Search

ABSTRACT Quadrupedal animals traveling on arboreal supports change aspects of locomotion to avoid slipping and falls. This study compares locomotor biomechanics in two small mammals: first, the gray short‐tailed opossum (Monodelphis domestica) predominantly trots, which is a symmetrical gait. The second species, the Siberian chipmunk (Tamias sibiricus), primarily bounds or half‐bounds. Trotting and bounding differ fundamentally in three aspects: location and timing of hand and foot placement; in the way that the trunk bends (trotting, mediolateral bending; bounding, flexion, and extension); and in the dynamics of the center of mass. Both species ran on a flat track and a 2 cm diameter cylindrical track, instrumented with a force plate or pole. For bounding chipmunks, the force pole was modified to measure force only on the right side. We measured speed, duty factor, and force, and calculated vertical, braking, propulsive, and net mediolateral impulses. Vertical and fore‐aft impulses were different between trotting opossums and bounding chipmunks, but between trackway types, these impulses were similar within each species. The modifications used by each species to travel on arboreal supports were similar, except in one important respect. Net mediolateral impulse in opossums changed from laterally directed on the flat trackway to medial on the arboreal. But in chipmunks, these impulses on the flat track were medially‐directed, and on the arboreal track, the amount of variability was substantially greater. We conclude that chipmunks—and perhaps any bounding animal—are less consistent from stride to stride in their locomotion. This inconsistency requires constant medial and lateral impulses to correct their trajectory when traveling on arboreal surfaces. [ABSTRACT FROM AUTHOR]

As an arboreal animal, tree frogs face diverse challenges when landing on perches, including variations in substrate shape, diameter, flexibility, and angular distribution, with potentially significant consequences for failed landings. Research on tree frog landing behavior on perches, especially concerning landing on vertical substrates, remains limited. This study investigated the landing strategies (forelimb, abdomen, and hindlimb) of tree frogs on vertical perches, considering perch diameter. Although all three strategies were observed across perches of different diameters, their frequencies differed. Forelimb landing was most common across all perch diameters, with its frequency increasing with perch diameter, while abdomen and hindlimb landing strategies were more prevalent on smaller diameter perches. During the process from take‐off to landing, the body axis underwent some deviation owing to the asymmetric movement of the left and right limbs; however, these deviations did not significantly differ among landing strategies. Additionally, different landing strategies led to variations in the landing forces, with abdominal landings generating significantly higher impact forces than the other two strategies. These findings provide insights into the biomechanics and biological adaptations of tree frogs when landing on challenging substrates, such as leaves or branches. [ABSTRACT FROM AUTHOR]

Understanding the locomotor characteristics of early diverging ground‐walking chameleons (members of the genera Brookesia, Rhampholeon, Palleon, and Rieppeleon) can help to explain how their unique morphology is adapted to fit their environment and mode of life. However, nearly all quantitative studies of chameleon locomotion thus far have focused on the larger "true arboreal" chameleons. We investigated kinematics and spatiotemporal gait characteristics of the Brown Leaf Chameleon (Brookesia superciliaris) on different substrates and compared them with true arboreal chameleons, nonchameleon lizards, and other small arboreal animals. Brookesia exhibits a combination of locomotor traits, some of which are traditionally arboreal, others more terrestrial, and a few that are very unusual. Like other chameleons, Brookesia moved more slowly on narrow dowels than on broad planks (simulating arboreal and terrestrial substrates, respectively), and its speed was primarily regulated by stride frequency rather than stride length. While Brookesia exhibits the traditionally arboreal trait of a high degree of humeral protraction at the beginning of stance, unlike most arboreal tetrapods, it uses smaller shoulder and hip excursions on narrower substrates, possibly reflecting its more terrestrial habits. When moving at very slow speeds, Brookesia often adopts an unusual footfall pattern, lateral‐sequence lateral‐couplets. Because Brookesia is a member of one of the earliest‐diverging groups of chameleons, its locomotion may provide a good model for an intermediate stage in the evolution of arboreal chameleons. Thus, the transition to a fully arboreal way of life in "true arboreal" chameleons may have involved changes in spatiotemporal and kinematic characteristics as well as morphology. [ABSTRACT FROM AUTHOR]

Summary: Roads and other linear infrastructure create treeless gaps that can limit the movement of non‐flying, arboreal animals. These negative effects are particularly strong in dense forests, where even narrow infrastructure corridors represent a significant change in habitat structure. Artificial canopy bridges are an increasingly common approach to mitigating the barrier effect of roads and other linear infrastructure on the movement of arboreal mammals; however, questions remain about the success of various designs for different species. Here we conduct an experimental evaluation of the response of a critically endangered possum, Leadbeater's Possum (Gymnobelideus leadbeateri), to two artificial canopy bridge designs: single‐rope bridges and ladder bridges. We found that both bridges were used by Leadbeater's Possum and five other species of arboreal marsupial to cross narrow, forestry roads. However, Leadbeater's Possums crossed ladder bridges 13 times more often than the single‐rope design (average of 564.5 and 41.75 crossings per design respectively). Radiotelemetry conducted on four Leadbeater's Possums prior to bridge installation detected no road crossings, providing preliminary evidence that the bridges improved cross‐road movement. Ladder bridges appear to be the better design choice for a wider range of arboreal marsupials as they were used more frequently, offer greater stability, and provide better predator avoidance than single‐rope designs. [ABSTRACT FROM AUTHOR]

Arboreal environments require overcoming navigational challenges not typically encountered in other terrestrial habitats. Supports are unevenly distributed and vary in diameter, orientation, and compliance. To better understand the strategies that arboreal animals use to maintain stability in this environment, laboratory researchers must endeavor to mimic those conditions. Here, we evaluate how squirrel monkeys (Saimiri boliviensis) adjust their locomotor mechanics in response to variation in support diameter and compliance. We used high‐speed cameras to film two juvenile female monkeys as they walked across poles of varying diameters (5, 2.5, and 1.25 cm). Poles were mounted on either a stiff wooden base ("stable" condition) or foam blocks ("compliant" condition). Six force transducers embedded within the pole trackway recorded substrate reaction forces during locomotion. We predicted that squirrel monkeys would walk more slowly on narrow and compliant supports and adopt more "compliant" gait mechanics, increasing stride lengths, duty factors, and an average number of limbs gripping the support, while the decreasing center of mass height, stride frequencies, and peak forces. We observed few significant adjustments to squirrel monkey locomotor kinematics in response to changes in either support diameter or compliance, and the changes we did observe were often tempered by interactions with locomotor speed. These results differ from a similar study of common marmosets (i.e., Callithrix jacchus, with relatively poor grasping abilities), where variation in diameter and compliance substantially impacted gait kinematics. Squirrel monkeys' strong grasping apparatus, long and mobile tails, and other adaptations for arboreal travel likely facilitate robust locomotor performance despite substrate precarity. Highlights: Squirrel monkeys make few gait changes on supports that are narrower and more compliant.Grasping extremities, long tails, and other adaptations for arboreal travel permit high locomotor performance in the face of increasing substrate precarity. [ABSTRACT FROM AUTHOR]

The ability to safely ascend and descend is critical to the success of arboreal animals. Nonprimate mammals typically descend supports headfirst aided by their claws, but primates must rely on grasping, and use a variety of behaviors to move down within an arboreal environment, including headfirst and tailfirst descending. This study assesses hypothesized body mass limits on vertical headfirst descent and identifies approximate support orientations and diameters at which headfirst descent is ceased in a sample of nine strepsirrhines species ranging in mass from 0.06 to 4.5 kg. Species under 1 kg, arboreal quadrupeds Cheirogaleus medius and Microcebus murinus, and slow climber Nycticebus pygmaeus, always descended supports headfirst regardless of orientation and diameter as long as a grasp could be established. Arboreal quadrupedal species above 1 kg, Daubetonia madagascariensis, Eulemur coronatus, Eulemur mongoz, Lemur catta, and Varecia variegata differed in the orientation at which they ceased using headfirst descent and the types of alternative descending behaviors they employed. Lemur catta, a highly terrestrial species, started to employ tailfirst descents at 45° and completely stopped using headfirst descent on steeper and thicker supports. Other arboreal quadrupeds, D. madagascariensis, E. coronatus, E. mongoz, and V. variegata, began using tailfirst descent at 60°. The vertical clinging and leaping species Propithecus coquereli rarely engaged in above branch quadrupedalism, and individuals were observed using tailfirst descents on supports as shallow as 15°. This study shows the ways in which mass and anatomy may constrain use of headfirst descent through arboreal environments, and the alternate strategies strepsirrhine primates employ to descend. RESEARCH HIGHLIGHTS: Primates under 1 kg performed headfirst descent on all support orientations and never performed tailfirst descentPrimates larger than 1 kg stopped using headfirst descent at different support orientations between species, with some variation potentially explained by anatomical features such as intermembral index and digit length. [ABSTRACT FROM AUTHOR]

