. The boost in leaf nutrients and stimulated leaf biochemical capacity for photosynthesis, alongside species-specific stomatal conductance (g s) increases, together contributed to increased photosynthetic rates after burning compared with the long-unburned area. Photosynthetic stimulation after burning occurred due to increases in nutrient concentrations in leaves, particularly N, as well as stomatal opening for some species. The findings suggest that changes in species photosynthesis and growth with increased future fire intensity or frequency may be facilitated by changes in leaf physiology after burning. On this basis, species dominance during regrowth depends on nutrient and water availability during post-fire recovery. [ABSTRACT FROM AUTHOR]

Context: Phytophthora cinnamomi has been present in Two Peoples Bay Nature Reserve in Western Australia for decades, with impacts observed in susceptible plant communities. Aims: This study aimed to examine the past and present impact of P. cinnamomi on ecosystems. Methods: The distribution of P. cinnamomi was mapped 1983–1995 and reassessed in 2024. The long-term spread of the pathogen was measured. Plant densities were assessed, dry-weight biomass measured, and visits by avifauna quantified in infested and healthy vegetation. The persistence of chlamydospores was assessed. Key results: Mapping confirmed the widespread distribution of P. cinnamomi in the Reserve, with some areas mapped as disease-free up to 1995 now infested. Phytophthora dieback has spread in Banksia shrubland at an average of 1.5 m/year over a 33-year period. The density of species from the Proteaceae, Fabaceae, Ericaceae, and Hibbertia was significantly reduced; and the biomass of non-sedge species and visits by avifauna lower in infested compared with healthy Banksia shrubland. However, pockets of healthy habitat persist in infested areas and two highly susceptible Ericaceae (Leucopogon glabellus , Styphelia flavescens) were observed in high numbers in infested vegetation. Recovery of chlamydospores confirmed the persistence of the pathogen behind the dieback front. Conclusions: The impact of P. cinnamomi is long term and irreversible, however, some susceptible species may have mechanisms to ensure their persistence through prolific seed production. Implications: Protection of areas of healthy susceptible habitat from the introduction and spread of P. cinnamomi , the implementation of existing control measures and research into alternative measures continue to be a priority. Plant disease caused by the root pathogen Phytophthora cinnamomi has resulted in significant changes to susceptible plant communities in Two Peoples Bay Nature Reserve. The long history of the pathogen in the Reserve, with studies on disease distribution and impact dating from the 1980s, provides an opportunity to examine the past and present impact of P. cinnamomi on ecosystems. This article belongs to the Collection The Natural History of Two Peoples Bay Nature Reserve, Western Australia. [ABSTRACT FROM AUTHOR]

Context: Phytophthora cinnamomi Rands is a destructive pathogen of Australian native vegetation, often causing permanent damage to ecosystems and threatening the survival of rare, susceptible species. Despite that, much information about the effects of P. cinnamomi on plant species remains unpublished and the risk of extinction to most species is unknown. Aims: We aimed to classify the risk of extinction from P. cinnamomi to Australian native plants. Methods: We used available data and personal knowledge about P. cinnamomi effects on plants, spatial data on plant species distribution and habitat suitability of P. cinnamomi to assign an extinction-risk category of low, moderate, high or very high. Key results: There are currently 65 plant species at a very high risk of extinction in Australia as a result of P. cinnamomi infection. The genera Andersonia , Banksia , Darwinia , Daviesia , Epacris , Gastrolobium , Grevillea , Hibbertia , Isopogon , Lambertia , Latrobea , Leucopogon , Phebalium and Styphelia have multiple species at a very high risk of extinction, most of which occur in south-western Western Australia. Conclusions: The available data confirmed the high risk to the Australian flora from P. cinnamomi and identified species in plant families not previously known to be affected, highlighting data gaps (e.g. lack of knowledge about effects and risk in orchids and grasses). Implications: Much more work is required to fully understand the risk from P. cinnamomi (and other Phytophthora species) to the Australian flora. The magnitude of the extinction risk to Australia's flora from Phytophthora cinnamomi is poorly known. Using available data, we found that the genera Andersonia , Banksia, Darwinia, Daviesia, Epacris, Gastrolobium, Grevillea, Hibbertia, Isopogon, Lambertia, Latrobea, Leucopogon, Phebalium and Styphelia have multiple species at a very high risk of extinction because of this pathogen. As many as 269 plant species may be at a very high risk of extinction on the basis of phylogenetic patterns. Photographs by Keith McDougall. [ABSTRACT FROM AUTHOR]

