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Changes to body size and shape have been identified as potential adaptive responses to climate change, but the pervasiveness of these responses has been questioned. To address this, we measured body and appendage size from 5013 museum bird skins of 78 ecologically and evolutionary diverse Australian species. We found that morphological change is a shared response to climate change across birds. Birds increased relative bill surface area, tarsus length, and relative wing length through time, consistent with expectations of increasing appendage size as climates warm. Furthermore, birds decreased in absolute wing length, consistent with the expectation of decreasing body size in warmer climates. Interestingly, these trends were generally consistent across different diets and migratory and thermoregulatory behaviors. Shorter term responses to higher temperatures were contrary to long‐term effects for appendages, wherein relative appendage size decreased after hotter years, indicating the complex selective pressures acting on birds as temperatures rise with climate change. Overall, our findings support the notion that morphological adaptation is a widespread response to climate change in birds that is independent of other ecological traits. [ABSTRACT FROM AUTHOR]

Understanding variation in trait allometry and the drivers of variation in sexually selected traits is a major theme in evolutionary biology. The static allometries of sexually selected traits are often positive due to disproportional investment by large individuals into trait size. Comparative studies of weapon allometry are rare, and typically focus on variation along a single dimension (e.g. length), despite weapons often diverging dramatically in shape. Furthermore, studies predominantly focus on groups where weapons have evolved as novel structures (e.g. horns), despite most weapons arising from modifications of existing structures.We test the hypothesis that sexual selection drives variation in static allometry using a phylogenetic comparative approach with 59 brentine weevil species showing remarkable variation in trait exaggeration and sexual size dimorphism (SSD).Contrasting two dimensions of head size exaggeration (a sexually selected trait) and elytron length (a nonsexual trait), positive static allometry was common across both measures of male head size, but not females, and there was positive covariance between male head static allometry and SSD across species. Positive static allometry for male elytron length was less common, but did show positive covariance with SSD, possibly due to the function of wings as compensatory structures for bearing large weapons.Our findings support the hypothesis that sexual selection drives the evolution of allometries both within and among species, and that the modification of existing structures to be used as weapons does not limit the potential for positive static allometry. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Morphology is integral to body temperature regulation. Recent advances in understanding of thermal physiology suggest a role of the avian bill in thermoregulation. To explore the adaptive significance of bill size for thermoregulation we characterized relationships between bill size and climate extremes. Most previous studies focused on climate means, ignoring frequencies of extremes, and do not reflect thermoregulatory costs experienced over shorter time scales. Using 79 species (9847 museum specimens), we explore how bill size variation is associated with temperature extremes in a large and diverse radiation of Australasian birds, Meliphagides, testing a series of predictions. Overall, across the continent, bill size variation was associated with both climate extremes and means and was most strongly associated with winter temperatures; associations at the level of climate zones differed from continent-wide associations and were complex, yet consistent with physiology and a thermoregulatory role for avian bills. Responses to high summer temperatures were nonlinear suggesting they may be difficult to detect in large-scale continental analyses using previous methodologies. We provide strong evidence that climate extremes have contributed to the evolution of bill morphology in relation to thermoregulation and show the importance of including extremes to understand fine-scale trait variation across space. [ABSTRACT FROM AUTHOR]

Institutes of higher learning are tending to reduce the amount of face-to-face teaching that they offer, and particularly through the traditional pedagogical method of lecturing. There is ongoing debate about the educational value of lectures as a teaching approach, in terms of both whether they facilitate understanding of subject material and whether they augment the student educational experience. In this study, student evaluation of teaching scores plus academic outcome (percentage of students who fail) was assessed for 236 course units offered by a science faculty at an Australian university over the course of one year. These measures were related to the degree to which lectures and other face-to-face teaching were used in these units, controlling for factors such as class size, school and year level. An information-theoretic model selection approach was employed to identify the best models and predictors of student assessments and fail rates. All the top models of student feedback included a measure reflecting amount of face-to-face teaching, with the evaluation of quality of teaching being higher in units with higher proportions of lectures. However, these models explained only 12-20% of the variation in student evaluation scores, suggesting that many other factors come into play. By contrast, units with fewer lectures have lower failure rates. These results suggest that moving away from lectures and face-to-face teaching may not harm, and indeed may improve the number of students who pass the subject, but that this may be incurred at the expense of greater dissatisfaction in students' learning experience.

