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We describe a new species of smoky honeyeater from the Foja Mountains, an isolated range in western New Guinea (Papua Province, Indonesia). A common inhabitant of montane forest and forest-edge in this little-known north coastal range, this species possesses a fleshy pendant suborbital wattle, unique in the genus Melipotes, among other characteristics that distinguish it from all congeners. This fleshy wattle provides a morphological link between Melipotes and the monotypic genus Macgregoria, an alpine inhabitant of the Central Ranges of New Guinea, traditionally treated as a bird of paradise (e.g., Frith and Beehler 1998) but now regarded as the sister genus to Melipotes (Cracraft and Feinstein 2000). The presence of an endemic meliphagid species in the Foja Mountains highlights the biogeographic significance and conservation importance of this geographically isolated upland forest tract, which is also home to the endemic Golden-fronted Bowerbird (Amblyornis flavifrons) and Berlepsch's Parotia (Parotia berlepschi), a distinctive, recently rediscovered species of six-wired bird of paradise (B. M. Beehler unpubl. data).

Two new species of the genus Melinirmus Mey, 2017, are described from Australian honeyeaters (Meliphagidae). These are: Melinirmus coromandelica n. sp. ex Ptilotula penicillatus penicillatus (Gould, 1837) and Melinirmus palmai n. sp. ex Anthochaera carunculata (Shaw, 1790). A checklist of all known species of Brueelia-complex chewing lice known from the Meliphagidae is provided.

While morphological traits are often associated with multiple functions, it remains unclear how evolution balances the selective effects of different functions. Birds' beaks function not only in foraging but also in thermoregulating and singing, among other behaviours. Studies of beak evolution abound, however, most focus on a single function. Hence, we quantified relative contributions of different functions over an evolutionary timescale. We measured beak shape using geometric morphometrics and compared this trait with foraging behaviour, climatic variables and song characteristics in a phylogenetic comparative study of an Australasian radiation of songbirds (Meliphagidae). We found that both climate and foraging behaviour were significantly correlated with the beak shape and size. However, foraging ecology had a greater effect on shape, and climate had a nearly equal effect on size. We also found that evolutionary changes in beak morphology had significant consequences for vocal performance: species with elongate-shaped beaks sang at higher frequencies, while species with large beaks sang at a slower pace. The evolution of the avian beak exemplifies how morphological traits can be an evolutionary compromise among functions, and suggests that specialization along any functional axis may increase ecological divergence or reproductive isolation along others.

Honeyeaters (Aves, Meliphagidae) are a speciose clade of nectarivorous birds, and there is immense diversity in the degree to which different species within the family rely on nectar. Honeyeater tongues are commonly described as similar to a paintbrush, with this morphology being interpreted as an adaptation for increasing nectar extraction efficiency. However, there has been limited work documenting the degree of interspecific diversity in tongue morphology across the family or the extent to which such diversity correlates with dependance on nectar. This information is also lacking for the hyoid bones, the structures responsible for moving the tongue in and out of the mouth. We aimed to fill this knowledge gap by examining honeyeater tongues and hyoids from across the family. We found that there are six distinct tongue types across the Meliphagidae, and that certain genera such as Acanthorhynchus and Phylidonyris have a unique tongue morphologies. Using phylogenetic generalized least square regressions, we found that tongue length (not size corrected) and the proportion of tongue that is bristled were both positively correlated to degree of nectarivory, while tongue length (relative to bill length), tongue depth (relative to bill depth) and tongue width (relative to bill width) were not correlated to nectarivory. Finally, we found no correlation between hyoid length (relative to bill length) and nectarivory, suggesting that the capacity for further tongue protrusion is unrelated to nectar dependence in honeyeaters. Similar studies should be conducted across other groups of avian nectarivores to expand our understanding of dietary ecomorphology beyond bill shape, which has been the focus of the majority of research on food handling adaptations in birds thus far.

