bluuebunny/crossref_metadata_2025 huggingface dataset:
Ideas and alternatives in American grand strategy, 2000–2004
Authors: Dueck Colin
Published: October 2004

American grand strategy has undergone repeated changes in recent years. This essay clarifies the nature of those changes and offers an explanation for them. US foreign policymakers have had four basic strategic alternatives: a strategy of disengagement; a strategy of balance of power; a strategy of primacy; and a strategy of liberal internationalism. The Bush administration experimented with two of these strategies, and initiated two major strategic adjustments after coming into power: the first, early in 2001, by moving from Clinton's liberal internationalist approach towards a strategy of realism; the second, after the terrorist attacks of 11 September 2001, by moving from a realist approach towards a strategy of American primacy. International structural pressures cannot explain why either of these changes occurred. The real explanation lies in the influence of distinctive policy ideas, as promoted by leading state officials. The irony of this twofold strategic adjustment is that the realists of the Bush administration have returned to many of the Wilsonian assumptions that characterised the Clinton years.
The United States and state-building in Iraq
Authors: Tripp Charles
Published: October 2004

RANDAmerica's Role in Nation-Building: from Germany to Iraq (Santa Monica, CA: RAND, 2003)

Imaging Iraq

On the back cover of this book there is a warm endorsement of its contents by none other than Paul Bremer, effectively the US Governor General of Iraq from May 2003 until June 2004. He claims to regard the book as ‘a marvellous “how to” manual for post conflict stabilization and reconstruction. I have kept a copy handy for ready consultation since my arrival in Baghdad.’ Events in Iraq during the past year would suggest either that he misplaced his copy of the book early in the occupation – or simply chucked it behind a sofa when he realised that it no longer told him what he wanted to know.
Logics of mind and international system: a journey with Robert Jervis
Authors: Balzacq Thierry , Jervis Robert
Published: October 2004

The following exchange builds upon, and reassesses, the intellectual trajectory of Robert Jervis since The Logic of Images. It is organised around three interrelated sections that, tentatively, squeeze out the gist of Jervis' contribution to IR during his three and half decades of remarkable scholarship. The purpose, however, is not to offer a comprehensive view of Jervis' work; instead I want to set signposts that will help us get smoothly into his ‘system of thought’ and substantiate the salience of his account. In the first section, we concentrate on issues of images and (mis)perceptions. Here, Jervis reasserts that political psychology, a crucial site of relevance of actors' behaviour, is perfectly amenable to a rigorous analysis, and should thus be granted a pivotal role in understanding the dynamics of world politics. Insights of political psychology, with their various implications, are taken up into the next section, the rationale of which is to dialogically sketch out the paradoxical ethos of deterrence theory. The third section, on complexity theory, brings forward the breadth of Jervis's reorientation, characterised by a systematic integration of various ideas that have been at the centre of his endeavour since the 1980s. We use contemporary world politics as a thread that connects the aforementioned segments of the discussion and thereby gives the journey its overall coherence.
Liberalism and empire: logics of order in the American unipolar age
Authors: Ikenberry G. John
Published: October 2004

The United States dominates the world as no state has. It emerged from the Cold War the world's only superpower, and no geopolitical or ideological contenders are in sight. Europe is drawn inward and Japan is stagnant. A half-century after their occupation, the United States still provides security and garrisons troops in Japan and Germany – the world's second and third largest economies. US military bases and carrier battle groups ring the world. Russia is in a quasi-formal security partnership with the United States, and China has accommodated itself to US dominance, at least for the moment. For the first time in the modern era, the world's most powerful state can operate on the global stage without the counterbalancing constraints of other great powers. We have entered the American unipolar age.
Control of flexible manipulators: A survey
Authors: Benosman M. , Le Vey G.
Published: October 2004

A survey of the field of control for flexible multi-link robots is presented. This research area has drawn great attention during the last two decades, and seems to be somewhat less “attractive” now, due to the many satisfactory results already obtained, but also because of the complex nature of the remaining open problems. Thus it seems that the time has come to try to deliver a sort of “state of the art” on this subject, although an exhaustive one is out of scope here, because of the great amount of publications. Instead, we survey the most salient progresses – in our opinion – approximately during the last decade, that are representative of the essential different ideas in the field. We proceed along with the exposition of material coming from about 119 included references. We do not pretend to deeply present each of the methods quoted hereafter; however, our goal is to briefly introduce most of the existing methods and to refer the interested reader to more detailed presentations for each scheme. To begin with, a now well-established classification of the flexible arms control goals is given. It is followed by a presentation of different control strategies, indicating in each case whether the approach deals with the one-link case, which can be successfully treated via linear models, or with the multi-link case which necessitates nonlinear, more complex, models.
Some possible issues for future research are given in conclusion.
Soccer robot path planning based on the artificial potential field
approach with simulated annealing
Authors: Zhang Pei-Yan , Lü Tian-Sheng , Song Li-Bo
Published: October 2004

