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Extreme weather events, such as unusually hot or dry conditions, can cause death by exceeding physiological limits, and so cause loss of population. Survival will depend on whether or not susceptible organisms can find refuges that buffer extreme conditions. Microhabitats offer different microclimates to those found within the wider ecosystem, but do these microhabitats effectively buffer extreme climate events relative to the physiological requirements of the animals that frequent them? We collected temperature data from four common microhabitats (soil, tree holes, epiphytes, and vegetation) located from the ground to canopy in primary rainforests in the Philippines. Ambient temperatures were monitored from outside of each microhabitat and from the upper forest canopy, which represent our macrohabitat controls. We measured the critical thermal maxima ( CTmax) of frog and lizard species, which are thermally sensitive and inhabit our microhabitats. Microhabitats reduced mean temperature by 1-2 °C and reduced the duration of extreme temperature exposure by 14-31 times. Microhabitat temperatures were below the CTmax of inhabitant frogs and lizards, whereas macrohabitats consistently contained lethal temperatures. Microhabitat temperatures increased by 0.11-0.66 °C for every 1 °C increase in macrohabitat temperature, and this nonuniformity in temperature change influenced our forecasts of vulnerability for animal communities under climate change. Assuming uniform increases of 6 °C, microhabitats decreased the vulnerability of communities by up to 32-fold, whereas under nonuniform increases of 0.66 to 3.96 °C, microhabitats decreased the vulnerability of communities by up to 108-fold. Microhabitats have extraordinary potential to buffer climate and likely reduce mortality during extreme climate events. These results suggest that predicted changes in distribution due to mortality and habitat shifts that are derived from macroclimatic samples and that assume uniform changes in microclimates relative to macroclimates may be overly pessimistic. Nevertheless, even nonuniform temperature increases within buffered microhabitats would still threaten frogs and lizards. [ABSTRACT FROM AUTHOR]

Long celebrated for its spectacular landscapes and strikingly high levels of endemic biodiversity, the Philippines has been studied intensively by biogeographers for two centuries. Concentration of so many endemic land vertebrates into a small area and shared patterns of distribution in many unrelated forms has inspired a search for common mechanisms of production, partitioning, and maintenance of life in the archipelago. In this review, we ( a) characterize an ongoing renaissance of species discovery, ( b) discuss the changing way biogeographers conceive of the archipelago, ( c) review the role molecular phylogenetic studies play in understanding the evolutionary history of Philippine vertebrates, and ( d) describe how a 25-year Pleistocene island connectivity paradigm continues to provide some explanatory power, but has been augmented by increased understanding of the archipelago's geological history and ecological gradients. Finally, we ( e) review new insights provided by studies of adaptive versus nonadaptive radiation and phylogenetic perspectives on community ecology. [ABSTRACT FROM AUTHOR]

An accurate understanding of species diversity is essential to studies across a wide range of biological subdisciplines. However, delimiting species remains challenging in evolutionary radiations where morphological diversification is rapid and accompanied by little genetic differentiation or when genetic lineage divergence is not accompanied by morphological change. We investigate the utility of a variety of recently developed approaches to examine genetic and morphological diversity, and delimit species in a morphologically conserved group of Southeast Asian lizards. We find that species diversity is vastly underestimated in this unique evolutionary radiation, and find an extreme case where extensive genetic divergence among lineages has been accompanied by little to no differentiation in external morphology. Although we note that different conclusions can be drawn when species are delimited using molecular phylogenetics, coalescent-based methods, or morphological data, it is clear that the use of a pluralistic approach leads to a more comprehensive appraisal of biodiversity, and greater appreciation for processes of diversification in this biologically important geographic region. Similarly, our approach demonstrates how recently developed methodologies can be used to obtain robust estimates of species limits in 'nonadaptive' or 'cryptic' evolutionary radiations. [ABSTRACT FROM AUTHOR]