Aim: Among the world's three major nectar-feeding bird taxa, hummingbirds are the most phenotypically specialized for nectarivory, followed by sunbirds, while the honeyeaters are the least phenotypically specialized taxa. We tested whether this phenotypic specialization gradient is also found in the interaction patterns with their floral resources. Location: Americas, Africa, Asia and Oceania/Australia. Methods: We compiled interaction networks between birds and floral resources for 79 hummingbird, nine sunbird and 33 honeyeater communities. Interaction specialization was quantified through connectance (C), complementary specialization (H2′), binary (QB) and weighted modularity (Q), with both observed and null-model corrected values. We compared interaction specialization among the three types of bird–flower communities, both independently and while controlling for potential confounding variables, such as plant species richness, asymmetry, latitude, insularity, topography, sampling methods and intensity. Results: Hummingbird–flower networks were more specialized than honeyeater–flower networks. Specifically, hummingbird–flower networks had a lower proportion of realized interactions (lower C), decreased niche overlap (greater H2′) and greater modularity (greater QB). However, we found no significant differences between hummingbird– and sunbird–flower networks, nor between sunbird– and honeyeater–flower networks. Main conclusions: As expected, hummingbirds and their floral resources have greater interaction specialization than honeyeaters, possibly because of greater phenotypic specialization and greater floral resource richness in the New World. Interaction specialization in sunbird–flower communities was similar to both hummingbird–flower and honeyeater–flower communities. This may either be due to the relatively small number of sunbird–flower networks available, or because sunbird–flower communities share features of both hummingbird–flower communities (specialized floral shapes) and honeyeater–flower communities (fewer floral resources). These results suggest a link between interaction specialization and both phenotypic specialization and floral resource richness within bird–flower communities at a global scale.

Although the lethal consequences of extreme heat are increasingly reported in the literature, the fitness costs of exposure to sublethal high air temperatures, typically identified in the 30–40°C range, are poorly understood. We examine the effect of high (≥35°C) daily maxima on body condition of a semiarid population of White‐plumed Honeyeaters, Ptilotula penicillatus, monitored between 1986 and 2012. During this 26‐yr period, temperature has risen, on average, by 0.06°C each year at the site, the frequency of days with thermal maxima ≥35°C has increased and rainfall has declined. Exposure to high temperatures affected body condition of White‐plumed Honeyeaters, but only in low‐rainfall conditions. There was no effect of a single day of exposure to temperatures ≥35°C but repeated exposure was associated with reduced body condition: 3.0% reduction in body mass per day of exposure. Rainfall in the previous 30 d ameliorated these effects, with reduced condition evident only in dry conditions. Heat‐exposed males with reduced body condition were less likely to be recaptured at the start of the following spring; they presumably died. Heat‐exposed females, regardless of body condition, showed lower survival than exposed males, possibly due to their smaller body mass. The higher mortality of females and smaller males exposed to temperatures ≥35°C may have contributed to the increase in mean body size of this population over 23 years. Annual survival declined across time concomitant with increasing frequency of days ≥35°C and decreasing rainfall. Our study is one of few to identify a proximate cause of climate change related mortality, and associated long‐term demographic consequence. Our results have broad implications for avian communities living in arid and semiarid regions of Australia, and other mid‐latitudes regions where daily maximum temperatures already approach physiological limits in regions affected by both decreased precipitation and warming.

Quantifying the relationship between form and function can inform use of morphology as a surrogate for ecology. How the strength of this relationship varies continentally can inform understanding of evolutionary radiations; for example, does the relationship break down when certain lineages invade and diversify in novel habitats? The 75 species of Australian honeyeaters (Meliphagidae) are morphologically and ecologically diverse, with species feeding on nectar, insects, fruit, and other resources. We investigated Meliphagidae ecomorphology and community structure by (1) quantifying the concordance between morphology and ecology (foraging behavior), (2) estimating rates of trait evolution in relation to the packing of ecological space, and (3) comparing phylogenetic and trait community structure across the broad environmental gradients of the continent. We found that morphology explained 37% of the variance in ecology (and 62% vice versa), and we uncovered well-known bivariate relationships among the multivariate ecomorphological data. Ecological trait diversity declined less rapidly than phylogenetic diversity along a gradient of decreasing precipitation. We employ a new method (trait fields) and extend another (phylogenetic fields) to show that while species in phylogenetically clustered, arid-environment assemblages are similar morphologically, they are as varied in foraging behavior as those from more diverse assemblages. Thus, although closely related and similar morphologically, these arid-adapted species have diverged in ecological space to a similar degree as their mesic counterparts.