Honeys produced by Apis mellifera from different flowering plants can vary widely in their characteristics. Some floral sources yield honeys with especially high antibacterial and/or antioxidant activity, which may be candidates for further evaluation as therapeutic agents. This study investigated 115 honeys harvested from three Western Australian coastal bioregions: the Swan coastal plain, Geraldton sandplains and Dampierland. Honeys were derived from a range of floral sources, including Agonis, Banksia, Calothamnus, Callistemon, Eucalyptus, Leptospermum and Melaleuca, and several multifloral honeys including wildflower honey were also included. HPTLC fingerprinting was used to analyse the phenolics fractions of all honeys and fingerprints were analysed to attempt to verify the floral source of each honey. Typical fingerprints were discernible for the four honeys derived from Agonis flexuosa, Banksia sessilis, Banksia menziesii and Calothamnus. Antibacterial and anti-oxidant activity was quantified for all honeys and showed that Calothamnus honeys had the highest activity for both, and also contained the highest levels of phenolics. Hydrogen peroxide, colour and water content were also determined. Data obtained for all 115 honeys were analysed by principal component analysis to investigate broad trends, and showed that colour, total phenolics and antioxidant activity correlated strongly, whereas antibacterial activity was not strongly correlated with any other factors. Data obtained for individual floral sources were analysed by one-way analysis of variance and revealed significant differences between some honey types, supporting the hypothesis that honeys derived from different floral sources vary in important characteristics such as antibacterial and antioxidant activity. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to evaluate the effects of storage and different temperatures on the antibacterial activity and physicochemical characteristics of several types of honey. Methods and results: Honeys stored for 16 weeks at 37 and 45◦C showed significant declines in antibacterial activity determined by minimum inhibitory concentrations, the loss of hydrogen peroxide, decreases in honey pH, and increases in honey colour, with changes most pronounced at 45◦C. In contrast, honeys stored for 16 weeks at ambient (∼22◦C) and cold (4, −20, and −80◦C) temperatures showed only minor changes. In a second set of 12 honeys stored for 16–32 months at ambient temperature and then 4◦C, honeys showed minor changes in antibacterial activity, increases in colour, and decreases in pH. For a third set of 17 honeys stored for five years at ambient temperature, the honeys showed almost complete loss of hydrogen peroxide and were all significantly darker in colour, but showed varied changes in antibacterial activity. Conclusions: Heat was detrimental to the antibacterial activity of honeys, as was long-term storage at ambient temperatures for some honeys but not others. [ABSTRACT FROM AUTHOR]

The frequency and intensity of drought events are predicted to increase because of climate change, threatening biodiversity and terrestrial ecosystems in many parts of the world. Drought has already led to declines in functionally important tree species, which are documented in dieback events, shifts in species distributions, local extinctions, and compromised ecosystem function. Understanding whether tree species possess the capacity to adapt to future drought conditions is a major conservation challenge. In this study, we assess the capacity of a functionally important plant species from south-eastern Australia (Banksia marginata, Proteaceae) to adapt to water-limited environments. A water-manipulated common garden experiment was used to test for phenotypic plasticity and genetic adaptation in seedlings sourced from seven provenances of contrasting climate-origins (wet and dry). We found evidence of local adaptation relating to plant growth investment strategies with populations from drier climate-origins showing greater growth in well-watered conditions. The results also revealed that environment drives variation in physiological (stomatal conductance, predawn and midday water potential) and structural traits (wood density, leaf dry matter content). Finally, these results indicate that traits are coordinated to optimize conservation of water under water-limited conditions and that trait coordination (phenotypic integration) does not constrain phenotypic plasticity. Overall, this study provides evidence for adaptive capacity relating to drought conditions in B. marginata, and a basis for predicting the response to climate change in this functionally important plant species. [ABSTRACT FROM AUTHOR]

The frequency and intensity of drought events are predicted to increase because of climate change, threatening biodiversity and terrestrial ecosystems in many parts of the world. Drought has already led to declines in functionally important tree species, which are documented in dieback events, shifts in species distributions, local extinctions, and compromised ecosystem function. Understanding whether tree species possess the capacity to adapt to future drought conditions is a major conservation challenge. In this study, we assess the capacity of a functionally important plant species from south-eastern Australia (Banksia marginata, Proteaceae) to adapt to water-limited environments. A water-manipulated common garden experiment was used to test for phenotypic plasticity and genetic adaptation in seedlings sourced from seven provenances of contrasting climate-origins (wet and dry). We found evidence of local adaptation relating to plant growth investment strategies with populations from drier climate-origins showing greater growth in well-watered conditions. The results also revealed that environment drives variation in physiological (stomatal conductance, predawn and midday water potential) and structural traits (wood density, leaf dry matter content). Finally, these results indicate that traits are coordinated to optimize conservation of water under water-limited conditions and that trait coordination (phenotypic integration) does not constrain phenotypic plasticity. Overall, this study provides evidence for adaptive capacity relating to drought conditions in B. marginata, and a basis for predicting the response to climate change in this functionally important plant species.