Keywords: Amazonia; home range; jaguar; movement ecology; Panthera onca; varzea floodplain forest EN Amazonia home range jaguar movement ecology Panthera onca varzea floodplain forest 1 4 4 05/05/21 20210501 NES 210501 Large felids (>30 kg) have exclusively carnivorous diets and depend upon medium and large terrestrial prey to fuel high metabolic demands (Sunquist and Sunquist 2002, Carbone et al. 2007). Our findings also raise questions regarding the potential conservation implications of varzea environments for sustaining jaguar populations in the Amazon basin and how anthropogenic or climate-mediated changes may influence the annual flood regime that fuels these systems, affecting jaguar populations directly. Amazonia, home range, jaguar, movement ecology, Panthera onca, varzea floodplain forest Jaguar (Panthera onca) population dynamics, feeding ecology, human induced mortality, and conservation in the Várzea Floodplain Forests of Amazonia. [Extracted from the article]

Arboreal mammals have evolved a range of biomechanical adaptations that allow them to navigate trees effectively. One such feature that has received considerable attention is the importance of vision that helps arboreal animals assess gap distances, assure proper foot placement, and inspect potential risks. While there is considerable debate about the relative importance of the visual system specifics, there is little doubt that the ability to at least see the environment must confer some level of safety when navigating arboreal substrates. In this study, we explore spatiotemporal and kinematic patterns of arboreal locomotion in the Vietnamese pygmy dormouse (Typhlomys chapensis), a blind rodent that uses ultrasonic echolocation to navigate in tree canopies. We compare these data with five other species of arboreal rodents and primates. Spatiotemporal gait characteristics are largely similar between the Vietnamese pygmy dormouse and other small‐bodied arboreal species analyzed. Most notable is the tendency for relatively high‐speed asymmetrical gaits on large‐diameter substrates and slower symmetrical lateral‐sequence gaits on small‐diameter substrates. Furthermore, for all species speed is primarily regulated by increasing stride frequency rather than length. Kinematics of the Vietnamese pygmy dormouse changed little in response substrate size and were primarily driven by speed. These findings suggest that the information gathered during ultrasonic scanning is sufficient to allow effective quadrupedal locomotion while moving on arboreal supports. The Vietnamese pygmy dormouse may serve as a model for the quadrupedal nocturnal ancestor of bats, which had started developing ultrasonic echolocation and reducing vision while likely occupying an arboreal niche. Research Highlights: Spatiotemporal gait characteristics are largely similar between the Vietnamese pygmy dormouse, a blind echolocating rodent, and other small‐bodied arboreal species. These data can be used to infer the locomotor behavior of proto‐bats. [ABSTRACT FROM AUTHOR]

Objectives: The guenons (tribe Cercopithecini) are a diverse and primarily arboreal radiation of Old World monkeys from Africa. However, preliminary behavioral observations of the lesula (Cercopithecus lomamiensis), a little‐known guenon species described in 2012, report it spending substantial amounts of time on the ground. New specimens allow us to present the first description of lesula postcranial morphology and apply a comparative functional morphology approach to supplement our knowledge of its locomotor behavior. Materials and methods: To infer the substrate use preferences of the lesula, 22 postcranial variables correlated with locomotion were assessed in a sample of 151 adult guenon specimens, including two C. lomamiensis. Using multivariate statistical analyses, we predict the amount of time the lesula spends on the ground relative to the comparative sample. Results: Results suggest that the lesula spends nearly half its time on the ground, and the two available individuals were classified as semiterrestrial and terrestrial with strong support. Comparisons with two outgroup cercopithecid taxa (Colobus guereza and Macaca mulatta) demonstrate that, as a group, guenons retain signals of a generalized, semiterrestrially adapted postcranium compared to specialized arboreal cercopithecids. Discussion: These results corroborate preliminary behavioral observations of the lesula as a semiterrestrial to terrestrial primate and imply multiple evolutionary transitions in substrate use among the guenon radiation. A broader view of cercopithecoid evolution suggests that a semiterrestrial ancestor for extant guenons is more parsimonious than an arboreal one, indicating that the arboreal members of the group are probably recently derived from a more semiterrestrial ancestor. [ABSTRACT FROM AUTHOR]

Locomotor diversity has meant many different things depending on the subject area or investigator. While no concrete definition of locomotor diversity is currently available, this has not stopped researchers from making a number of assertions about the underlying mechanisms that determine whether a species will have high or low locomotor diversity. Some of these claims include that: (1) arboreal primates demonstrate higher locomotor diversity than terrestrial species; (2) anatomically generalized and small‐bodied primates demonstrate higher locomotor diversity than anatomically specialized and large‐bodied taxa; and (3) primates demonstrate higher locomotor diversity compared to non‐primate mammals. None of these claims have been tested in any sort of comparative framework. Using previously published locomotor repertoire data from 110 mammalian species, this study co‐opted the Shannon–Wiener diversity index to calculate a singular measure of locomotor diversity. Phylogenetic analyses of these locomotor diversity indices reveal that within primates, small‐bodied species demonstrate greater locomotor diversity than large‐bodied taxa. However, this effect becomes non‐significant when accounting for differences in substrate‐use (i.e. arboreal vs. terrestrial). Anatomical specialization has no effect on locomotor diversity in primates. Furthermore, primates do not inherently have greater locomotor diversity than other mammalian taxa. Findings from this study suggest that movement on arboreal substrates requires all mammals, regardless of taxonomic affiliation, to demonstrate high locomotor diversity. These data further highlight the challenges faced by arboreal animals and raise the possibility that being able to switch fluidly and frequently between many different locomotor modes may be advantageous for animals moving in an arboreal milieu. Locomotor diversity has meant many different things depending on the subject area or investigator, but there is no concrete definition of locomotor diversity currently available. Using previously published locomotor repertoire data from 110 mammalian species, this study co‐opted the Shannon–Wiener diversity index to calculate a singular measure of locomotor diversity. Phylogenetic analyses of these locomotor diversity indices reveal that within primates, small‐bodied species demonstrate greater locomotor diversity than large‐bodied taxa. Furthermore, primates do not inherently have greater locomotor diversity than other mammalian taxa. Findings from this study suggest that movement on arboreal substrates requires all mammals, regardless of taxonomic affiliation, to demonstrate high locomotor diversity. These data further highlight the challenges faced by arboreal animals and raise the possibility that being able to switch fluidly and frequently between many different locomotor modes may be advantageous for animals moving in an arboreal milieu. [ABSTRACT FROM AUTHOR]

Summary: Nest boxes are commonly installed to support hollow‐using species where the abundance of hollow‐bearing trees is deficient. Recent studies have provided equivocal evidence about the effectiveness of nest box projects and have highlighted significant management costs associated with some projects. We document the functionality of 303 nest boxes installed across five different community‐led projects in southern Australia for periods of 10–25 years. As expected, we found that nest boxes lost functionality over time. However, 60% remained functional to support the Brush‐tailed Phascogale (Phascogale tapoatafa) and the Sugar Glider (Petaurus breviceps) after almost 20 years. Years installed, method of nest box attachment and tree species influenced whether boxes remained functional. Nest box construction material changed over time so could not be assessed specifically. When inspected in a single year, the Brush‐tailed Phascogale occupied 9% of functional boxes and another 48% contained their nests. The Sugar Glider occupied 15% of functional boxes and another 22% contained their nests. These values suggest the nest box installations were highly effective for these species, although more detailed study is needed to understand what contribution these installations have made to support the local populations. Maintenance of most nest boxes occurred twice a year in the first five years after installation, but many received no maintenance for periods of three years, and some 10–15 years, before our census. Our findings suggest that infrequent maintenance by community groups can sustain nest box projects over periods of several decades. Research into employing nest boxes as a management tool in Australia is still in its infancy. Further studies are needed to resolve factors that limit their effectiveness. [ABSTRACT FROM AUTHOR]