War influences wildlife in a variety of ways but may influence their escape responses to approaching threats, including humans, because of its effect on human populations and behavior and landscape change. We collected 1,400 flight initiation distances (FIDs) from 157 bird species in the dry zone of Sri Lanka, where civil war raged for 26 years, ending in 2009. Accounting for factors known to influence FIDs (phylogeny, starting distance of approaches, body mass, prevailing human density, group size, and location), we found that birds have longer FIDs in the part of the dry zone that experienced civil war. Larger birds—often preferred by human hunters—showed greater increases in FID in the war zone, consistent with the idea that war was associated with greater hunting pressure and that larger birds experienced longer-lasting trauma or had more plastic escape behavior than smaller species. While the mechanisms linking the war and avian escape responses remain ambiguous, wars evidently leave legacies that extend to behavioral responses in birds. [ABSTRACT FROM AUTHOR]

Abstract Background During evolution, plants and other organisms have developed a diversity of chemical defences, leading to the evolution of various groups of specialized metabolites selected for their endogenous biological function. A correlation between phylogeny and biosynthetic pathways could offer a predictive approach enabling more efficient selection of plants for the development of traditional medicine and lead discovery. However, this relationship has rarely been rigorously tested and the potential predictive power is consequently unknown. Results We produced a phylogenetic hypothesis for the medicinally important plant subfamily Amaryllidoideae (Amaryllidaceae) based on parsimony and Bayesian analysis of nuclear, plastid, and mitochondrial DNA sequences of over 100 species. We tested if alkaloid diversity and activity in bioassays related to the central nervous system are significantly correlated with phylogeny and found evidence for a significant phylogenetic signal in these traits, although the effect is not strong. Conclusions Several genera are non-monophyletic emphasizing the importance of using phylogeny for interpretation of character distribution. Alkaloid diversity and in vitro inhibition of acetylcholinesterase (AChE) and binding to the serotonin reuptake transporter (SERT) are significantly correlated with phylogeny. This has implications for the use of phylogenies to interpret chemical evolution and biosynthetic pathways, to select candidate taxa for lead discovery, and to make recommendations for policies regarding traditional use and conservation priorities.

Wetlands, and the species that rely upon them, are under significant threat world‐wide, with wetlands often being completely removed or drastically altered. Successful wetland management requires an understanding of the interactions between wetland species and the microhabitats they use. The use of microhabitats for thermoregulation in wetland species is poorly studied, though anthropogenic influence on wetlands can reduce the diversity of microhabitats and thus the thermoregulatory options for animals. At high ambient temperatures birds may use the water‐logged wetland margins to help with thermoregulation, and are often observed roosting in the sitting position within this microhabitat. However, whether sitting on the wet substrate helps in thermoregulation is unknown.In this study, we tested whether birds selectively use microhabitats across temperatures by conducting field observations of nine species of shorebirds. We use comparative analysis to determine whether birds roost more on wet substrate in the sitting posture, that is, 'wet‐sitting', at high ambient temperatures.We found substrate type across the wetland margins to be important in shorebird thermoregulation, with the time spent sitting being significantly mediated by the substrate on which the bird roosted. Individuals tended to sit on bare, wet ground much more under high ambient temperatures compared with low ambient temperatures. Vegetation on the other hand was used similarly across temperatures, and likely does not provide the same thermoregulatory benefits.By roosting on wet substrate at high ambient temperatures, birds may increase the potential for heat dissipation across the uninsulated legs, as water‐logged wetland margins are known to remain cooler than the ambient temperature or vegetated microhabitats under hot climatic conditions.Synthesis and applications. Wetland creation and management requires an understanding of the functional significance of such microhabitats, not only for foraging and breeding, but also for roosting. We demonstrate that managing wetland margins is likely important in minimising heat stress in birds, with our findings emphasising the importance of maintaining open spaces in habitat mosaics for birds to use for thermoregulation. The ability of wetland species to manage heat stress is becoming exceedingly important as they are threatened by both decreased wetland availability and increasing ambient temperatures under climate change. [ABSTRACT FROM AUTHOR]