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Living amphibians exhibit a diversity of ecologies, life histories, and species-rich lineages that offers opportunities for studies of adaptive radiation. We characterize a diverse clade of frogs ( Kaloula, Microhylidae) in the Philippine island archipelago as an example of an adaptive radiation into three primary habitat specialists or ecotypes. We use a novel phylogenetic estimate for this clade to evaluate the tempo of lineage accumulation and morphological diversification. Because species-level phylogenetic estimates for Philippine Kaloula are lacking, we employ dense population sampling to determine the appropriate evolutionary lineages for diversification analyses. We explicitly take phylogenetic uncertainty into account when calculating diversification and disparification statistics and fitting models of diversification. Following dispersal to the Philippines from Southeast Asia, Kaloula radiated rapidly into several well-supported clades. Morphological variation within Kaloula is partly explained by ecotype and accumulated at high levels during this radiation, including within ecotypes. We pinpoint an axis of morphospace related directly to climbing and digging behaviors and find patterns of phenotypic evolution suggestive of ecological opportunity with partitioning into distinct habitat specialists. We conclude by discussing the components of phenotypic diversity that are likely important in amphibian adaptive radiations. [ABSTRACT FROM AUTHOR]

Aim Widespread species found in disturbed habitats are often expected to be human commensals. In island systems, this association predicts that dispersal will be mediated by humans. We investigated the biogeographical relationships among populations of a widespread tree skink that inhabits coastal forest and human-cultivated plantations in Southeast Asia. We sought to determine whether populations of the emerald tree skink, Lamprolepis smaragdina, dispersed via mechanisms that were not human-mediated ('natural' dispersal) or whether dispersal was mediated by humans. The latter scenario predicts low levels of genetic differentiation across a species' range, coupled with a genetic signature of recent range expansion. Location Southeast Asia, the Philippines, Wallacea and the south-western Pacific. Methods We analysed sequences of mitochondrial DNA from 204 samples collected throughout the range of this species. We use phylogenetic and population genetic methods to distinguish between predicted geographical patterns of genetic variation that might indicate natural or human-mediated dispersal. Results In contrast to predictions derived from similar studies of taxonomy and natural history, we found L. smaragdina to be characterized by highly structured and seemingly geographically stable mitochondrial gene lineages. Main conclusions Our results demonstrate a novel pattern of widespread species distribution, never before observed in vertebrates of the Indo-Australian Archipelago. Although this widespread and highly dispersive species is capable of long-distance dispersal, and has a clear history of over-water dispersal, it exhibits sharp genetic differentiation across its range. Our results suggest that random waif dispersal has been a pervasive ongoing phenomenon throughout the evolutionary history of this species. [ABSTRACT FROM AUTHOR]

We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%). The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning). This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study [ABSTRACT FROM AUTHOR]

Aim We examine the genetic diversity within the lizard genus Gekko in the Philippine islands to understand the role of geography and geological history in shaping species diversity in this group. We test multiple biogeographical hypotheses of species relationships, including the recently proposed Palawan Ark Hypothesis. Location Southeast Asia and the Philippines. Methods Samples of all island endemic and widespread Philippine Gekko species were collected and sequenced for one mitochondrial gene (NADH dehydrogenase subunit 2) and one nuclear gene (phosducin). We used maximum likelihood and Bayesian phylogenetic methods to derive the phylogeny. Divergence time analyses were used to estimate the time tree of Philippine Gekko in order to test biogeographical predictions of species relationships. The phylogenetic trees from the posterior distribution of the Bayesian analyses were used for testing biogeographical hypotheses. Haplotype networks were created for the widespread species Gekko mindorensis to explore genetic variation within recently divergent clades. Results Both maximum likelihood and Bayesian phylogenetic analyses indicated that Philippine Gekko species are a diverse clade with a long history in the archipelago. Ancestral range reconstruction and divergence time analyses suggest a Palawan microcontinental origin for this clade, coinciding with Palawan's separation from Asia beginning 30 Ma, with subsequent diversification in the oceanic Philippine islands. The widespread species G. mindorensis and G. monarchus diversified in the late Miocene/early Pliocene and are potentially complexes of numerous undescribed species. Main conclusions The view of the Philippine islands as a 'fringing archipelago' does not explain the pattern of species diversity in the genus Gekko. Philippine Gekko species have diversified within the archipelago over millions of years of isolation, forming a large diverse group of endemic species. Furthermore, the Philippine radiation of gekkonid lizards demonstrates biogeographical patterns most consistent with stochastic colonization followed by in situ diversification. Our results reveal the need to consider deeper time geological processes and their potential role in the evolution of some Philippine terrestrial organisms. [ABSTRACT FROM AUTHOR]