Abstract: Despite years of study, it remains unclear if and to what extent the effects of extra‐floral nectaries (EFNs) on arboreal ants observed on individual trees scale up to larger spatial scales. Here, we address this issue in Brazilian savanna and tested three predictions: (i) Trees with EFN have higher richness of arboreal ant species than trees without; (ii) Arboreal ant species richness increases with the proportion of total EFN‐bearing trees at the site scale, due to a higher occurrence of non‐core ant species; (iii) Ant species composition changes with the proportion of EFN‐bearing trees at the site scale. We sampled arboreal ants in 32 plots with EFN‐bearing trees ranging from 0% to 60% of all trees. We sampled 72 ant species, from which 17 (mostly belonging to Camponotus, Cephalotes and Crematogaster) were identified as core species in at least one of the ant‐EFN networks in the 32 plots. Ant species richness was significantly higher on EFN‐bearing trees. We identified 11 ant species that preferentially occurred on EFN‐bearing trees, all of which were core partners in networks. Species richness at the site scales increased with the proportion of EFN‐bearing trees, regardless of tree density and richness; this pattern was due to a higher occurrence of non‐core ant species. Finally, species composition also varied with the proportion of EFN‐bearing trees. Therefore, we found that the presence of EFNs not only influences arboreal ants on individual trees but also has a substantial effect on the ant‐EFN network on a broader community scale. The increase in non‐core species site scale reveals that this interaction is unlikely to result in substantially enhanced protection services for EFN‐bearing plants. [ABSTRACT FROM AUTHOR]

Abstract: Domestic livestock grazing directly alters ground‐level habitat but its effects on arboreal habitat are poorly known. Similarly, the response to grazing of ground‐dwelling fauna has been examined, but there are few studies of arboreal fauna. Globally, grazing has been implicated in the decline of vertebrate fauna species, but some species appear resistant to the effects of grazing, either benefiting from the structural changes at ground level or avoiding them, as may be the case with arboreal species. Here, we examine arboreal and terrestrial habitat responses and reptile community responses to grazing, to determine whether arboreal reptile species are more resistant than terrestrial reptile species. We conducted arboreal and terrestrial reptile surveys on four different grazing treatments, at a 19‐year experimental grazing trial in northern Australia. To compare the grazing response of arboreal and terrestrial reptile assemblages, we used community, functional group and individual species‐level analyses. Species responses were modelled in relation to landscape‐scale and microhabitat variables. Arboreal reptile species were resistant to the impact of grazing, whereas terrestrial reptiles were negatively affected by heavy grazing. Terrestrial reptiles were positively associated with complex ground structures, which were greatly reduced in heavily grazed areas. Arboreal lizards responded positively to microhabitat features such as tree hollows. Synthesis and applications. Arboreal and terrestrial reptiles have different responses to the impact of livestock grazing. This has implications for rangeland management, particularly if management objectives include goals relating to conserving certain species or functional groups. Arboreal reptiles showed resistance in a landscape that is grazed, but where trees have not been cleared. We highlight the importance of retaining trees in rangelands for both terrestrial and arboreal microhabitats. [ABSTRACT FROM AUTHOR]

Aim To evaluate the extent to which ant species richness in Neotropical savannas varies with macrogeographic variables, and to identify the potential climatic drivers of such variation. Location The Cerrado savanna biome of central Brazil, in a region spanning ca. 20° of latitude and 18°of longitude. Methods Standardized sampling of the arboreal and ground-dwelling faunas was performed in 29 well-preserved savanna sites using pitfall traps. Species were classified according to their habitat affinities: open-savanna specialists, forest-associated species or habitat generalists. We used generalized linear models to evaluate the importance of geographic (latitude, longitude and elevation) and climatic (mean temperature and three metrics of rainfall) variables as predictors of species richness. Results The total number of species recorded at each site varied more than twofold (from 59 to 144), and latitude was the best geographic correlate of overall species richness. However, contrary to the expected pattern, more species were found at higher than lower latitudes. This reversed latitudinal pattern of diversity occurred for both the arboreal and ground-dwelling faunas, and for the habitat generalists and forest specialists. The savanna specialists showed a mid-latitudinal peak in diversity. Overall, there was a significant positive association between rainfall and species richness, but the strength of this relationship varied with ant habitat affinity. Main conclusions The Cerrado ant fauna shows a reverse latitudinal gradient in species diversity, and this can be explained by increasing rainfall during the warmest months of the year (and therefore in plant productivity) with increasing latitude. The sensitivity of Cerrado ant diversity to declining rainfall contrasts with the high resilience to aridity of the Australian savanna ant fauna, and this reflects the contrasting evolutionary histories of these faunas. Our findings highlight the importance of historical processes as drivers of intercontinental contrasts in macroecological patterns. [ABSTRACT FROM AUTHOR]

The acacia rat Thallomys paedulcus is a small arboreal rodent, extensively dependent on Acacia sp. trees. In order to understand the arboreal locomotor adaptations of the species, we examined their gaits in arboreal locomotion (i.e. diagonality, duty factor, duty factor index, velocity, and stride length and frequency). For these purposes, we filmed 12 captive specimens on simulated arboreal substrates of variable sizes (2 mm, 5 mm, 10 mm, 25 mm) and inclinations (0° and 45°). Acacia rats employed slow, symmetrical gaits with lower diagonality on the smaller substrates, which were progressively substituted by faster, asymmetrical half-bounding gaits on larger substrates. In general, inclination had no impact on gait metrics, except that ascents were slower than horizontal locomotion. Velocity increase was regulated primarily due to an increase in stride frequency, a pattern encountered in many small mammals, although stride length contributed significantly as well. These locomotor adaptations serve as a behavioural mechanism to cope with the challenges of the arboreal milieu. They appear to provide stability and enable safe negotiation of arboreal substrates, ultimately leading to the successful exploitation of Acacia trees in their natural habitat. [ABSTRACT FROM AUTHOR]

Aim We tested the 'habitat amount hypothesis', which predicts that the effect of patch size on number of species results from a 'sample area effect' rather than an 'island effect'. Specifically, we (1) compared parameters of the species-area relationship ( SAR) of arboreal mammals in forested fluvial islands and continuous forest, and (2) separated the effects of island size and of landscape-scale habitat amount on species richness. Location Middle-Solimões River region, Central Amazon. Methods We surveyed arboreal mammals along line-transects on 15 fluvial floodplain islands and nine transects in continuous floodplain forest. Transect length varied according to island size. Transects of similar length were established in continuous forest. We used power transformed (log-log) models to construct a SAR for the set of island transects and another SAR for the set of continuous forest transects. We compared slope and intercept between the two SARs using ANCOVA. We used multiple regressions to separate the effects of island size and of habitat amount on the rarefied number of species across multiple spatial scales (500-6,000 m). Results The two species-area curves showed similar slopes, but the intercept was lower for islands. Multiple regressions showed the best fit at the 5,500 m spatial scale. At this scale, habitat amount predicted species richness, whereas island size did not. Main conclusions We conclude that the apparent effect of patch size on the number of species may be simply due to the sample area effect and that no island effect operates on this patchy system. Accordingly, island size per se does not increase the number of species at a sample site. Fluvial islands should not be treated as 'real' islands from the island biogeography perspective. In sum, we found support for the habitat amount hypothesis for predicting the richness of arboreal mammals on fluvial islands. [ABSTRACT FROM AUTHOR]

The feet are the only contact between the body and the substrate in limbed animals and as such they provide a crucial interface between the animal and its environment. This is especially true for bipedal and arboreal species living in a complex three-dimensional environment that likely induces strong selection on foot morphology. In birds, foot morphology is highly variable, with different orientations of the toes, making it a good model for the study of the role of functional, developmental, and phylogenetic constraints in the evolution of phenotypic diversity. Our data on the proportions of the phalanges analyzed in a phylogenetic context show that two different morphological patterns exist that depend mainly on habitat and toe orientation. In the anisodactyl foot, the hallux is the only backward-oriented toe and is enlarged in climbing species and reduced in terrestrial ones. Moreover, a proximo-distal gradient in phalanx size is observed depending on the degree of terrestriality. In the two other cases (heterodactyl and zygodactyl) that have two toes that point backward, the hallux is rather small in contrast to the other backward-pointing toe, which is enlarged. The first pattern is convergent and common among tetrapods and follows rules of skeletal development. The second pattern is unique for the clade and under muscle-morphogenetic control. In all cases, the functional result is the same tool, a pincer-like foot. [ABSTRACT FROM AUTHOR]