At the continental scale, ecological research effort is not spatially uniform. We used a century-long bibliometric database of the journal Emu – Austral Ornithology to index the spatial patterns in bird research in Australia (from articles with explicit study locations). Studies have been concentrated in Tasmania and the southwest, southeast and coastal parts of the mainland. Large spatial gaps exist in ornithological study, which are similar to those identified by Arnold Robert McGill in his 1948 review paper (McGill 1948). Pre-1948 only 9.4% of articles [n = 2,107] fell within the gaps mapped by McGill in 1948, indicating that his mapping was largely accurate. These gaps have largely persisted; only 11.2% of the 1,498 articles published since 1948 came from within those gaps. We present a complementary spatial gap analysis, which focuses on studies of areas with broadly similar biogeographies (Interim Biogeographical Regions of Australia (IBRAs)). Of 85 mainland IBRAs (of 89 defined), five have no bird studies from within them (368,380 km2; 4.9% of Australia), and 34 have less than 10 studies (3,335,498 km2; 43.9%). We intersect IBRAs with McGill's gaps and show that some IBRAs within McGill's gaps are now better-studied, but 64.8% of the area within the McGill gaps boundaries comprises IBRAs where there have been no post-1948 studies in Emu. We also present an updated map of key geographical gaps in the study of Australian birds, which apparently remain extensive 60 years after they were first identified. [ABSTRACT FROM AUTHOR]

Allen's rule is an ecogeographical pattern whereby the size of appendages of animals increases relative to body size in warmer climates in order to facilitate heat exchange and thermoregulation. Allen's rule predicts that one consequence of a warming climate would be an increase in the relative size of appendages, and evidence from other bird species suggests that this might be occurring. Using measurements from museum specimens, we determined whether spatio-temporal variation in bills and legs of Australian Pachycephalidae species exhibits within-species trends consistent with Allen's rule and increases in temperature attributable to climatic warming. We conducted regression model analyses relating appendage size to spatio-temporal variables, while controlling for body size. The relative bill size in four of the eight species was negatively associated with latitude. Tarsus length showed no significant trends consistent with Allen's rule. No significant increases in appendage size were found over time. Although bill size in some species was positively correlated with warmer temperatures, the evidence was not substantial enough to suggest a morphological response to climatic warming. This study suggests that climate change is not currently driving adaptive change towards larger appendages in these species. We suggest that other adaptive mechanisms might be taking place. [ABSTRACT FROM AUTHOR]

Advances in human technology can lead to widespread and rapid increases in interactions between wildlife and potentially disturbing stimuli. The recreational use of drones is widespread and increasing, yet laws and codes of practice which aim to manage deleterious impacts (e.g. negative interactions with wildlife) are reactionary, unscientific and inadequate.One prominent potential negative effect of drones interacting with birds is disturbance; the disruption of normal states caused by responses such as escape. We measure avian escape responses to an approaching drone (n = 561 across 22 species) to inform the development of a code of practice to manage drone‐induced disturbance. Approaches were made at a relatively high and low altitude (10 and 4 m), and at different take‐off distances, both of which are candidate prescriptions for a code of practice.Flight‐initiation distance varied between species, but not between the altitudes tested. The probability of eliciting an escape response was high, and 14.6% higher at the lower altitude (at which 88.4% of overflies resulted in an escape response). Our response rates (from terrestrial and aquatic species) are higher than those reported for different birds in other places, most of which were water or seabirds.The probability of a drone take‐off in itself eliciting a response was low (<20%) when the drone take‐off was >40 m away, and decreased further with increasing distance from birds, with no escapes occurring >120 m.Policy implications. For our sample, no drone take‐off closer than 100 m, and no flight within 100 m would eliminate the vast majority of escape responses by birds. Required separation distances between drones and wildlife may exceed those required for other human activities, such as for walkers. [ABSTRACT FROM AUTHOR]