We describe a new species of lizard in the genus Gekko from Sibuyan Island in the Romblon Island group of the central Philippines. Although the new species is diagnosed from other Philippine Gekko by body size and shape, coloration, and multiple characteristics of external morphology, additional support for the recognition of the Sibuyan Gekko population as a distinct evolutionary lineage is garnered from DNA sequence data and biogeographical inference. The new species has been collected on trunks of trees or on granitic rocks along rivers in mature, lowland forest, and on vegetation at forest edges bordering agricultural areas. It is known only from Sibuyan Island and is undoubtedly endemic to this single small, isolated landmass. Although the larger, topographically complex islands of the Philippines have been the targets of numerous recent efforts to estimate vertebrate species diversity, smaller islands of the archipelago have received comparatively less attention and may support significant levels of underappreciated vertebrate diversity. [ABSTRACT FROM AUTHOR]

Garnering support from local people is critical for maintaining ecologically viable and functional protected areas. However, empirical data illustrating local people's awareness of the importance of nature's services is limited; hence possibly impeding effective ecosystem (environmental)-services based conservation efforts. Using data from five protected forests in four developing Southeast Asian countries, we provide evidence that local people living near parks value a wide range of environmental services, including cultural, provisioning, and regulating services, provided by the forests. Local people with longer residency valued environmental services more. Educated as well as poor people valued forest ecosystem services more. Conservation education has some influence on people's environmental awareness. For conservation endeavors to be successful, largescale transmigration programs should be avoided and local people must be provided with alternative sustenance opportunities and basic education in addition to environmental outreach to reduce their reliance on protected forests and to enhance conservation support. [ABSTRACT FROM AUTHOR]

The article focuses on Otosaurus cumingi (Philippine Giant Forest Skink), reporting the discovery of its nest and providing evidence for environmentally cued hatching, as well as data on egg size, clutch size, and hatchling size.

Six alien frogs have been introduced in the Philippines: chronologically, Hylarana erythraea, Rhinella marina, Lithobates catesbeianus, Hoplobatrachus rugulosus, Kaloula pulchra, and Eleutherodactylus planirostris. Here, we collected and synthesized historical and geographical data to reconstruct their history of invasion and to update their current invasion status and distribution in the Philippines. Four pathway categories (falling in 8 subcategories) have facilitated their introduction: (1) intentional 'release' for biological control and hunting in the wild; (2) 'escape' from farms; (3) 'contamination' of agricultural commodities, fish stocks, and ornamental plants/nursery materials; and (4) 'stowaway' on container/bulk and (hitchhiker on) ship/boat – of which the last two were important in most recent introductions. Their spatio-temporal pattern of distribution showed a stratified-diffusion process of spread involving primarily leading-edge and long-distance dispersal. The pathways that facilitated their secondary (post-introduction) long-distance dispersal were either the same as those of their introduction or shifted over time. Estimation of rate of spread showed that H. erythraea, R. marina, H. rugulosus, and K. pulchra have not reached spatial saturation and are conditioning to spread, with the latter spreading fastest. The status of Lithobates catesbeianus, whether it successfully established or not, is undetermined. Meanwhile, the other alien frogs are now considered fully invasive species, of which R. marina is the most widespread, whereas E. planirostris is the least distributed. Our study provides science-based information that can help guide the development and implementation of pathway-specific measures to prevent and control future and current invasions by alien frogs. [ABSTRACT FROM AUTHOR]

The authors express their views on the conservation crisis facing Southeast Asian amphibians. They highlight the need for the identification and strict protection of habitat considered as having high amphibian species diversity as the most critical conservation action required. They propose long-term population monitoring, enhanced survey efforts, collection of basic biological and ecological information, continued taxonomic research and evaluation of the impact of commercial trade for food, medicine and pets.