Context: As threatening processes continue to impact rare plant populations, the use of translocations is becoming increasingly frequent. The ultimate success of translocation, attaining long-term persistence, is determined by species' ability to reproduce, recruit, and maintain levels of genetic diversity that permits the capacity to adapt to environmental change. Aims: This study aimed to assess translocation success of Banksia brownii. Methods: We compared genetic diversity, reproductive output and aspects of the mating system of a translocated population with four reference wild populations. Key results: We found that the use of multiple source populations for the translocation resulted in levels of genetic diversity comparable to reference populations of high diversity. Reproductive output was highest in the translocated population and a positive relationship between plant size and number of flowers across all populations was evident. However, mating system analysis revealed a large difference in outcrossing rates between populations in different habitats despite common pollinators, with the translocated population having the highest rates of selfing. Conclusion: Whilst genetic diversity and reproductive output were comparable or higher in the translocated population than in the reference populations, assessing translocation outcomes by these measures alone can potentially mask the longer-term erosion of genetic diversity through unfavourable patterns of mating. Implications: We recommend using multiple metrics of reproductive, recruitment and genetic diversity to properly assess plant translocation success. Genetic diversity and the processes that maintain it are key considerations for translocation success. Here we compare genetic diversity, mating systems, pollination and reproductive output of a translocated population of Banksia brownii with wild populations. Genetic diversity and reproductive output were comparable or higher in the translocated population than in the reference populations indicating success, however the translocated population had the highest levels of selfing. As such we recommend incorporating both genetic monitoring and demographic assessment when evaluating translocation outcomes. Image: Rebecca Dillon. Photo credit: Rebecca Dillon. [ABSTRACT FROM AUTHOR]

Seed fungal endophytes play an important beneficial role in the formation of the seedling mycobiome and contribute to plant establishment, but can also occur as latent pathogens and saprotrophs. Current knowledge on the function and diversity of seed fungal endophytes has been gained through studies in agricultural systems whilst knowledge from natural systems is relatively less. We used two co-occurring species from the genus Banksia from four sites in Australia's Sydney Basin Bioregion to investigate the abundance and diversity of seed fungal endophyte communities present in natural ecosystem hosts. Based on results from culturing and DNA sequence analysis of multiple loci, we found that Banksia seeds house a diverse range of fungal endophyte species, that when assigned to functional guilds belonged to multiple trophic modes. Thirty-one of the fungal taxa identified had not been previously reported as endophytes. Amongst the 58 Operational Taxonomic Units identified, Leotiomycetes and Sordariomycetes were the dominant classes and Banksiamyces (Leotiomycetes) and Penicillium (Sordariomycetes) the dominant genera, with many of the species isolated recorded in the literature as having a limited distribution. The two Banksias shared few fungal endophyte species, which were not always present across all study sites. We revealed a 'hidden diversity' within seeds of Banksia from natural ecosystems and provided insights into the influence host species can have on the seed mycobiome. • Fifty-eight fungal taxa were isolated from Banksia ericifolia and B. serrata seed. • Thirty-one of the 58 seed fungi had not been recorded as seed endophytes previously. • Majority of isolated fungi were Banksiamyces and Penicillium. • Majority of seed fungi isolated were assigned as saprotrophs or multi-trophic ecologicalmodes. • The two Banksia species shared few fungal species, which were not always present across all study sites. [ABSTRACT FROM AUTHOR]