Varying forms of polygyny are observed across many animal groups. In some species, groups of females may remain with a single male for an extended length of time. This is often referred to as harem polygyny. A female‐biased sex ratio has been associated with harem polygynous species. In such species, formation of harems may be an inevitable consequence of the relative lack of available males, rather than multiple females actively choosing to mate with a subset of specific males. The five‐spined bark beetle, Ips grandicollis, is a secondary pest of pine plantations (Pinus spp.). Harem‐like groups are formed when males bore into the bark creating a small nuptial chamber from where they release pheromones, attracting multiple females that build individual galleries associated with the males' chamber. We estimated the sex ratio of I. grandicollis in the flying population compared with those in the logs, and investigated whether females are actively choosing to join the harem of particular males, or if they simply randomly allocate themselves to harems. We also investigated how this female behaviour changes over time since the start of colonisation. The sex ratio in the flying population of I. grandicollis was slightly male biased while the population in pine billets was female biased. Early colonising females (within 2 to 8 days of log infestation) joined males non‐randomly – being more evenly distributed than expected by chance. However, the pattern of allocation differs between these days, with females allocating themselves more randomly later in the colonisation process. In a separate experiment, data collected from logs colonised after 14 days suggest completely random allocation of females to males. These results suggest that when there is a higher proportion of males to females (during early colonisation), females allocate themselves evenly among males, reducing potential between‐female competition. However, as males become rarer, females must join larger harems, but do not appear to exhibit any specific choice behaviour in which harems they join. [ABSTRACT FROM AUTHOR]

One of the most conspicuous features of many moth species is their antennae, which can be strikingly elaborate. However, the factors that have influenced the evolution of these impressive receptor organs remain poorly known. Antennae are potentially costly structures, and previous research has indicated that investment in these structures may be traded‐off against investment in other organs, depending on the mating strategy in which individuals engage. Using a phylogenetic comparative analysis of data from dissected wild‐caught individuals from 44 Australian moth species, we examined potential trade‐offs and correlations between antennal size (measured as antenna length and antenna area) and the size of a range of other morphological features related to paternity (testis area), and vision (eye diameter). Antenna area did not show any evidence of a trade‐off with testis size (area) after controlling for body size and phylogeny. Further, relative antenna length was positively correlated with relative eye size, suggesting that investment in both sensory structures is linked. Analysis of the allometric scaling of antennal size and eye diameter found that larger moth species invested relatively more in the size of their male antennae (both area and length) than in the size of their eyes. These results indicate different patterns of investment in sensory structures in relation to body size, with larger moth species favouring the evolution of more elaborate antennae in males. [ABSTRACT FROM AUTHOR]

Many animals undergo complete metamorphosis, where larval forms change abruptly in adulthood. Color change during ontogeny is common, but there is little understanding of evolutionary patterns in these changes. Here, we use data on larval and adult color for 246 butterfly species (61% of all species in Australia) to test whether the evolution of color is coupled between life stages. We show that adults are more variable in color across species than caterpillars and that male adult color has lower phylogenetic signal. These results suggest that sexual selection is driving color diversity in male adult butterflies at a broad scale. Moreover, color similarities between species at the larval stage do not predict color similarities at the adult stage, indicating that color evolution is decoupled between young and adult forms. Most species transition from cryptic coloration as caterpillars to conspicuous coloration as adults, but even species with conspicuous caterpillars change to different conspicuous colors as adults. The use of high‐contrast coloration is correlated with body size in caterpillars but not adults. Taken together, our results suggest a change in the relative importance of different selective pressures at different life stages, resulting in the evolutionary decoupling of coloration through ontogeny. [ABSTRACT FROM AUTHOR]

Research effort is not uniform among bird species and may be influenced by multiple biological and environmental factors. Using a phylogenetic comparative approach we examined how research effort into Australian birds is related to phylogeny and tested whether key aspects of species' biology influence this research effort. We quantified research effort directed at Australian birds by using a bibliometric dataset on 100 years of publications in the journal Emu. We found significant phylogenetic signal in research effort with bias towards the orders Passeriformes, Procellariiformes (seabirds), Cuculiformes (cuckoos), Struthioniformes (Emu and Cassowary) and Sphenisciformes (penguins). By contrast Columbiformes (doves and pigeons), Gruiformes (e.g. rails) and Turniciformes (button-quail) are, as a whole, under-studied. Further, we found several significant biological predictors of research effort. There has been a greater number of studies on species with larger body sizes, broader ranges, higher relative abundance (reporting rate), and that are found in urban environments - all characteristics that are likely to make them more obvious and accessible. We conclude that, in a continent with a relatively low density of ornithologists and many areas which are difficult to access, species that are encountered more readily are more likely to be studied. This pattern renders smaller, range-restricted species inhabiting remote areas more likely to experience the difficulties associated with data deficiency. Some or many of these species may have more perilous conservation statuses than currently recognised. [ABSTRACT FROM AUTHOR]