Unprecedented global human population growth and rapid urbanization of rural and natural lands highlight the urgent need to integrate biodiversity conservation into planning for urban growth. A challenging question for applied ecologists to answer is: What pattern of urban growth meets future housing demand whilst minimizing impacts on biodiversity?, We quantified the consequences for mammals of meeting future housing demand under different patterns of compact and dispersed urban growth in an urbanizing forested landscape in south-eastern Australia. Using empirical data, we predicted impacts on mammals of urban growth scenarios that varied in housing density (compact versus dispersed) and location of development for four target numbers of new dwellings., We predicted that compact developments (i.e. high-density housing) reduced up to 6% of the area of occupancy or abundance of five of the six mammal species examined. In contrast, dispersed developments (i.e. low-density housing) led to increased mammal abundance overall, although results varied between species: as dwellings increased, the abundance or occurrence of two species increased (up to ∼100%), one species showed no change, and three species declined (up to ∼39%)., Two ground-dwelling mammal species ( Antechinus stuartii and Rattus fuscipes) and a tree-dwelling species ( Petaurus australis) were predicted to decline considerably under dispersed rather than compact development. The strongest negative effect of dispersed development was for Petaurus australis (a species more abundant in forested interiors) which exhibited up to a 39% reduction in abundance due to forest loss and an extended negative edge effect from urban settlements into adjacent forests., Synthesis and applications. Our findings demonstrate that, when aiming to meet demand for housing, any form of compact development (i.e. high-density housing) has fewer detrimental impacts on forest-dwelling mammals than dispersed development (i.e. low-density housing). This is because compact development concentrates the negative effects of housing into a small area whilst at the same time preserving large expanses of forests and the fauna they sustain. Landscape planning and urban growth policies must consider the trade-off between the intensity of the threat and area of sprawl when aiming to reduce urbanization impacts. [ABSTRACT FROM AUTHOR]

The means of orientation is studied in the Vietnamese pygmy dormouse Typhlomys chapensis, a poorly known enigmatic semi-fossorial semi-arboreal rodent. Data on eye structure are presented, which prove that Typhlomys (translated as 'the blind mouse') is incapable of object vision: the retina is folded and retains no more than 2500 ganglion cells in the focal plane, and the optic nerve is subject to gliosis. Hence, Typhlomys has no other means for rapid long-range orientation among tree branches other than echolocation. Ultrasonic vocalization recordings at the frequency range of 50-100 kHz support this hypothesis. The vocalizations are represented by bouts of up to 7 more or less evenly-spaced and uniform frequency-modulated sweep-like pulses in rapid succession. Structurally, these sweeps are similar to frequency-modulated ultrasonic echolocation calls of some bat species, but they are too faint to be revealed with a common bat detector. When recording video simultaneously with the ultrasonic audio, a significantly greater pulse rate during locomotion compared to that of resting animals has been demonstrated. Our findings of locomotion-associated ultrasonic vocalization in a fast-climbing but weakly-sighted small mammal ecotype add support to the 'echolocation-first theory' of pre-flight origin of echolocation in bats. [ABSTRACT FROM AUTHOR]

Aim Grammomys are mostly arboreal rodents occurring in forests, woodlands and thickets throughout sub-Saharan Africa. We investigated whether the divergence events within the genus follow the existing evolutionary scenario for the development of African forests since the late Miocene. Location Sub-Saharan African forests and woodlands. Methods We inferred the molecular phylogeny of Grammomys using Bayesian and maximum likelihood methods and DNA sequences of 351 specimens collected from across the distribution of the genus. We mapped the genetic diversity, estimated the divergence times by a relaxed clock model and compared evolution of the genus with forest history. Results Phylogenetic analysis confirms the monophyly of Grammomys and reveals five main Grammomys lineages with mainly parapatric distributions: (1) the poensis group in Guineo-Congolese forests; (2) the selousi group with a distribution mainly in coastal forests of southern and eastern Africa; (3) the dolichurus group restricted to the easternmost part of South Africa; (4) the macmillani group in the northern part of eastern and Central Africa with one isolated species in Guinean forests; and (5) the surdaster group, widely distributed in eastern Africa south of the equator. Every group contains well supported sublineages suggesting the existence of undescribed species. The earliest split within the genus (groups 1 vs. 2-5) occurred in the late Miocene and coincides with the formation of the Rift Valley which resulted in the east-west division of the initially pan-African forest. The subsequent separation between groups (2 vs. 3-5) also dates to the end of the Miocene and suggests the split between Grammomys from coastal to upland forests in eastern Africa followed by a single dispersal event into western Africa during the Pleistocene. Conclusions The evolutionary history of the genus Grammomys closely reflects the accepted scenario of major historical changes in the distribution of tropical African forests since the late Miocene. [ABSTRACT FROM AUTHOR]

Spatially explicit models of animal abundance are a critical tool to inform conservation planning and management. However, they require the availability of spatially diffuse environmental predictors of abundance, which may be challenging, especially in complex and heterogeneous habitats. This is particularly the case for tropical mammals, such as nonhuman primates, that depend on multi-layered and species-rich tree canopy coverage, which is usually measured through a limited sample of ground plots. We developed an approach that calibrates remote-sensing imagery to ground measurements of tree density to derive basal area, in turn used as a predictor of primate density based on published models. We applied generalized linear models ( GLM) to relate 9.8-ha ground samples of tree basal area to various metrics extracted from Landsat 8 imagery. We tested the potential of this approach for spatial inference of animal density by comparing the density predictions for an endangered colobus monkey, to previous estimates from field transect counts, measured basal area, and other predictors of abundance. The best GLM had high accuracy and showed no significant difference between predicted and observed values of basal area. Our species distribution model yielded predicted primate densities that matched those based on field measurements. Results show the potential of using open-access and global remote-sensing data to derive an important predictor of animal abundance in tropical forests and in turn to make spatially explicit inference on animal density. This approach has important, inherent applications as it greatly magnifies the relevance of abundance modeling for informing conservation. This is especially true for threatened species living in heterogeneous habitats where spatial patterns of abundance, in relation to habitat and/or human disturbance factors, are often complex and, management decisions, such as improving forest protection, may need to be focused on priority areas. [ABSTRACT FROM AUTHOR]

Cursorial central-place foragers like ants are expected to minimize travel costs by choosing the least resistive pathways to food resources. Tropical arboreal and semi-arboreal ants locomote over a variety of plant surfaces, and their choice of pathways is selective. We measured the roughness of tree trunk and liana stem surfaces using laser scanning technology, and explored its consequences for running speed in various ant taxa. The average amplitude of tree trunk surface roughness differed interspecifically, and ranged from 1.4-2.2 mm among three common tree species ( Anacardium excelsum, Alseis blackiana, and Dipteryx panamensis). The roughness of liana stems also varied interspecifically (among Tontelea ovalifolia, Bauhinia sp. and Paullinia sp.) and was an order of magnitude lower than tree surface roughness (mean amplitude ranged 0.09-0.19 mm). Field observations of various ant species foraging on tree trunks and liana stems, and on dowels covered with sandpaper, showed that their running speed declined with increasing amplitude of roughness. The effect of roughness on running speed was strongest for mid-sized ants ( Azteca trigona and Dolichoderus bispinosus). The accumulation rate of ants at baits did not vary with tree surface roughness, but was significantly lower on moss-covered versus moss-free bark. Collectively, these results indicate that the quality of plant substrates can influence the foraging patterns of arboreal ants, but likely is more important for resource discovery than for dominance on bare tree surfaces. [ABSTRACT FROM AUTHOR]

A major goal of community ecology is to identify the patterns of species associations and the processes that shape them. Arboreal ants are extremely diverse and abundant, making them an interesting and valuable group for tackling this issue. Numerous studies have used observational data of species co-occurrence patterns to infer underlying assembly processes, but the complexity of these communities has resulted in few solid conclusions. This study takes advantage of an observational dataset that is unusually well-structured with respect to habitat attributes (tree species, tree sizes, and vegetation structure), to disentangle different factors influencing community organization. In particular, this study assesses the potential role of interspecific competition and habitat selection on the distribution patterns of an arboreal ant community by incorporating habitat attributes into the co-occurrence analyses. These findings are then contrasted against species traits, to explore functional explanations for the identified community patterns. We ran a suite of null models, first accounting only for the species incidence in the community and later incorporating habitat attributes in the null models. We performed analyses with all the species in the community and then with only the most common species using both a matrix-level approach and a pairwise-level approach. The co-occurrence patterns did not differ from randomness in the matrix-level approach accounting for all ant species in the community. However, a segregated pattern was detected for the most common ant species. Moreover, with the pairwise approach, we found a significant number of negative and positive pairs of species associations. Most of the segregated associations appear to be explained by competitive interactions between species, not habitat affiliations. This was supported by comparisons of species traits for significantly associated pairs. These results suggest that competition is the most important influence on the distribution patterns of arboreal ants within the focal community. Habitat attributes, in contrast, showed no significant influence on the matrix-wide results and affected only a few associations. In addition, the segregated pairs shared more biological characteristic in common than the aggregated and random ones. [ABSTRACT FROM AUTHOR]