Premise: Understanding evolutionary history and classifying discrete units of organisms remain overwhelming tasks, and lags in this workload concomitantly impede an accurate documentation of biodiversity and conservation management. Rapid advances and improved accessibility of sensitive high‐throughput sequencing tools are fortunately quickening the resolution of morphological complexes and thereby improving the estimation of species diversity. The recently described and critically endangered Banksia vincentia is morphologically similar to the hairpin banksia complex (B. spinulosa s.l.), a group of eastern Australian flowering shrubs whose continuum of morphological diversity has been responsible for taxonomic controversy and possibly questionable conservation initiatives. Methods: To assist conservation while testing the current taxonomy of this group, we used high‐throughput sequencing to infer a population‐scale evolutionary scenario for a sample set that is comprehensive in its representation of morphological diversity and a 2500‐km distribution. Results: Banksia spinulosa s.l. represents two clades, each with an internal genetic structure shaped through historical separation by biogeographic barriers. This structure conflicts with the existing taxonomy for the group. Corroboration between phylogeny and population statistics aligns with the hypothesis that B. collina, B. neoanglica, and B. vincentia should not be classified as species. Conclusions: The pattern here supports how morphological diversity can be indicative of a locally expressed suite of traits rather than relationship. Oversplitting in the hairpin banksias is atypical since genomic analyses often reveal that species diversity is underestimated. However, we show that erring on overestimation can yield negative consequences, such as the disproportionate prioritization of a geographically anomalous population. [ABSTRACT FROM AUTHOR]

Serotinous plants that both release seed and resprout after fire are thought to be resistant to wildfires within the range of intensities that have been experienced up until now. However, the frequency and scale of intense wildfires is increasing under climate change. We studied annual flowering and fruit‐set in a large population of Banksia spinulosa plants in south‐eastern Australia from the early 1990s to 2006. The results led us to predict that there would be little recruitment from seedlings after the next fire but good resprouting from very long‐lived lignotubers. Our study population burned in the widespread, high‐intensity wildfires of December 2019, providing an opportunity to test the hypothesis. Most above‐ground stems and cones were reduced to ash, and only 15 cones (on 10 plants) remained after the fire. We found no seedlings in the 0.3 ha site that had initially contained over 350 adult plants. Little natural mortality had been observed pre‐fire, but by 5 months after the fire, nearly 25% of lignotubers had failed to resprout. We conclude that even common and widespread resprouting species will suffer population decline and reduced genetic diversity as high‐intensity fires become more extensive and frequent. [ABSTRACT FROM AUTHOR]

Context and aim: Stands of the critically endangered Banksia conferta in north-eastern New South Wales show low recruitment and were examined to elucidate whether pollinator absence or fire history best explained this. Methods: Motion-detection cameras were deployed at three sites to identify potential pollinators, and age structure within stands and past follicle production were assessed through tree measurements and follicle counts. Key results: In total, 691 fauna-triggered image sequences were recorded between June and December 2019. Six mammal and 10 bird species were detected, but only 10 of these were observed probing inflorescences. White-cheeked Honeyeater and Sugar Glider combined comprised 66% of all fauna interactions, and of all 400 Banksia probes, 45% were from White-cheeked Honeyeaters and 18% were by Sugar Gliders. Different size structures of B. conferta were evident at each site, consistent with older and younger populations post-fire. Significantly more Banksia individuals (5×) were present at the younger site, likely governing pollinator composition through interspecific competition within pollinator guilds, and past follicle production was also greater here. Conclusions: Pollinator absence is not the cause of low recruitment in this population, and current stand structure and follicle production reflect past fire history. The three sites differed in their dominant fauna foragers, suggesting that B. conferta is a pollinator-generalist. Birds appear to operate as the key pollinating species during the day but are replaced by small mammals at night. Follicle production is higher in younger post-fire plants. Implications: The absence of fire from older populations for over 55 years is of concern, and population decline seems likely without fire intervention. The critically endangered Banksia conferta, known in New South Wales from a single aging population in former production forests, has shown low seed production over recent years and is declining. Much of its habitat has remained unburnt for over 50 years, and it is unclear whether fire absence or low pollinator populations are driving this decline. Motion-detection cameras identified considerable pollinator activity, and when coupled with analysis of Banksia demography data, imply that fire is needed to replenish populations. [ABSTRACT FROM AUTHOR]