The Eastern spinebill (Acanthorhynchus tenuirostris), a passerine bird in the family Meliphagidae (honeyeaters), a dominant group of birds in Australia and New Guinea. The aim of this study was to sequence the complete mitochondrial genome of the Eastern spinebill and use its sequence to better define the phylogeny of this species. The complete mitogenome sequence of A. tenuirostris was circular and 16,614 bp in length, and its architecture was conserved in comparison to other mitogenome sequences under the family Meliphagidae. The Eastern spinebill mitogenome had the highest sequence identity with mitogenome sequences of two other honeyeaters, the white eared honeyeater, Nesoptilotis leucotis, (84.9%) and the white-plumed honeyeater, Ptilotula penicillata (85.5%). The maximum-likelihood topology distinctly discriminated the Eastern spinebill sequence against all other species of the Meliphagidae with significant bootstrap supports. We suggest the widespread sampling and complete mitogenome sequencing would be valuable in establishing the most accurate phylogenetic taxonomy of the family Meliphagidae.

Aim: Animal coloration often shows high degrees of evolutionary lability, producing variation among species that is easily apparent. This variation may produce consistent geographical patterns as species converge on adaptive phenotypes in similar environments. Some such geographical patterns in colour variation have been recently predicted as a response to the light environment in different habitats. Others like Gloger's rule — the negative relationship between brightness and humidity -have long been observed but still demand explanation. Finally, the conventional wisdom that tropical birds are more colourful remains largely untested. Location: Australia, New Guinea. Methods: Here, we compared plumage coloration across two families of Australian birds(Meliphagidae, n = 97 species; Acanthizidae, n = 40 species) in a combined spatial and phylogenetic framework. We assessed the extent to which environmental variables extracted from species ranges explain variation in colour traits, while correcting for the autocorrelation inherent in spatially structured data using extensive simulations. Results: We found several strong effects of environment on plumage coloration. Inland species with ranges marked by high aridity and temperature seasonality showed greater colour span among acanthizids, and greater saturation among meliphagids. Gloger's rule was supported in both clades, but more strongly for dorsal plumage. The most consistent correlate in this relationship was vegetation: birds in regions with more vegetation had markedly darker plumage. Ornament hue showed no significant associations with vegetation or climate. Main conclusions: Birds living close to the equator were not more colourful, but species inhabiting arid regions were. Species may respond to the shorter and less predictable breeding seasons of arid environments by evolving increased ornamentation. The consistent relationship we observed between vegetation and dorsal brightness supports a primary role for countershading and background matching in Gloger's rule.

The behaviour of pollinators has important consequences for plant mating. Nectar-feeding birds often display behaviour that results in more pollen carryover than insect pollinators, which is predicted to result in frequent outcrossing and high paternal diversity for bird-pollinated plants. We tested this prediction by quantifying mating system parameters and bird visitation in three populations of an understory bird-pollinated herb, Anigozanthos humilis (Haemodoraceae). Microsatellite markers were used to genotype 131 adult plants, and 211 seeds from 23 maternal plants, from three populations. While outcrossing rates were high, estimates of paternal diversity were surprisingly low compared with other bird-pollinated plants. Despite nectar-feeding birds being common at the study sites, visits to A. humilis flowers were infrequent (62 visits over 21,552 recording hours from motion-triggered cameras, or equivalent to one visit per flower every 10 days), and the majority (76%) were by a single species, the western spinebill Acanthorhynchus superciliosus (Meliphagidae). Pollen counts from 30 captured honeyeaters revealed that A. humilis comprised just 0.3% of the total pollen load. For 10 western spinebills, A. humilis pollen comprised only 4.1% of the pollen load, which equated to an average of 3.9 A. humilis pollen grains per bird. Taken together, our findings suggest that low visitation rates and low pollen loads of floral visitors have led to the low paternal diversity observed in this understory bird-pollinated herb. As such, we shed new light on the conditions that can lead to departures from high paternal diversity for plants competing for the pollination services of generalist nectar-feeding birds.