Objectives The proximate and ultimate determinants that may have prompted some primates to shift from an arboreal to terrestrial feeding niche, whether due to environmental change, seasonality, and/or predation pressure, are poorly understood. Within a fragmented littoral forest in southeast Madagascar, an arboreal strepsirrhine population spends a large proportion of time on the ground, thus we aimed to identify which factors influence terrestrial feeding. Methods From January to December 2013, we conducted 103 full-day focal follows on three social groups of southern bamboo lemurs H. meridionalis. We continuously recorded feeding time on all arboreal and terrestrial items, as well as whether the focal individual was under the canopy or exposed, and the distance to their nearest conspecific neighbor. All observed food items were collected and analyzed for macronutrient content. Daily climatic variables (temperature, precipitation), resource seasonality, daily path length (DPL), along with dietary and predation risk proxies, were used as fixed effects in a linear mixed model, with the daily proportion of terrestrial feeding as the dependent variable. Results Our model indicated that daily terrestrial feeding increased at cooler temperature, was associated with reduced DPL, and the intake of dietary metabolizable energy increased as terrestrial feeding increased. All other fixed effects were not significant predictors. Discussion Our study provides a window into the ultimate determinants of niche expansion: ancestral primates, in absence of their primary resources, may have initially descended to the ground in peripheral population range areas where the benefits (e g., nutritional pay-off) out-weighed the costs. [ABSTRACT FROM AUTHOR]

Defoliation of forest tree canopies by herbivores and other agents, leading to tree mortality and reduced productivity, threatens the ecological stability of forests globally. This study shows that long-term control of a mammalian arboreal folivore (brushtail possums; Trichosurus vulpecula Phalangeridae) reduces crown dieback and increases foliage cover in browsing-damaged canopy trees. We monitored indices of possumdensity, possumbrowsing, tree foliage cover and crown dieback for 20 years following initiation of possum control in 1994 that repeatedly reduced possum densities to near zero every 5-6 years and kept the population below 35% of pre-control levels over the entire period. Observable possum browsing was recorded on 20-49% of individuals of three palatable tree species at the time of first control. Those percentages fell to zero after control and never exceeded 2-10% for individual species over the next 19 years. We recorded significant increases in foliage cover attributable to recovery from defoliation by possums for all three species during the first 10 years. Large increases in foliage cover occurred on individuals that were heavily browsed in 1994 (mean increases: 36-89%), but mean population increases were modest (3-19%) because only 10-19%of trees were initially heavily browsed. Twenty-year mortality rates were similar for plants with, or without, initial possumbrowsing, indicating no residual impact of pre-control browsing on tree mortality. Times for full recovery of crown foliage cover varied from 10 years for the youngest trees and faster growing species to more than 20 years for mature individuals of the slowest growing species. [ABSTRACT FROM AUTHOR]

Maturation includes physical, reproductive, and social aspects that develop asynchronously. Intra- and inter-individual variation in the relative timing of each aspect reflects context-dependent plasticity. Plasticity in developmental timing may be important for the family-living small apes (family Hylobatidae), where reproductive opportunities are monopolized by territorial breeding pairs. Data on development in hylobatids are so far limited due to their elusive arboreal niche and long lifespans. Herein, we provide the first quantitative analysis of behavioral development in 14 captive individuals of three species ( Hylobates moloch, Nomascus leucogenys, and Symphalangus syndactylus), with some individuals being observed over 8 years. To establish a baseline for behavioral development, we compare the behavior of infants (0-2 years), juveniles (2-4 years), adolescents (4-6 years), and subadults (6-9 years) in their natal groups from data obtained over 250 focal observation hours. We then relate changes in behavior to measures of somatic and physiological development, and to wild populations, to identify the degree of intra- and inter-individual variation in developmental timing. We found greater concordance between behavioral and physiological markers of weaning than between different markers of later development, and the timing of later milestones varied more among individuals. Behavioral estimates from both captive and wild individuals in their natal groups indicate that puberty begins close to age 5, but physiological maturation can occur 0.5-3 years earlier in captive individuals than in wild individuals. Ages at onset of puberty, sexual, and social maturation vary in both captive and wild populations. The available evidence indicates that the social environment during development (e.g., presence of breeding female and appropriate mating partner), as well as nutrition, play a role in the timing of life history transitions in hylobatids. Am. J. Primatol. 78:610-625, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Woodland and forest degradation, driven predominately by agricultural and pastoral production, is a crisis facing many species globally, in particular hollow-dependent fauna. Large predatory species play important roles in both ecosystems and conservation strategies, but few studies have examined habitat selection of such species in intensively human-modified landscapes. We quantified habitat selection and resource use by a large, top-order and threatened snake (carpet python, M orelia spilota), between adjacent areas of high and low anthropogenic modification in inland Australia, a region that has undergone considerable alteration since European settlement. At the low-impact site, snakes preferred tree hollows and a structurally complex understorey, whereas at the high-impact site, snakes preferred homestead attics. Based on the decline of the species in this region, however, high-impact landscapes may only support snakes when they are adjacent to low-impact habitats. Invasive species comprised a large part of snake diets in both landscape types. Carpet pythons, with large home ranges and habitat requirements that overlap with many smaller threatened mammalian and avian fauna, are generally well liked and easily identifiable by rural landholders. Accordingly, they may play a key role in conservation strategies aimed at the protection of woodland and hollow-dependent fauna in heavily modified landscapes of Australia's inland regions. However, invasive species, which tend to contribute to declines in native species inhabiting arid and semi-arid Australia, are beneficial and important to pythons. Our study therefore highlights the diversity of effects that two major threats to biodiversity - habitat loss and invasive species - can have on different species within the same ecosystem. [ABSTRACT FROM AUTHOR]

Disturbance is a crucial determinant of animal abundance, distribution and community structure in many ecosystems, but the ways in which multiple disturbance types interact remain poorly understood. The effects of multiple-disturbance interactions can be additive, subadditive or super-additive (synergistic). Synergistic effects in particular can accelerate ecological change; thus, characterizing such synergies, the conditions under which they arise, and how long they persist has been identified as a major goal of ecology., We factorially manipulated two principal sources of disturbance in African savannas, fire and elephants, and measured their independent and interactive effects on the numerically dominant vertebrate (the arboreal gekkonid lizard Lygodactylus keniensis) and invertebrate (a guild of symbiotic Acacia ants) animal species in a semi-arid Kenyan savanna., Elephant exclusion alone (minus fire) had negligible effects on gecko density. Fire alone (minus elephants) had negligible effects on gecko density after 4 months, but increased gecko density twofold after 16 months, likely because the decay of fire-damaged woody biomass created refuges and nest sites for geckos. In the presence of elephants, fire increased gecko density nearly threefold within 4 months of the experimental burn; this occurred because fire increased the incidence of elephant damage to trees, which in turn improved microhabitat quality for geckos. However, this synergistic positive effect of fire and elephants attenuated over the ensuing year, such that only the main effect of fire was evident after 16 months., Fire also altered the structure of symbiotic plant-ant assemblages occupying the dominant tree species ( Acacia drepanolobium); this influenced gecko habitat selection but did not explain the synergistic effect of fire and elephants. However, fire-driven shifts in plant-ant occupancy may have indirectly mediated this effect by increasing trees' susceptibility to elephant damage., Our findings confirm the importance of fire × elephant interactions in structuring arboreal wildlife populations. Where habitat modification by megaherbivores facilitates co-occurring species, fire may amplify these effects in the short term by increasing the frequency or intensity of herbivory, leading to synergy. In the longer term, tree mortality due to both top kill by fire and toppling by large herbivores may reduce overall microhabitat availability, eliminating the synergy. [ABSTRACT FROM AUTHOR]

Orangutans (genus Pongo) are the largest arboreal mammals, but Bornean orangutans ( P. pygmaeus spp.) also spend time on the ground. Here, we investigate ground use among orangutans using 32,000 hr of direct focal animal observations from a well-habituated wild population of Bornean orangutans ( P. p. wurmbii) living in a closed-canopy swamp forest at Tuanan, Central Kalimantan, Indonesia. Ground use did not change with increasing observation time of well-habituated individuals, suggesting it was not an artifact of observer presence. Flanged males spent the most time on the ground (ca. 5% of active time), weaned immatures the least (around 1%). Females and immatures descended mainly to feed, especially on termites, whereas flanged males traveled more while on the ground. Flanged males may travel more inconspicuously, and perhaps also faster, when moving on the ground. In addition, orangutans engaged in ground-specific behavior, including drinking from and bathing in swamp pools. Supplementary records from 20 ground-level camera traps, totaling 3986 trap days, confirmed the observed age-sex biases in ground use at Tuanan. We conclude that ground use is a natural part of the Bornean orangutan behavioral repertoire, however it remains unclear to what extent food scarcity and canopy structure explain population differences in ground use. Am. J. Primatol. 77:1216-1229, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