Angel Chua Alcala, a pioneer in community-led marine resource management and a renowned Filipino herpetologist, passed away. Born in 1929 in the Philippines, Alcala developed a deep connection with nature and studied biology, specializing in amphibians and reptiles. He made significant contributions to the study of Philippine amphibians and reptiles, describing over 50 new species. Alcala also played a crucial role in the development of community-led marine resource management, establishing the first Marine Protected Area in 1973. His work has had a lasting impact on the conservation of coral reefs and marine biodiversity in the Philippines, serving as a model for other countries. Alcala's research demonstrated the effectiveness of Marine Protected Areas in restoring biodiversity and enhancing fisheries. He also held government positions, implementing policies to protect the environment while considering the welfare of indigenous people. Alcala's contributions to marine conservation and mentorship of young scientists are widely recognized and appreciated. [Extracted from the article]

The Philippine-endemic elapid genus Hemibungarus consists of three described species that are widely distributed across northern and central portions of the archipelago. Hemibungarus calligaster, H. mcclungi, and H. gemianulis were originally diagnosed, and remain recognized today, primarily based on differences in color pattern. Previous studies and faunal checklists suggest that these species occupy distinct geographic distributions within the Philippines. However, the relatively low numbers of specimens in collections and the misidentification of older specimens under outdated taxonomy have hampered a synthetic understanding of their actual distributional limits. Thus, an in-depth revisiting of the range of external morphological and color pattern variation within and among each species is still needed to clarify species boundaries and determine whether distributional limits change once properly documented. We provide a geographic assessment of morphological variation, using 98 specimens of Hemibungarus from institutional collections and public databases to reevaluate the range of phenotypic variation exhibited by each taxon and critically assess the geographic ranges of all three species of Hemibungarus. We use these data and multivariate statistics (principal coordinate and linear discriminant analyses) to demonstrate quantitatively how meristic data support the phenotypic distinctiveness of each species and to update the identifications of all accessible specimens. Georeferencing all specimens reidentified with morphological data indicates that H. calligaster is limited to central and northern regions of Luzon Island, whereas H. gemianulis is restricted to islands in central Philippines (Visayas). Hemibungarus mcclungi, previously considered restricted to the Bicol Peninsula in southern Luzon, appears to be more widely distributed--extending north into central and northern Luzon. We also identify a population of Hemibungarus that is intermediate in morphology between the parapatric H. calligaster and H. mcclungi, which raises the question of species boundaries and should be the focus of future study. Overall, our results provide a much-needed reconsideration of the identities of all available specimens in the world's biodiversity repositories, which use newly summarized data to elucidate the geographic distributions of the members of this enigmatic elapid genus, identify future directions for research on this group, and highlight the importance of returning to verified species occurrence data from the source (museum specimens) when considering biogeographical questions, species boundaries, and all related natural history studies. [ABSTRACT FROM AUTHOR]

Niche shifts and environmental non-equilibrium in invading alien species undermine niche-based predictions of alien species' potential distributions and, consequently, their usefulness for invasion risk assessments. Here, we compared the realized climatic niches of four alien amphibian species (Hylarana erythraea, Rhinella marina, Hoplobatrachus rugulosus, and Kaloula pulchra) in their native and Philippine-invaded ranges to investigate niche changes that have unfolded during their invasion and, with this, assessed the extent of niche conservatism and environmental equilibrium. We investigated how niche changes affected reciprocal transferability of ecological niche models (ENMs) calibrated using data from the species' native and Philippine-invaded ranges, and both ranges combined. We found varying levels of niche change across the species' realized climatic niches in the Philippines: climatic niche shift for H. rugulosus; niche conservatism for R. marina and K. pulchra; environmental non-equilibrium in the Philippine-invaded range for all species; and environmental non-equilibrium in the native range or adaptive changes post-introduction for all species except H. erythraea. Niche changes undermined the reciprocal transferability of ENMs calibrated using native and Philippine-invaded range data. Our paper highlights the difficulty of predicting potential distributions given niche shifts and environmental non-equilibrium; we suggest calibrating ENMs with data from species' combined native and invaded ranges, and to regularly reassess niche changes and recalibrate ENMs as species' invasions progress. [ABSTRACT FROM AUTHOR]