The Australian arid zone is well recognised as a source of evolutionary novelty and diversity. Roles for selection vs. drift in the region remain less understood. We surveyed mitogenomic diversity and genome-wide nuclear markers in the Mulga Parrot (Psephotellus varius) to add to phylogeographic data from arid zone species. We found structured diversity either side of the Flinders Ranges–Lake Eyre Basin (Eyrean barrier; net nucleotide divergence 1.92% forND2). Coalescent analysis suggests that this arose during the mid-Pleistocene approximately 402 000 years ago. In both phylogroups, however, the mitogenome is under pervasive purifying selection. Purifying selection in the context of consistent environments either side of the Eyrean barrier may have maintained ancestral plumage and morphological traits, though in other plumage traits there is some plumage divergence that is geographically concordant with the phylogeographic structure. This leads to the essentially ‘cryptic’ genetic diversity uncovered here, despite indications of ongoing adaptation to aridity inP. variusas evidenced by increasing bill surface area (shown by earlier work to have increased relative to body size by 10.4% since 1871), a result we affirm here across the species as a whole. This study also demonstrates the utility of shallow ‘genome skimming’ sequencing for population analyses. [ABSTRACT FROM PUBLISHER]

ABSTRACT The avian bill is a textbook example of how evolution shapes morphology in response to changing environments. Bills of seed-specialist finches in particular have been the focus of intense study demonstrating how climatic fluctuations acting on food availability drive bill size and shape. The avian bill also plays an important but under-appreciated role in body temperature regulation, and therefore in energetics. Birds are endothermic and rely on numerous mechanisms for balancing internal heat production with biophysical constraints of the environment. The bill is highly vascularised and heat exchange with the environment can vary substantially, ranging from around 2% to as high as 400% of basal heat production in certain species. This heat exchange may impact how birds respond to heat stress, substitute for evaporative water loss at elevated temperatures or environments of altered water availability, or be an energetic liability at low environmental temperatures. As a result, in numerous taxa, there is evidence for a positive association between bill size and environmental temperatures, both within and among species. Therefore, bill size is both developmentally flexible and evolutionarily adaptive in response to temperature. Understanding the evolution of variation in bill size however, requires explanations of all potential mechanisms. The purpose of this review, therefore, is to promote a greater understanding of the role of temperature on shaping bill size over spatial gradients as well as developmental, seasonal, and evolutionary timescales. [ABSTRACT FROM AUTHOR]

For dioecious animals, reproductive success typically involves an exchange between the sexes of signals that provide information about mate location and quality. Typically, the elaborate, secondary sexual ornaments of males signal their quality, while females may signal their location and receptivity. In theory, the receptor structures that receive the latter signals may also become elaborate or enlarged in a way that ultimately functions to enhance mating success through improved mate location. The large, elaborate antennae of many male moths are one such sensory structure, and eye size may also be important in diurnal moths. Investment in these traits may be costly, resulting in trade-offs among different traits associated with mate location. For polyandrous species, such trade-offs may also include traits associated with paternity success, such as larger testes. Conversely, we would not expect this to be the case for monandrous species, where sperm competition is unlikely. We investigated these ideas by evaluating the relationship between investment in sensory structures (antennae, eye), testis, and a putative warning signal (orange hindwing patch) in field-caught males of the monandrous diurnal painted apple moth Teia anartoides (Lepidoptera: Lymantriidae) in southeastern Australia. As predicted for a monandrous species, we found no evidence that male moths with larger sensory structures had reduced investment in testis size. However, contrary to expectation, investment in sensory structures was correlated: males with relatively larger antennae also had relatively larger eyes. Intriguingly, also, the size of male orange hindwing patches was positively correlated with testis size. [ABSTRACT FROM AUTHOR]