We present a comparative analysis of the morphological and reproductive characteristics of adult female Anolis nebulosus, an arboreal lizard found on both mainland and insular habitats near the Pacific Coast of Mexico. Females from San Pancho Island were larger in all measured morphological variables than females from Biological Field Station Chamela ( BFSCH) on the mainland, and those also reproduced at smaller body size (snout-vent length, SVL: range = 35-44 [ABSTRACT FROM AUTHOR]

Mandrills ( Mandrillus sphinx) are enigmatic Old World primates whose social organization and ecology remain poorly known. Previous studies indicated, for example, that groups are composed of only adult females and their young or that several units composed of one adult male and several females make up larger permanent social units. Here, we present the first data on group composition and male ranging patterns from the only habituated wild mandrill group and examine how home range size and daily path length varied with environmental and demographic factors over a 15-month period. Our study site is located in southern Gabon where we followed the group on a daily basis, collecting data on presence, ranging, behavior, and parasite load of its individual members. Throughout the study, the group was made up of about 120 individuals, including several non-natal and natal adult and sub-adult males. One-male units were never observed. The mandrills traveled an estimated 0.44-6.50 km/day in a home range area of 866.7 ha. Exploratory analyses revealed that precipitation, the number of adult males present, and the richness of protozoan parasites were all positively correlated with daily path length. These results clarify the social system of mandrills and provide first insights into the factors that shape their ranging patterns. Am. J. Primatol. 77:1036-1048, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The earlier typifications of 12 names of Tamarix ( T. arabica, T. aralensis, T. boveana, T. chinensis, T. hohenackeri, T. karelinii, T. kotschyi, T. leptopetala, T. laxa var. araratica, T. laxa var. subspicata, T. mannifera var. persica and T. pycnocarpa) are discussed. In eight cases, a second-step lectotype was selected, because several specimens of the type collection were found at the herbaria where the first-step lectotypes were indicated. Five previous indications of holotypes were corrected to lectotype designations, as no particular specimens had been explicitly mentioned in the protologue. The typifications of T. hampeana and T. mascatensis are clarified. Moreover, four additional names ( T. bengalensis, T. gallica var. arborea, T. mannifera var. purpurascens and T. passerinoides var. macrocarpa) are lectotypified, and an epitype is selected for T. pallasii var. macrostemon. Lectotypes are designated from the material present at G-BOIS, P, P-LOUR, PRC, and W. Most of the 19 names treated in this work were described in the 18th and 19th centuries by important European botanists such as Bunge (12), Boissier (1), Candolle (1), Ehrenberg (3) and Loureiro (1). [ABSTRACT FROM AUTHOR]

Predator effects on herbivores are often referred to as examples of biotic interactions that weaken with latitude, but more studies are needed to test for the generality of this pattern. To further the understanding of large-scale geographical patterns in abundance and diversity of predatory arthropods, from 2008-2011 we explored spider communities in the canopies of primary forest trees of the boreal zone ( Pinus sylvestris, Picea abies, Betula pubescens and B. pendula) along five latitudinal gradients in northern Europe, from 59 to 70°N and from 10 to 60°E. The abundance of arboreal spiders in Norway and Finland was about a half of that in Russia, presumably due to more intensive forest management in Scandinavia. The abundance, taxonomic and functional diversity of arboreal spiders generally decreased with latitude; however, actual weather conditions during the study years had little effect on this pattern. Coniferous species supported higher abundance and diversity of arboreal spiders than birches, but the poleward decrease in either abundance or taxonomic diversity of arboreal spiders did not differ between coniferous and deciduous tree species. In contrast, functional diversity on birches decreased with latitude greater than on coniferous trees. Euryphagous spiders showed stronger decrease with latitude in terms of both abundance and taxonomic diversity than more specialized (steno- and oligophagous) spiders. We attribute the general decrease in density and diversity of spiders with latitude to an increased pressure from apex predators (birds) rather than to direct effects of climate or changes in prey abundance. The abundance of spiders declined with the latitude to the greater extent than the densities of their potential prey did, suggesting a decrease in the strength of predator-prey interactions towards the north. [ABSTRACT FROM AUTHOR]

Ongoing habitat loss and fragmentation is considered a threat to biodiversity as it can create small, isolated populations that are at increased risk of extinction. Tree-dependent species are predicted to be highly sensitive to forest and woodland loss and fragmentation, but few studies have tested the influence of different types of landscape matrix on gene flow and population structure of arboreal species. Here, we examine the effects of landscape matrix on population structure of the sugar glider ( Petaurus breviceps) in a fragmented landscape in southeastern South Australia. We collected 250 individuals across 12 native Eucalyptus forest remnants surrounded by cleared agricultural land or exotic Pinus radiata plantations and a large continuous eucalypt forest. Fifteen microsatellite loci were genotyped and analyzed to infer levels of population differentiation and dispersal. Genetic differentiation among most forest patches was evident. We found evidence for female philopatry and restricted dispersal distances for females relative to males, suggesting there is male-biased dispersal. Among the environmental variables, spatial variables including geographic location, minimum distance to neighboring patch, and degree of isolation were the most important in explaining genetic variation. The permeability of a cleared agricultural matrix to dispersing gliders was significantly higher than that of a pine matrix, with the gliders dispersing shorter distances across the latter. Our results added to previous findings for other species of restricted dispersal and connectivity due to habitat fragmentation in the same region, providing valuable information for the development of strategies to improve the connectivity of populations in the future. [ABSTRACT FROM AUTHOR]

Ecological disturbance and climate are key drivers of temporal dynamics in the demography and genetic diversity of natural populations. Microscale refuges are known to buffer species' persistence against environmental change, but the effects of such refuges on demographic and genetic patterns in response to short-term environmental variation are poorly understood. We quantified demographic and genetic responses of mountain brushtail possums ( Trichosurus cunninghami) to rainfall variability (1992-2013) and to a major wildfire. We hypothesized that there would be underlying differences in demographic and genetic processes between an unburnt mesic refuge and a topographically exposed zone that was burnt in 2009. Fire caused a 2-year decrease in survival in the burnt zone, but the population grew after the fire due to immigration, leading to increased expected heterozygosity. We documented a fire-related behavioural shift, where the rate of movement by individuals in the unburnt refuge to the burnt zone decreased after fire. Irrespective of the fire, there were long-term differences in demographic and genetic parameters between the mesic/unburnt refuge and the nonmesic/burnt zone. Survival was high and unaffected by rainfall in the refuge, but lower and rainfall-dependent in the nonmesic zone. Net movement of individuals was directional, from the mesic refuge to the nonmesic zone, suggesting fine-scale source-sink dynamics. There were higher expected heterozygosity ( HE) and temporal genetic stability in the refuge, but lower HE and marked temporal genetic structure in the exposed habitat, consistent with reduced generational overlap caused by elevated mortality and immigration. Thus, fine-scale refuges can mediate the short-term demographic and genetic effects of climate and ecological disturbance. [ABSTRACT FROM AUTHOR]

A study of succession of ant species in plantations of different ages and development may assist with our understanding of the dynamics of their assemblages. The aim of this study was to characterise the relationship between development of Brazilian cocoa plantations and the nature of their dominant ant assemblages. A chronosequence of cocoa plantations aged 1, 3, 4, 8, 15 and 33 years was sampled by several methodologies. Data were analysed in terms behavioural dominance and Berger- Parker's dominance index (here based on frequency data), and also by principal component analysis and analysis of co-occurrence. Apart from lower numbers of species being found in the 1-year-old plantation, there was no consistent trend in ant richness with plantation age. According to the criteria we adopted, only one species reached behavioural dominance in most age classes of plantation, although this increased to three in the 8-year-old one, before declining to zero in the oldest plantation. No species reached Berger- Parker's dominance in the youngest plantation, whereas all other age classes contained one to three dominants. Particular species showed non-age-related variations in their degree of Berger- Parker's dominance and this could in part be related to which species initially colonised the plantation. Principal component analysis axis 1 was partly related to plantation age, indicating an age-related change in assemblage composition. Ant species co-occurrence could only be effectively detected in cocoa plantations from 3 to 15 years of age. The arboreal ant assemblage is dynamic in nature, with the competitive hierarchy among species oscillating along the cocoa development chronosequence. The assemblage structure could be influenced by the initial founding ants, as well as by the invasive M onomorium floricola. [ABSTRACT FROM AUTHOR]