On‐plant storage of seeds (serotiny) is a feature of many fire‐prone dominant trees and shrubs in North America, Mediterranean Basin, South Africa and Australia. Understanding how it has responded to the prevailing fire regime and recruitment/growing conditions, and its genetic basis and adaptive significance, depends on the use of an accurate index of the level of serotiny.Seven indices, three measuring 'apparent' serotiny and four measuring 'inherent' serotiny, were evaluated for their ability to reflect the extent to which seeds are stored in the crown for later release. The most widely used indices ignore the temporal aspects of seed attrition and are vulnerable to plant size, age, fecundity and local growing‐condition effects, while age of the oldest crop year with closed cones/fruits depends on the accuracy of a single observation. Presence/absence of serotiny at the individual tree level ignores the effect of plant age on the expression of serotiny.The slope of the line through the percentage of cones/fruits that still retain their seeds in progressively older crop years, the 'degree of serotiny' (100/slope), is shown to be unbiased by annual fluctuations in crop size, differences in plant age or variations in local growing conditions. It also corresponds to a probability, and thus more accurate, estimate of age of the oldest unopened structures. Since seeds have a lower % viability than the % of supporting cones/fruits closed at any age, there is a case for applying the slope method to the fraction of viable seeds retained to arrive at an estimate of the age of the oldest viable seeds on the plant, as the ultimate index of serotiny.If the level of serotiny is to be related to the fire regime, then care needs to be taken to use records over a sufficiently long time to have had an evolutionary impact, unless this is being used against controls to examine a genetic response to the new fire regime.Synthesis. Among seven currently available indices of serotiny, the slope measure is shown to be the most accurate for studies that relate the level of serotiny to the fire regime and habitat conditions under which the species evolved, as well as for examining its heritability. Attention needs to shift from just recording cones/fruits closed to include the viability of seeds that remain as a better basis for understanding the role of serotiny in post‐fire recruitment. [ABSTRACT FROM AUTHOR]

Pollen dispersal is the step in higher plant mating systems over which the parent plant has the least control as it is dependent on the vagaries of weather conditions (anemophily) or animal behaviour (animal pollinator activity). While many families have passive release from the anther the Proteaceae has a diversity of pollen dispersal methods. Flowers from a range of species in the Proteaceae, covering the majority of genera from each of the four main subfamilies, were examined to determine how pollen is dispersed and to gain an overall view of how male function varies within the family. This provides a basis for predicting the degree of the six likely fates of pollen released in this family. Only one group (subfamily Persoonioideae) and four genera in one other subfamily (Proteoideae) dispense pollen directly from the anthers onto a flower visitor. Five genera in the Proteoideae have explosive pollen release, while Symphionema may require vibration to release the pollen. All the remaining Proteoideae genera, the single species of Bellendenoideae, and all genera of the Grevilleoideae (except Sphalmium) have a pollen presenter where pollen is dispersed from the style of the flower. Ancestral Proteaceae were likely to have been insect pollinated and had relatively small flowers. Taxa with explosive pollen release may have evolved early in the family and may have been more abundant early in the fossil record. However, the taxa with pollen presenters became much more abundant throughout the Tertiary when many developed robust gynoecia that can accommodate larger vertebrate pollinators. [ABSTRACT FROM AUTHOR]

Various factors influence patterns of genetic diversity within and between populations that are important considerations for plant conservation. Both clonality and population genetic differentiation are key factors informing conservation actions, especially for rare species. Banksia mimica is a rare species that occurs in three disjunct locations in the biodiversity hotspot of the southwest Australian Floristic Region of Western Australia. Extant populations are suspected to have varying levels of clonality and high levels of genetic differentiation due to geographic disjunction. A genetic analysis was undertaken in order to confirm clonal reproduction and obtain initial estimates of genotypic diversity, and to assess genetic diversity within, and genetic structure among, populations. Genotypic richness ranged from 0.210 to 1.00 supporting observations in the field of variable degrees of clonal growth. The most clonal populations showed genetic signals of greater levels of observed heterozygosity than expected heterozygosity and negative FIS values that were not present in other populations of B. mimica or populations of the nonclonal sister taxon B. vestita. There was strong genetic structure with high genetic divergence among geographically disjunct population groups (global FST = 0.392, DST = 0.475), as is often found within the Australian flora. Genetic differentiation among disjunct populations located on the Whicher Scarp and more northern populations approached, or was greater than, that between Whicher populations and populations of the sister taxa B. vestita. This result is consistent with several other species that show genetic differentiation in disjunct populations located on the Whicher Scarp geomorphological formation. Results suggest a reassessment of the taxonomy and identification of evolutionary significant units for populations of B. mimica would support effective conservation management of this species. [ABSTRACT FROM AUTHOR]