Once distributed all over the Philippines, the endemic Philippine Crocodile (Crocodylus mindorensis) is nowadays threatened with extinction. It is estimated that less than 140 mature individuals live in the wild. Human activities like fishing and poaching, as well as land-use change and habitat conversion cause a continuing threat to the remaining populations. Therefore, designated protected areas (PAs) were evaluated with species distribution models (SDMs) and also to see if most suitable areas are covered by PAs in order to improve future conservation efforts. For this purpose, the existing IUCN-reserves were analysed for potential habitat suitability (combining bioclimatic and remote sensing variables), wetland occurrences and the human footprint index by using MaxEnt and QGIS. Based on species records, our final SDM showed high performance and revealed the climatically most suitable areas for the species, which were mostly on Luzon and Mindanao. However, only small parts of the climatically suitable wetlands are currently covered by reserves (0.3-46.3%). In addition, none of the species' records was located within a PA. The anthropogenic pressures in the reserves measured by human footprint index (considering eight variables i.e. 'population density', 'navigable waterways', 'crop lands' and 'roads') were diverse and varied between a low and moderate level. Most of the records were found in areas with a moderate human footprint. Considering the three criteria, 'Lake Lanao Watershed Reservation', 'Angat Watershed Forest Reserve District (Metro Water District)', 'Northern Sierra Madre Natural Park', 'Talaytay Protected Landscape' and 'Agusan Marsh Wildlife Sanctuary' revealed to be the most suitable conservation areas for C. mindorensis, whereas suitable areas outside PAs are highly recommended for further surveys. We recommend to declare Ligawasan Marsh, Mindanao as a PA as this area harbours a large population of C. mindorensis. The declaration of more climatically suitable areas with low level of human footprint to PAs is a necessary step for the long-term conservation of this endemic crocodile species. The current network of existing PAs needs improvement in order to provide well-suited and long-term protection for C. mindorensis. More surveys are also necessary to find hidden, so far overlooked populations and to assess C. mindorensis tolerance level for human impacts. [ABSTRACT FROM AUTHOR]

Species diversity in skinks in the genus Brachymeles recently has undergone a state of flux, with numerous taxonomic discoveries over the past flow years. Newly available, robust data sets from morphological data and molecular sequences have revealed that taxonomic diversity within this unique group of lizards is substantially underestimated. In this third recent monographic revision of a major Brachymeles clade, we review the medium-sized, pentadactyl species of the Brachymeles gracilis Complex (now known to include B. pathfinderi) and describe three new species in this unique clade of endemic Philippine lizards. For more than three decades B. gracilis has been recognized as a single polytypic, "widespread" species. The species' wide geographic range has persisted as a result of weak sampling, morphologically similar body sizes, scale pigmentation, and patterns of sealation among populations. However, previous authors have noted morphological variation between populations on different islands, as well as in geographically different subregions across the large southern island of Mindanao in the Philippines. Our new data build on these observations and extend them to inference of species boundaries. We evaluate both morphological and genetic data to define species limits in B. gracilis and its close relatives, and our data indicate that the "widespread" species B. gracilis is actually a complex of at least six distinct lineages. In order to clarify the status ofB. suluensis (a species collected only once, in 1918) we redescribe this enigmatic taxon. Phylogenetic analyses of available B. gracilis sampling reveal that some of these lineages are not each others' closest relatives, but are all genetically distinct. All but two of the taxa we define possess allopatric geographic ranges and differ from their congeners by numerous diagnostic characters of external morphology, and therefore should be recognized as full species in accordance with any lineage-based species concept. Over the past 3 yr, the species diversity of the genus Brachymeles has increased by 125%. [ABSTRACT FROM AUTHOR]