Background: Aloe vera supports a substantial global trade yet its wild origins, and explanations for its popularity over 500 related Aloe species in one of the world's largest succulent groups, have remained uncertain. We developed an explicit phylogenetic framework to explore links between the rich traditions of medicinal use and leaf succulence in aloes. Results: The phylogenetic hypothesis clarifies the origins of Aloe vera to the Arabian Peninsula at the northernmost limits of the range for aloes. The genus Aloe originated in southern Africa ~16 million years ago and underwent two major radiations driven by different speciation processes, giving rise to the extraordinary diversity known today. Large, succulent leaves typical of medicinal aloes arose during the most recent diversification ~10 million years ago and are strongly correlated to the phylogeny and to the likelihood of a species being used for medicine. A significant, albeit weak, phylogenetic signal is evident in the medicinal uses of aloes, suggesting that the properties for which they are valued do not occur randomly across the branches of the phylogenetic tree. Conclusions: Phylogenetic investigation of plant use and leaf succulence among aloes has yielded new explanations for the extraordinary market dominance of Aloe vera. The industry preference for Aloe vera appears to be due to its proximity to important historic trade routes, and early introduction to trade and cultivation. Well-developed succulent leaf mesophyll tissue, an adaptive feature that likely contributed to the ecological success of the genus Aloe, is the main predictor for medicinal use among Aloe species, whereas evolutionary loss of succulence tends to be associated with losses of medicinal use. Phylogenetic analyses of plant use offer potential to understand patterns in the value of global plant diversity. [ABSTRACT FROM AUTHOR]

We use a simulation model to examine four of the most common hypotheses for the latitudinal richness gradient and identify patterns that might be diagnostic of those four hypotheses. The hypotheses examined include (1) tropical niche conservatism, or the idea that the tropics are more diverse because a tropical clade origin has allowed more time for diversification in the tropics and has resulted in few species adapted to extratropical climates. (2) The ecological limits hypothesis suggests that species richness is limited by the amount of biologically available energy in a region. (3) The speciation rates hypothesis suggests that the latitudinal gradient arises from a gradient in speciation rates. (4) Finally, the tropical stability hypothesis argues that climatic fluctuations and glacial cycles in extratropical regions have led to greater extinction rates and less opportunity for specialization relative to the tropics. We found that tropical niche conservatism can be distinguished from the other three scenarios by phylogenies which are more balanced than expected, no relationship between mean root distance (MRD) and richness across regions, and a homogeneous rate of speciation across clades and through time. The energy gradient, speciation gradient, and disturbance gradient scenarios all produced phylogenies which were more imbalanced than expected, showed a negative relationship between MRD and richness, and diversity-dependence of speciation rate estimates through time. We found that the relationship between speciation rates and latitude could distinguish among these three scenarios, with no relation expected under the ecological limits hypothesis, a negative relationship expected under the speciation rates hypothesis, and a positive relationship expected under the tropical stability hypothesis. We emphasize the importance of considering multiple hypotheses and focusing on diagnostic predictions instead of predictions that are consistent with multiple hypotheses. [ABSTRACT FROM AUTHOR]

Increased encephalization has been linked to a range of behavioural traits and scenarios. However, studies of whole brain size in this context have been criticised for ignoring the role of specific brain areas in controlling behaviour. In birds, the response to potential threats is one such behaviour that may relate to the way in which the brain processes sensory information. We used a phylogenetic generalised least squares (PGLS) analyses, based on five different phylogenetic hypotheses, to analyse the relationship of relative sizes of whole brain and brain components with Flight-Initiation Distance (FID), the distance at which birds flee from an approaching human, for 41 bird species. Starting distance (the distance at which an approach to a bird commences), body mass and eye size have elsewhere been shown to be positively associated with FID, and consequently were included as covariates in our analysis. Starting distance and body mass were by far the strongest predictors of FID. Of all brain components, cerebellum size had the strongest predictor weight and was negatively associated with FID but the confidence intervals on the average estimate included zero and the overall predictor weight was low. Models featuring individual brain components were generally more strongly weighted than models featuring whole brain size. The PGLS analyses estimated there to be no phylogenetic signal in the regression models, and hence produced results equivalent to ordinary least squares regression analysis. However analyses that assumed strong phylogenetic signal produced substantially different results with each phylogeny, and overall suggest a negative relationship between forebrain size and FID. Our analyses suggest that the evolutionary assumptions of the comparative analysis, and consideration of starting distance make a profound difference to the interpretation of the effect of brain components on FID in birds. [ABSTRACT FROM AUTHOR]