Serotiny is the prolonged storage of seeds in closed cones or fruits held within the crown of woody plants. It is widespread throughout fireprone vegetation with a predominantly winter rainfall, especially in Mediterrnanean-type ecosystems (MTEs). Nonstorage is a feature of fireprone vegetation with summer-dominant rainfall or nonfireprone vegetation. Serotiny confers fitness benefits on an individual when fire return intervals fall between age to reproductive maturity and the plant life span. The level of serotiny within and between species varies greatly along a continuum indicating highly plastic responses to different environmental conditions. Here we review how and why the traits that underpin this reproductive syndrome evolved and continue to control the occurrence of species in contemporary landscapes. We documented 1345 serotinous species in fireprone regions of Australia, South Africa, the Mediterranean Basin, North America, and Asia. The length of seed storage varies from a few years (weak serotiny) to >10 years (strong serotiny), with remarkable diversity even within clades. We show how the interplay between postfire and interfire seedling recruitment dictates the expression of serotiny along a strong serotiny/nonserotiny continuum, and that, where strong serotiny is favored, the 'gene support for serotiny' builds up over successive generations. Nonserotiny is favored in the absence of fire or occurs at intervals exceeding plant longevity, but also when the fire is so frequent that only resprouters can survive. We identify 23 traits associated with serotiny/nonserotiny syndromes that are subject to both environmental and phylogenetic constraints. While all are coordinated for maximum fitness, some traits, such as protection from granivores, are only indirectly related to the fire regime. Serotiny has a long history extending back to the Triassic. The rate of serotinous-lineage proliferation has fluctuated greatly over time but peaked over the last 5 million years. Nonserotinous species have evolved from serotinous ancestors in response to increased fire frequency, or as plants migrated to fire-free habitats. We note that contemporary shifts in climate, land-use, and exploitation have had a profound, but disproportionate, effect on the conservation status and evolutionary trajectory of serotinous species in MTEs. Escalating anthropogenic impacts increase the need to understand how and why serotiny is such a prominent feature of some fireprone ecosystems. We highlight avenues for future research and argue for the use of temporally based measures of serotiny to facilitate comparisons between studies. [ABSTRACT FROM AUTHOR]

Wildfires are a natural component in many terrestrial ecosystems and often play a crucial role in maintaining biodiversity, particularly in the fire-prone regions of Australia. A prime example of plants that are able to persist in these regions is the genus Banksia. Most Banksia species that occur in fire-prone regions produce woody seed pods (follicles), which open during or soon after fire to release seeds into the post-fire environment. For population persistence, many Banksia species depend on recruitment from these canopy-stored seeds. Therefore, it is critical that their seeds are protected from heat and rapid oxidation during fire. Here, we show how different species of Banksia protect their seeds inside follicles while simultaneously opening up when experiencing fire. The ability of the follicles to protect seeds from heat is demonstrated by intense 180 s experimental burns, in which the maximum temperatures near the seeds ranged from ∼75°C for B. serrata to ∼90°C for B. prionotes and ∼95°C for B. candolleana, contrasting with the mean surface temperature of ∼450°C. Many seeds of native Australian plants, including those of Banksia, are able to survive these temperatures. Structural analysis of individual follicles from these three Banksia species demonstrates that all of them rely on a multicomponent system, consisting of two valves, a porous separator and a thin layer of air surrounding the seeds. The particular geometric arrangement of these components determines the rate of heat transfer more than the tissue properties alone, revealing that a strong embedment into the central rachis can compensate for thin follicle valves. Furthermore, we highlight the role of the separator as an important thermal insulator. Our study suggests that the genus Banksia employs a variety of combinations in terms of follicle size, valve thickness, composition and geometric arrangement to effectively protect canopy-stored seeds during fire.

Summary: Many Proteaceae are highly phosphorus (P)‐sensitive and occur exclusively on old nutrient‐impoverished acidic soils (calcifuge), whilst a few also occur on young calcareous soils (soil‐indifferent) that are higher in available calcium (Ca) and P. Calcium increases the severity of P‐toxicity symptoms, but its underlying mechanisms are unknown. We propose that Ca‐enhanced P toxicity explains the calcifuge habit of most Proteaceae.Four calcifuge and four soil‐indifferent Proteaceae from South‐Western Australia were grown in hydroponics, at a range of P and Ca concentrations.Calcium increased the severity of P‐toxicity symptoms in all species. Calcifuge Proteaceae were more sensitive to Ca‐enhanced P toxicity than soil‐indifferent ones. Calcifuges shared these traits: low leaf zinc concentration ([Zn]), low Zn allocation to leaves, low leaf [Zn]:[P], low root : shoot ratio, and high seed P content, compared with soil‐indifferent species.This is the first demonstration of Ca‐enhanced P toxicity across multiple species. Calcium‐enhanced P toxicity provides an explanation for the calcifuge habit of most Proteaceae and is critical for the management of this iconic Australian family. This study represents a major advance towards an understanding of the physiological mechanisms of P toxicity and its role in the distribution of Proteaceae. [ABSTRACT FROM AUTHOR]