Aim Highly productive areas have long been hypothesized to support a greater abundance and diversity of animals than less productive areas. However, evidence for this is equivocal and, until recently, has been difficult to test at a landscape level. For the first time, we use imaging spectroscopy to investigate the relationship between plant productivity and arboreal mammal species richness and abundance at a landscape scale. Location A eucalypt forest in New South Wales, Australia. Methods Using a common index of plant productivity - normalized difference vegetation index ( NDVI) - as a proxy for available energy, we test the ability of species-energy theory and optimal foraging theory to explain variations in arboreal marsupial species richness and abundance. We obtained NDVI data from an airborne imaging spectrophotometer. Results Species richness increased in relation to NDVI among 53 eucalypt forest sites, based on five arboreal marsupial species. The presence and abundance of a eucalypt folivore specialist, Petauroides volans, increased in relation to NDVI. The relative abundance of all arboreal marsupials collectively also increased in relation to NDVI among sites, even with P. volans data excluded. In support of optimal foraging theory, the observed locations of P. volans had a higher NDVI value than the average for sampling transects. In addition, the average NDVI of eucalypt forest remnants was positively related to the overall abundance of P. volans. An important caveat is that NDVI did not explain all the variation in arboreal marsupial populations. Main conclusions Assuming that NDVI is an appropriate proxy for available energy in a eucalypt forest, our results are consistent with predictions from species-energy and optimal foraging theories. Remotely sensed measures of productivity and forage quality, used in conjunction with other important landscape characteristics, provide a potentially powerful tool to evaluate habitat and biodiversity hotspots at scales relevant to wildlife management and conservation. [ABSTRACT FROM AUTHOR]

ABSTRACT The nightly construction of arboreal sleeping platforms or 'nests' has been observed among every great ape population studied to date. However, this behavior has never been reported in any other nonhuman primate and comparisons between ape and monkey sleep illuminate the link between sleeping substrates, positional behavior, and sleep efficiency. Here, we compare sleep depth and efficiency and night-time positional behavior between a large-bodied cercopithecoid ( Papio papio) and a large-bodied hominoid ( Pongo spp.) at the Indianapolis Zoo. We used infrared videography to assess nightly sleep and awake behavioral states, gross body movements, and postures in baboons ( N = 45 nights) and orangutans ( N = 128 nights). We calculated the total waking time, total sleep time, sleep fragmentation (the number of brief awakenings ≥2 min/h), sleep motor activity (number of motor activity bouts per hour), sleep efficiency (sleep duration/time in bed), and percentage of time spent in each posture. By every measure, orangutans experienced overall deeper, more efficient sleep. Baboons were more likely to sleep in guarded, upright positions (weight bearing on their ischial callosities) and never opted to use additional materials to augment sleep environments, whereas orangutans slept in insouciant, relaxed positions on constructed sleeping materials. Our results suggest that relaxed sleeping postures may have been enabled by sleeping platforms as a behavioral facilitator to sleep, which could have allowed for greater sleep depth and next-day cognitive capacities in both great apes and hominins. Am J Phys Anthropol 157:421-427, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Tree-cavity-dependent wildlife faces future shortages of cavities due to a decline in the abundance of large, old trees in many parts of the world. Nest boxes are proposed as a tool to restore habitat value but evidence of their effectiveness for arboreal mammals remains equivocal. This may arise from a poor understanding of design preferences. We conducted investigations in two landscapes in eastern Australia to determine whether species show a preference for specific designs. We observed a preference by some mammal species for particular designs (33-78% occupied/used), suggesting that design refinement can improve the frequency with which nest boxes are used. Although feral species may out-compete target species for nest boxes, we did not observe this. We recorded feral honeybees ( Apis mellifera) in 6-9% of nest boxes but they did not remain, and many occupied boxes were later used by mammals. The introduced common myna bird ( Acridotheres tristis) was prevalent in one landscape, but competition for nest boxes was localized. For nest boxes to be an effective habitat restoration tool, they must be able to be occupied over long periods of time. We investigated this for the squirrel glider ( Petaurus norfolcensis), an arboreal marsupial threatened through part of its geographic range. Squirrel gliders occupied and bred within nest boxes (100% used) at two locations continuously over a 10-year period with minimal nest box maintenance. Individuals occupied boxes for up to 7 years. This confirms that targeted nest box programs can be an effective restoration tool for cavity-dependent arboreal mammals. [ABSTRACT FROM AUTHOR]

Climate change in the UK is predicted to increase both winter temperatures and the frequency of summer drought events. Elatobium abietinum, the green spruce aphid, is the most important defoliating pest of Sitka spruce, Picea sitchensis, a conifer very widely used in British forest industry. This aphid is expected to respond strongly to altered climate, with changes to population densities leading to more frequent serious outbreaks and defoliation. The impact of simulated spring-summer drought on the reproductive performance of E. abietinum was investigated under laboratory conditions. Rates were assessed under five drought treatments of differing frequencies and intensities to characterize the direction of responses under different drought scenarios, and in time-staggered trials to explore seasonal variation. Variation in the response of reproduction to water deficit was mediated by drought frequency and magnitude. Low-amplitude, moderate intermittent stress improved reproductive rates, while severe stress, both continuous and high-amplitude intermittent, had a detrimental impact when compared with observations made on well-watered controls. Season was also found to modify the response, with improvements to plant nutritional quality under high-amplitude stress reflected by improving reproduction. Despite this, no differences in rates were found during the autumn, suggesting no advancement in spruce dormancy under drought. Drought stress therefore has the potential to alter E. abietinum population densities, structure and phenology in Sitka spruce plantations, with implications for forest management, damage levels and natural control of the aphid under future altered climate. [ABSTRACT FROM AUTHOR]

ABSTRACT Despite the importance that concepts of arboreal stability have in theories of primate locomotor evolution, we currently lack measures of balance performance during primate locomotion. We provide the first quantitative data on locomotor stability in an arboreal primate, the common marmoset ( Callithrix jacchus), predicting that primates should maximize arboreal stability by minimizing side-to-side angular momentum about the support (i.e., Lsup). If net Lsup becomes excessive, the animal will be unable to arrest its angular movement and will fall. Using a novel, highly integrative experimental procedure we directly measured whole-body Lsup in two adult marmosets moving along narrow (2.5 cm diameter) and broad (5 cm diameter) poles. Marmosets showed a strong preference for asymmetrical gaits (e.g., gallops and bounds) over symmetrical gaits (e.g., walks and runs), with asymmetrical gaits representing >90% of all strides. Movement on the narrow support was associated with an increase in more 'grounded' gaits (i.e., lacking an aerial phase) and a more even distribution of torque production between the fore- and hind limbs. These adjustments in gait dynamics significantly reduced net Lsup on the narrow support relative to the broad support. Despite their lack of a well-developed grasping apparatus, marmosets proved adept at producing muscular 'grasping' torques about the support, particularly with the hind limbs. We contend that asymmetrical gaits permit small-bodied arboreal mammals, including primates, to expand 'effective grasp' by gripping the substrate between left and right limbs of a girdle. This model of arboreal stability may hold important implications for understanding primate locomotor evolution. [ABSTRACT FROM AUTHOR]

Conversion of forests to anthropogenic land-uses increasingly subjects chimpanzee populations to habitat changes and concomitant alterations in the plant resources available to them for nesting and feeding. Based on nest count surveys conducted during the dry season, we investigated nest tree species selection and the effect of vegetation attributes on nest abundance of the western chimpanzee, Pan troglodytes verus, at Lagoas de Cufada Natural Park (LCNP), Guinea-Bissau, a forest-savannah mosaic widely disturbed by humans. Further, we assessed patterns of nest height distribution to determine support for the anti-predator hypothesis. A zero-altered generalized linear mixed model showed that nest abundance was negatively related to floristic diversity (exponential form of the Shannon index) and positively with the availability of smaller-sized trees, reflecting characteristics of dense-canopy forest. A positive correlation between nest abundance and floristic richness (number of plant species) and composition indicated that species-rich open habitats are also important in nest site selection. Restricting this analysis to feeding trees, nest abundance was again positively associated with the availability of smaller-sized trees, further supporting the preference for nesting in food tree species from dense forest. Nest tree species selection was non-random, and oil palms were used at a much lower proportion (10%) than previously reported from other study sites in forest-savannah mosaics. While this study suggests that human disturbance may underlie the exclusive arboreal nesting at LCNP, better quantitative data are needed to determine to what extent the construction of elevated nests is in fact a response to predators able to climb trees. Given the importance of LCNP as refuge for Pan t. verus our findings can improve conservation decisions for the management of this important umbrella species as well as its remaining suitable habitats. Am. J. Primatol. 77:186-199, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article explores the arboreal habitat of Hyla versicolor complex (Hylidae) at 30-40 m tall, super-canopy Pinus strobus (white pine). It states that Reconyx cameras were installed at three different canopy heights and species were identified on bases of factors such as size, distribution and vocalizations. Two distinct types of variation in the microclimatic conditions of upper canopies, including H. versicolor's activity at night and day, were observed.