The Philippine archipelago harbours a remarkable diversity of harvestmen, with respect to both taxonomy and complexity of biogeographic origins. Among the armoured harvestmen (suborder Laniatores), six families of distantly related groups occur in this archipelago. Here, we describe a new species of the family Tithaeidae, Tithaeus odysseus sp. nov., discovered during a collecting campaign on the island of Mindanao. The description of this species expands the known distribution of the family and demonstrates another exception to the zoogeographic boundary known as Huxley's Line which putatively separates the biota of the Philippines (excluding the Palawan island group) from the Sunda Shelf biota. Given the coincident distributions of Tithaeidae and the mite harvestman family Stylocellidae (Cyphophthalmi), a group renowned for its poor dispersal ability, we inferred phylogenetic relationships and divergence times of the Philippines lineages of both families by using a comprehensive molecular dating analysis of all Opiliones. The internal phylogeny of Tithaeidae mirrored the biogeography of Philippine Stylocellidae, showing a close affinity between the Philippine and Bornean species. Molecular dating showed contemporaneous colonisation of Mindanao by both families in the Cretaceous. We infer these patterns to reflect faunal connections between the southern Philippines and Borneo via the Zamboanga Peninsula. To render the genus Tithaeus monophyletic, we synonymise Metatithaeus with Tithaeus (new synonymy). We describe a new species of the family Tithaeidae, Tithaeus odysseus sp. nov., discovered during a collecting campaign on the island of Mindanao. The description of this species expands the known distribution of the family and demonstrates another exception to the faunal break called Huxley's Line (separating the Philippine biota from the Sunda Shelf). Molecular dating showed contemporaneous colonisation of Mindanao by the distantly related families Tithaeidae and Stylocellidae in the Cretaceous, likely via the Zamboanga Peninsula. [ABSTRACT FROM AUTHOR]

Biodiversity is spatially organized by climatic gradients across elevation and latitude. But do other gradients exist that might drive biogeographic patterns? Here, we show that rainforest's vertical strata provide climatic gradients much steeper than those offered by elevation and latitude, and biodiversity of arboreal species is organized along this gradient. In Philippine and Singaporean rainforests, we demonstrate that rainforest frogs tend to shift up in the rainforest strata as altitude increases. Moreover, a Philippine-wide dataset of frog distributions shows that frog assemblages become increasingly arboreal at higher elevations. Thus, increased arboreality with elevation at broad biogeographic scales mirrors patterns we observed at local scales. Our proposed ‘arboreality hypothesis' suggests that the ability to exploit arboreal habitats confers the potential for larger geographical distributions because species can shift their location in the rainforest strata to compensate for shifts in temperature associated with elevation and latitude. This novel finding may help explain patterns of species richness and abundance wherever vegetation produces a vertical microclimatic gradient. Our results further suggest that global warming will ‘flatten' the biodiversity in rainforests by pushing arboreal species towards the cooler and wetter ground. This ‘flattening' could potentially have serious impacts on forest functioning and species survival. [ABSTRACT FROM AUTHOR]

The negative ecological impacts of invasive species are well documented, although their effects are often more pronounced on islands than on the mainland. This is because many island species exhibit high degrees of endemism, have small geographic distributions, are rare, and exhibit low genetic diversity, which reduces their ability to respond to new emerging threats. One of the world's most notorious invasive species is the cane toad (Rhinella marina), which is a voracious predator that is native to the neo-tropics but was intentionally introduced in the early 20th century to many warm regions and islands to control crop pests. Cane toads produce two kinds of toxins in neck glands that are often lethal to nonadapted predators in the invasive range. Although well-studied in Australia, their ecological impacts on many islands have received much less attention. Australia is the sixth largest country on Earth, so the effects of cane toads on small island nations may differ considerably from there. Here, we discuss the potential ecological impacts of cane toads in the Philippines and on other island nations. Cane toads were introduced onto the largest Philippine island, Luzon, in 1930 and have since spread over all but a few of the 7641 islands that make up the country. We speculate that, unlike most biological invasions with predators or herbivores where the ecological effects are strictly 'top-down', cane toads, by virtue of their biology and ecology, may have even more serious effects on island fauna because they exhibit both 'top-down' and 'bottom-up' effects. [ABSTRACT FROM AUTHOR]