Landscape degradation is a major threat to global biodiversity that is being further exacerbated by climate change. Halting or reversing biodiversity decline using seed-based restoration requires tons of seed, most of which is sourced from wild populations. However, in regions where restoration is most urgent, wild seed sources are often fragmented, declining and producing seed with low genetic diversity. Seed production areas (SPAs) can help to reduce the burden of collecting native seed from remnant vegetation, improve genetic diversity in managed seed crops and contribute to species conservation. Banksia marginata (Proteaceae) is a key restoration species in south-eastern Australia but is highly fragmented and declining across much of its range. We evaluated genetic diversity, population genetic structure and relatedness in two B. marginata SPAs and the wild populations from which the SPA germplasm was sourced. We found high levels of relatedness within most remnants and that the population genetic structure was best described by three groups of trees. We suggest that SPAs are likely to be important to meet future native seed demand but that best practice protocols are required to assist land managers design and manage these resources including genetic analyses to guide the selection of germplasm.

The bulk of Earth’s biological materials consist of few base substances—essentially proteins, polysaccharides, and minerals—that assemble into large varieties of structures. Multifunctionality arises naturally from this structural complexity: An example is the combination of rigidity and flexibility in protein-based teeth of the squid sucker ring. Other examples are time-delayed actuation in plant seed pods triggered by environmental signals, such as fire and water, and surface nanostructures that combine light manipulation with mechanical protection or water repellency. Bioinspired engineering transfers some of these structural principles into technically more relevant base materials to obtain new, often unexpected combinations of material properties. Less appreciated is the huge potential of using bioinspired structural complexity to avoid unnecessary chemical diversity, enabling easier recycling and, thus, a more sustainable materials economy. [ABSTRACT FROM AUTHOR]

Identification of pollen vectors is a fundamental objective of pollination biology. The foraging and social behavior of these pollinators has profound effects on plant mating, making quantification of their behavior critical for understanding the ecological and evolutionary consequences of different pollinators for the plants they visit. However, accurate quantification of visitation may be problematic, especially for shy animals and/or when the temporal and spatial scale of observation desired is large. Sophisticated heat‐ and movement‐triggered motion‐sensor cameras ("camera trapping") provide new, underutilized tools to address these challenges. However, to date, there has been no rigorous evaluation of the sampling considerations needed for using camera trapping in pollination research.We measured the effectiveness of camera trapping for identifying vertebrate visitors and quantifying their visitation rates and foraging behavior on Banksia menziesii (Proteaceae). Multiple still cameras (Reconyx HC 500) and a video camera (Little Acorn LTL5210A) were deployed.From 2,753 recorded visits by vertebrates, we identified five species of nectarivorous honeyeater (Meliphagidae) and the honey possum (Tarsipedidae), with significant variation in the species composition of visitors among inflorescences. Species of floral visitor showed significant variation in their time of peak activity, duration of visits, and numbers of flowers probed per visit. Where multiple cameras were deployed on individual inflorescences, effectiveness of individual still cameras varied from 15% to 86% of all recorded visits. Methodological issues and solutions, and the future uses of camera traps in pollination biology, are discussed.Conclusions and wider implications: Motion‐triggered cameras are promising tools for the quantification of vertebrate visitation and some aspects of behavior on flowers. However, researchers need to be mindful of the variation in effectiveness of individual camera traps in detecting animals. Pollinator studies using camera traps are in their infancy, and the full potential of this developing technology is yet to be realized. Camera trapping provides a new and underutilised tool for identifying and quantifying the behaviour of vertebrate pollinators on flowers. We conduct a first rigorous assessment of the effectiveness of camera trapping for pollination studies. We identify methodological issues and solutions, and discuss the future potential of camera traps in pollination biology. [ABSTRACT FROM AUTHOR]