The evolution of arboreality in snakes is accompanied by modifications that are remarkably similar across species. Gravity is one of the most important selective agents, and arboreal snakes present adaptations to circumvent the gradient of pressure, including modifications on heart position ( HP) and body slenderness ( BS). However, the degree to which different life-history traits influence the cardiovascular system of snakes remains unclear. Here, we used an ecological and a phylogenetic approach to explore the relationship between habitat, HP, BS, and heart size ( HS) in five species of the neotropical whipsnakes genus Chironius that occupy terrestrial, semiarboreal, and arboreal habits. Our ecological comparison indicated that the arboreal species have the most posterior-positioned heart, the most slender body, and the smallest HS, whereas the terrestrial representative of the group exhibited the most anterior heart, the less flattened body, and the largest HS. After removing the phylogenetic effect, we found no difference in HP and BS between terrestrial and arboreal species. Habitat only differed when contrasting with HS. Body slenderness and HS were correlated with HP. Our results suggest that different restrictions, such as anatomical constraints, behavior, and phylogenetic inertia, may be important for the studied species. [ABSTRACT FROM AUTHOR]

Urban environments are habitat mosaics, often with an abundance of exotic flora, and represent complex problems for foraging arboreal birds. In this study, we used compositional analysis to assess how Blue Tits Cyanistes caeruleus and Great Tits Parus major use heterogeneous urban habitat, with the aim of establishing whether breeding birds were selective in the habitat they used when foraging and how they responded to nonnative trees and shrubs. We also assessed whether they showed foraging preferences for certain plant taxa, such as oak Quercus, that are important to their breeding performance in native woodland. Additionally, we used mixed models to assess the impact of these different habitat types on breeding success (expressed as mean nestling mass). Blue Tits foraged significantly more in native than non-native deciduous trees during incubation and when feeding fledglings, and significantly more in deciduous than evergreen plants throughout the breeding season. Great Tits used deciduous trees more than expected by chance when feeding nestlings, and a positive relationship was found between the availability of deciduous trees and mean nestling mass. Overall, the breeding performance of both species was poor and highly variable. Positive relationships were found between mean nestling mass and the abundance of Quercus for Great Tits, but not for Blue Tits. Our study shows the importance of native vegetation in the complex habitat matrix found in urban environments. The capacity of some, but not all, species to locate and benefit from isolated patches of native trees suggests that species vary in their response to urbanization and this has implications for urban ecosystem function. [ABSTRACT FROM AUTHOR]

Summary: Although camera trapping has been shown to be a highly effective non‐invasive tool for wildlife monitoring, the technique has not yet been widely applied to studies of arboreal species. Despite the unique challenges that camera trapping in the canopy poses, its versatility and relatively non‐invasive nature, combined with recent technological improvements on the cameras themselves, make camera trapping a highly useful tool for arboreal research. We present data on the methodology and effectiveness of arboreal camera trapping during the first 6 months of a year‐long study in the Lower Urubamba Region of Peru investigating animal use of natural crossing points (i.e. branches) over a natural gas pipeline clearing. We placed Reconyx PC800 Hyperfire cameras in 25 crossing points of 13 distinct natural canopy ‘bridges’ at a mean height of 26·8 m. After 6 months of data collection, we logged 1522 photoevents, recording 20 mammal, 23 bird and four reptile species. An analysis of animal passing events in front of the cameras over time did not suggest any negative response to camera presence. While we found that cameras in the canopy are triggered more frequently by non‐target stimuli (e.g. leaves) than cameras on the ground, we demonstrated significantly reduced false triggering following leaf removal within 1·5 m of the camera. Our results suggest that arboreal camera trapping can provide robust documentation of a diversity of vertebrate species engaged in a variety of activities, and we provide recommendations for other researchers interested in using in this method. This is the most extensive arboreal camera trapping study to date in terms of the length of the study period, the number of cameras being used and the height of the cameras in the trees. Therefore, lessons provided from this experience can be used to improve the design of future arboreal camera trap studies. [ABSTRACT FROM AUTHOR]

We report the results of the first systematic assessment of global patterns and research priorities emerging in the field of rodent pest management. We carried out an extensive literature review targeted towards identifying the most relevant rodent pests, their impacts and the most common methods used to control them., We identified three disproportionally important pest species that are characterized by severe, generalist and geographically widespread impacts: the black rat Rattus rattus, the Norway rat Rattus norvegicus and the house mouse Mus musculus. Overall, only 7% of known rodent species may be considered pests. Scansorial (i.e. terrestrial and semi-arboreal) and fossorial species are generally important as pests, while aquatic and arboreal species have only specific impacts., Impacts of rodent pests on arable crops were studied most, followed by impacts on ecosystems. Studies on arable crops were typical in countries with low net income and health expenditure, while the opposite was observed for studies on ecosystems. Poisons were the most commonly used control method, followed by traps and habitat management. The need to control rodent species is expanding, especially to protect ecosystems and public health. Unlike in other fields of pest management (e.g. insect control), in rodent control we are approaching new problems with old solutions; control strategies and methods have not kept pace with emerging impacts., The need to control a rodent pest species is higher when it is non-native than within its original geographical range. The impact of a rodent species in its native range is a good predictor of the impact it may have in areas of introduction., Our review will contribute towards guiding researchers and stakeholders to focus research efforts and investments on a subset of species, and on new, less hazardous control techniques. [ABSTRACT FROM AUTHOR]

Tropical termites are physiologically adapted to a narrow range of climatic conditions, and as a result may be particularly impacted by global climate change. Because of their key roles as decomposers and ecosystem engineers, any climatic impact on termites could have serious ramifications for tropical ecosystems. The ability of termites to mediate their nest environment could allow them to cope with these changes., The temperature and RH in nests of the tropical termite Nasutitermes acajutlae were compared with ambient conditions on the island of St John, U.S. Virgin Islands, over a 5-year period using data loggers inserted into nest cartons., Nest conditions were found to be significantly warmer, more humid, and less variable than ambient conditions with respect to both temperature and RH., A comparison of dead nests, live non-reproductive nests, and live reproductive nests revealed that temperature mediation appears to be primarily the result of the presence of termites, with reproductive nests producing the highest temperatures, while high RH is maintained by the insulating effects of the nest material., Environmental variability across the years of this study had a significant influence on nest temperature and RH, suggesting that if tropical conditions become warmer and drier as predicted, N. acajutlae may have difficulty adapting over the long term. [ABSTRACT FROM AUTHOR]

Habitat loss and invasive predators increasingly threaten global biodiversity. Here we use a landscape-scale experimental approach to explore the individual and synergistic effects of logging and an invasive predator, the red fox Vulpes vulpes on two common native arboreal vertebrates (a predator and prey species) in south-eastern Australia. We used site occupancy methods to evaluate different models evaluating the effects of site specific forest logging disturbance, lethal fox baiting and forest structural elements for explaining variation in site occupancy of a large monitor lizard Varanus varius, and a marsupial prey, the common ringtail possum Pseudocheirus peregrinus across a complex forest landscape. Site occupancy of ringtail possum was influenced by habitat resources and the structural complexity of forest, which indirectly mediated predation risk. Presence of fox baiting had no direct effect on the ringtail site occupancy. In contrast, access to prey resources and fox baiting appeared to best explain site occupancy variation in monitor lizards across the landscape. While these species are affected primarily by separate disturbances, synergistic interactions between the processes may intensify their effects. Our results demonstrate that species susceptibility to disturbance processes are highly idiosyncratic. This approach makes efficient use of integrated modelling to aid conservation management at both local and landscape levels. [ABSTRACT FROM AUTHOR]

The use of the hand in food grasping is a shared characteristic of primates. However, the factors involved in the elaboration of this function remain unclear. Grasping hands may have evolved in an arboreal habitat with narrow branches. Interestingly, grasping may also have an association with different types of feeding such as insect predation, fruit and flower exploitation, or both. No study has tested the importance of substrate diameter and food properties on the use of the hand in food grasping. Yet, both of these parameters likely impose important selective pressures on the origin and evolution of manual grasping strategies in the context of food acquisition. Here, we quantified whether (1) substrate diameter (narrow, wide) and (2) food properties (static, slow moving, fast moving) influence food grasping in a small primate, M icrocebus murinus. Our results show that narrow substrates increase the use of hands in prey grasping. The mouth is preferentially used to grasp static food (banana), whereas the hands are preferred to grasp moving prey (mealworm and cricket) regardless of the substrate. Thus, the narrow branch niche may be an important selective pressure on the emergence of manual food grasping in primates, but predation likely also played a key role. [ABSTRACT FROM AUTHOR]