In many animals, response to predators occurs at greater distances the further an individual is from a refuge, but this has rarely been investigated in birds. Here, we test the hypothesis that the further from refuge (i.e. water) a foraging black swan Cygnus atratus is situated, the longer its flight initiation distance ( FID) in response to a pedestrian approach on land. As predicted, swans situated farther from water exhibited longer FIDs compared with those closer to the shore. In addition, there was the possibility of an interesting interaction effect (p < 0.061) of sex and direction of approach on FID. Whilst males tended to not alter their response in relation to the angle of approach relative to the water, females tended to respond at longer distances, when approached from the shore than when approached from the land or parallel to the shore. This is one of the first reports of sex differences in FIDs for birds, with sex differences only manifesting themselves under certain approach types. Group size, the order of repeated approaches, and time of day did not influence responses, although starting distance of approach was positively related to FID. [ABSTRACT FROM AUTHOR]

Identifying general patterns of adaptive coloration in animals can help to elucidate the evolutionary processes that generate them. We examined the evolution of colour patterns in Australian agamid lizards, a morphologically and ecologically diverse group that relies primarily on visual communication. We tested whether certain types of colour (yellow-reds and black) were likely to be used as sexual signals, as indicated by their association with indices of sexual selection, namely, sexual dichromatism and sexual dimorphism in body size and head shape. We then tested whether sexually dichromatic colours are associated with specific patterns (uniform, mottled, striped, blotched, reticulated) or ecological variables such as habitat openness, arboreality, and substrate type. The presence of yellow-red on lateral and ventral body regions and black on ventral body regions was significantly more common in males than females. Lateral yellow-red in males was associated with the total extent of sexual dichromatism and size dimorphism, whereas ventral yellow-red was associated with sexual dichromatism. Both lateral and ventral yellow-red were associated with uniform patterning, suggesting that sexual signals in male agamid lizards may often comprise uniform patches or flushes of yellow-red. Although ventral black coloration was more prevalent on males (i.e. strongly sexually dichromatic), it was not associated with indices of sexual selection, suggesting that, in agamid lizards, yellow-red coloration is more likely to be sexually selected than black. Sexually dichromatic coloration was not strongly associated with any of the ecological variables measured. We found some associations, however, between female dorsal patterns and ecological variables, suggesting that female patterns are influenced by natural selection. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109, 101-112. [ABSTRACT FROM AUTHOR]

Environmental factors may affect chemical communication between individuals by limiting their ability to detect and respond to these signals. One such factor, high humidity, has been shown to interfere with the normal response of some invertebrate species to their attractant pheromones. The effect of humidity on the response of the five-spined bark beetle, Ips grandicollis, to a synthetic form of the aggregation pheromone component ipsenol, was tested in an experimental chamber in the laboratory. The response was measured as both the number of beetles to reach the pheromone source and the time taken, and was tested under high (>80% relative humidity) and low (30-40% relative humidity) conditions of humidity. There was no significant difference in response of beetles between the two treatments although there was a reduction in response in the high-humidity treatment when relative humidity levels were in excess of 90%. These findings suggest that atmospheric humidity does not influence bark beetles response to synthetic pheromone, except perhaps in unlikely conditions of excessive humidity. [ABSTRACT FROM AUTHOR]

Recent developments in ecological statistics have reached behavioral ecology, and an increasing number of studies now apply analytical tools that incorporate alternatives to the conventional null hypothesis testing based on significance levels. However, these approaches continue to receive mixed support in our field. Because our statistical choices can influence research design and the interpretation of data, there is a compelling case for reaching consensus on statistical philosophy and practice. Here, we provide a brief overview of the recently proposed approaches and open an online forum for future discussion (https://bestat.ecoinformatics.org/). From the perspective of practicing behavioral ecologists relying on either correlative or experimental data, we review the most relevant features of information theoretic approaches, Bayesian inference, and effect size statistics. We also discuss concerns about data quality, missing data, and repeatability. We emphasize the necessity of moving away from a heavy reliance on statistical significance while focusing attention on biological relevance and effect sizes, with the recognition that uncertainty is an inherent feature of biological data. Furthermore, we point to the importance of integrating previous knowledge in the current analysis, for which novel approaches offer a variety of tools. We note, however, that the drawbacks and benefits of these approaches have yet to be carefully examined in association with behavioral data. Therefore, we encourage a philosophical change in the interpretation of statistical outcomes, whereas we still retain a pluralistic perspective for making objective statistical choices given the uncertainties around different approaches in behavioral ecology. We provide recommendations on how these concepts could be made apparent in the presentation of statistical outputs in scientific papers. [ABSTRACT FROM PUBLISHER]