Gene flow is a critical component of plant mating systems and influences population fitness. However, pollen dispersal can be highly variable and influenced by natural and anthropogenic fragmentation. Gene flow through pollen dispersal was investigated in two populations of contrasting size and habitat context in Banksia nivea ssp. uliginosa, a rare species in the Busselton ironstone threatened ecological community of Western Australia with a naturally fragmented distribution. Paternity analysis was conducted with seven microsatellite loci to determine mating system parameters and patterns of pollen dispersal. Outcrossing was high in both populations with a similar level of selfing for both populations despite differences in population size, density and vegetation matrix. Most mating occurred within 10 m of a mother plant in the small, clumped population, while more dispersed mating, up to 50 m from a mother plant, was recorded in the large, less dense population. Our results show that population density and size are important influences on mating system parameters and level of pollen dispersal. [ABSTRACT FROM AUTHOR]

Bees require floral resources in the form of pollen and nectar for food but, in addition, many cavity-nesting species require other plant resources for nesting materials, which might come from plants on which they do not forage for food. This paper records the habitual use of dry flowers and indumentum from tomentose floral bracts of Banksia as nesting material by the Australian megachilid bee Megachile ignita Smith, which appears to be characteristic of this species. Additional aspects of its nesting biology are discussed, including phenology, number of brood cells per nest, mortality rate, sex ratio, body size and infestation of nests by parasitoid wasps. [ABSTRACT FROM AUTHOR]

Species distribution models can be informative of the biodiversity impacts of changing environments at global, national, and regional scales, but are often constrained in their resolution to extents not relevant to individual, intensive ecological management programs. We constructed a high‐resolution topoclimatic model of spring and summer temperatures across a 152 km2 restoration area on the Swan Coastal Plain, Western Australia, and used it to project energetic expenditure and habitat suitability estimates for four major hymenopteran pollinators. For all species, the most heavily modified landscapes were the least suitable, but only for one species, Zapsilothynnus nigripes, was there evidence that the upper thermal tolerance threshold was exceeded broadly. However, at the higher environmental temperatures that we modeled, some species would need to forage up to 10 times their own body mass every hour to meet their energetic requirements. It seems unlikely that the nutritional requirements of most insect pollinators operating at these higher metabolic rates could be met in an impoverished restoration ecosystem, although resource availability remains to be quantified in these habitats. Hence, to increase the likelihood of restoration success by restoring insect pollination networks, nutritional resources may need to be increased during restoration. Accounting for the way that thermoenergetic requirements shape ecological interactions better positions management trajectories aimed at restoring and maintaining key insect pollinators in “novel” ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Heat‐triggered fruit opening and delayed release of mature seeds are widespread among plants in fire‐prone ecosystems. Here, the material characteristics of the seed‐containing follicles of Banksia attenuata (Proteaceae), which open in response to heat frequently caused by fire, are investigated. Material analysis reveals that long‐term dimensional stability and opening temperatures of follicles collected across an environmental gradient increase as habitats become drier, hotter, and more fire prone. A gradual increase in the biaxial curvature of the hygroscopic valves provides the follicles in the driest region with the highest flexural rigidity. The irreversible deformation of the valves for opening is enabled via a temperature‐dependent reduction of the elastic modulus of the innermost tissue layer, which then allows releasing the stresses previously generated by shrinkage of the fiber bundles in the adjacent layer during follicle drying. These findings illustrate the level of sophistication by which this species optimizes its fruit opening mechanism over a large distribution range with varying environmental conditions, and may not only have great relevance for developing biomimetic actuators, but also for elucidating the species' capacity to cope with climatic changes. [ABSTRACT FROM AUTHOR]

We describe microhabitat use and response to disturbance by the eastern pygmy-possum (Cercartetus nanus) in heathy dry sclerophyll forest using spool-and-line-tracking. We compared unlogged forest with forest regenerating four years after selective logging. Structural and floristic attributes were scored along spool lines and compared with a random line for each possum. We found that possums (n = 23) selected areas based on both structural and floristic attributes. Possums selected dense understorey, especially that comprising flowering hairpin banksia (Banksia spinulosa) and Gymea lily (Doryanthes excelsa). Fallen logs were not selected by nocturnally active possums. Spool lines in regrowth forest had less eucalypt cover and more understorey cover (e.g. D. excelsa and B. spinulosa) than unlogged forest. Conversely, cover of Banksia serrata was less in regrowth than unlogged forest. Spool lines were commonly found both at ground level (mean = 52-57% of lengths) and above the ground (43-48% of lengths). There was no difference in the mean spool height between the logging treatments (regrowth: 0.47 ± 0.14 m; unlogged: 0.49 ± 0.10 m; ± s.e.). Overall, our results suggest that the dense, flowering understorey that regenerates after selective logging is suitable for use and is the primary attribute selected by active pygmy-possums. [ABSTRACT FROM AUTHOR]