Convergence in communication appears rare compared with other forms of adaptation. This is puzzling, given communication is acutely dependent on the environment and expected to converge in form when animals communicate in similar habitats. We uncover deep‐time convergence in territorial communication between two groups of tropical lizards separated by over 140 million years of evolution: the Southeast Asian Draco and Caribbean Anolis. These groups have repeatedly converged in multiple aspects of display along common environmental gradients. Robot playbacks to free‐ranging lizards confirmed that the most prominent convergence in display is adaptive, as it improves signal detection. We then provide evidence from a sample of the literature to further show that convergent adaptation among highly divergent animal groups is almost certainly widespread in nature. Signal evolution is therefore curbed towards the same set of adaptive solutions, especially when animals are challenged with the problem of communicating effectively in noisy environments. [ABSTRACT FROM AUTHOR]

We performed the first host-parasite survey of the Philippine crocodile, Crocodylus mindorensis , a critically endangered species for which ecological information is lacking. We collected by gastric lavage samples of the stomach contents of crocodiles (n = 10) residing at the Palawan Wildlife Rescue and Conservation Center in Puerto Princesa, Palawan, Philippines. The only parasite detected was an acanthocephalan, which was identified as Neorhadinorhynchus nudus (n = 68), a parasite typically found in the marine fish species consumed by three crocodile individuals. Given the known hosts of N. nudus , its parasitism of C. mindorensis in captivity is likely established by consumption of marine fish. Our findings have implications for the conservation management of C. mindorensis , particularly in terms of preventing introduction of parasites that could lead to development of infectious disease or alter the fitness of captive animals. Unlabelled Image • The first to record parasite of the gastrointestinal tract of Philippine crocodile • Three Crocodylus mindorensis were parasitized by one species of acanthocephalan • The parasite was identified as Neorhadinorhynchus nudus , a parasite of marine fish [ABSTRACT FROM AUTHOR]

We identified hypotheses for the cause and consequences of the loss of complexity in animal signals and tested these using a genus of visually communicating lizards, the Southeast Asian Draco lizards. Males of some species have lost the headbob component from their display, which is otherwise central to the communication of this genus. These males instead display a large, colorful dewlap to defend territories and attract mates. This dewlap initially evolved to augment the headbob component of the display, but has become the exclusive system of communication. We tested whether the loss of headbobs was caused by relaxed selection, habitat-dependent constraints, or size-specific energetic constraints on display movement. We then examined whether the consequences of this loss have been mitigated by increased signaling effort or complexity in the color of the dewlap. It appears the increased cost of display movement resulting from the evolution of large body size might have contributed to the loss of headbobs and has been somewhat compensated for by the evolution of greater complexity in dewlap color. However, this evolutionary shift is unlikely to have maintained the complexity previously present in the communication system, resulting in an apparent detrimental loss of information potential., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE). All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Biodiversity is spatially organized by climatic gradients across elevation and latitude. But do other gradients exist that might drive biogeographic patterns? Here, we show that rainforest's vertical strata provide climatic gradients much steeper than those offered by elevation and latitude, and biodiversity of arboreal species is organized along this gradient. In Philippine and Singaporean rainforests, we demonstrate that rainforest frogs tend to shift up in the rainforest strata as altitude increases. Moreover, a Philippine-wide dataset of frog distributions shows that frog assemblages become increasingly arboreal at higher elevations. Thus, increased arboreality with elevation at broad biogeographic scales mirrors patterns we observed at local scales. Our proposed 'arboreality hypothesis' suggests that the ability to exploit arboreal habitats confers the potential for larger geographical distributions because species can shift their location in the rainforest strata to compensate for shifts in temperature associated with elevation and latitude. This novel finding may help explain patterns of species richness and abundance wherever vegetation produces a vertical microclimatic gradient. Our results further suggest that global warming will 'flatten' the biodiversity in rainforests by pushing arboreal species towards the cooler and wetter ground. This 'flattening' could potentially have serious impacts on forest functioning and species survival.

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses. As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world’s major tropical regions. Our analysis reveals great variation in reserve ‘health’: about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.