The paper presents research on the APF approach for solving the GNRON and local minima problems. The repulsive potential function is modified in order to solve the GNRON problem. A simulated annealing algorithm integrated into the APF has solved the local minimum problem. The improved APF is applied to the path-planning problem of soccer robots. The simulated experiments show the validity of this approach.
Dynamic simulations of electromechanical robotic systems driven by DC motors
Authors: Kim Moojin , Moon Wonkyu , Bae Daesung , Park Ilhan
Published: October 2004

When modeling the dynamics of robotic systems containing electric motors, the force generated by the motor is generally considered only as an applied torque or force that is independent of mechanical state variables such as velocity. Due to the electromechanical coupling effects in the motors, this approach leads engineers working on a robotic system to designing faulty controllers. In this paper, we propose a dynamics analysis model in which DC motor dynamics are embedded into a mechanical dynamics model such that the electromechanical coupling effects are included in the overall model. A model for the DC motor is developed based on its equivalent circuit model and incorporated into the generalized recursive dynamics formula previously developed by our group. The resulting dynamic numerical simulation program provides an effective and realistic approach for analyzing the electromechanical dynamics of robotic systems driven by DC motors. The developed numerical simulation tool is evaluated by applying to an industrial robot and a flexible antenna system driven by DC motors for a satellite.
A peculiar flip-flop actuator for an in-pipe microrobot
Authors: Libersa C. , Arsicault M. , Gazeau J. P. , Lallemand J. P.
Published: October 2004

The work presented here concerns the design and manufacturing possibility of a polymodular autonomous microrobot moving like an earthworm. The study consists of the development of a new locomotion actuator based on shape memory alloys. This actuator is formed by a flexible frame forced in post-buckling by its assembly on a rigid skeleton cage. This mechanical structure, forming a knot in the microrobot chain, uses its two post-buckling equilibrium positions to achieve first the support and second the local lengthening enabling the movement of the microrobot. Initially, we present the technical solution designed for the locomotion actuator and the mechanical characterization of its malleable structure. Then, we present the instrumentation by educated SMA of a malleable structure and the capability of microrobot locomotion task in a vertical tube.
On the maximum dynamic stress search problem for robot manipulators
Authors: Khoukhi A. , Ghoul A.
Published: October 2004

This paper deals with the problem of the dynamic stress optimisation for manipulator robots. The maximum dynamic stress search is a challenging problem, insofar the dynamic stresses change in a very complex manner and they are strongly influenced by the payload, internal parameters of the robot, and instantaneous values of the articular variables (positions, velocities, and accelerations). This problem is solved using a hybrid simplex-genetic algorithm. This algorithm allows solving the dilemma of exploration vs. exploitation in the search space. A simulation study shows the greater performance of the proposed approach as compared to a classical approach of the configuration space inverse sweeping.
A stiffness analysis for a hybrid parallel-serial manipulator
Authors: Carbone Giuseppe , Ceccarelli Marco
Published: October 2004

In this paper a hybrid parallel-serial manipulator, named as CaHyMan (Cassino Hybrid Manipulator), is analyzed in term of stiffness characteristics as a specific example of a general procedure for analyzing stiffness of parallel-serial manipulators. A formulation is presented to deduce the stiffness matrix as a function of the most important stiffness and design parameters of the mechanical design. A formulation is proposed for a stiffness performance index by using the obtained stiffness matrix. A numerical investigation has been carried out on the effects of design parameters and fundamental results are discussed in the paper.
Emotion-based biped walking
Authors: Lim Hun-ok , Ishii Akinori , Takanishi Atsuo
Published: October 2004

This paper describes emotion-based walking for a biped humanoid robot. In this paper, three emotions, such as happiness, sadness and anger are considered. These emotions are expressed by the walking styles of the biped humanoid robot that are preset by the parameterization of its whole body motion. To keep its balance during the emotional expressions, the motion of the trunk is employed which is calculated by the compensatory motion control based on the motions of the head, arms and legs. We have constructed a biped humanoid robot, WABIAB-RII (WAseda BIpedal humANoid robot-Revised II), to explore the issue of the emotional walking motion for a smooth and natural communication. WABIAN-RII has forty-three mechanical degrees of freedom and four passive degrees of freedom. Its height is about 1.84 m and its total weight is 127 kg. Using WABIAN-RII, three emotion expressions are experimented by the biped walking, including the body motion, and evaluated.
Pattern and impact of hornbill seed dispersal at nest trees in a moist evergreen forest in Thailand
Authors: Kitamura Shumpei , Yumoto Takakazu , Poonswad Pilai , Noma Naohiko , Chuailua Phitaya , Plongmai Kamol , Maruhashi Tamaki , Suckasam Chumphon
Published: October 2004

Following the entire process of frugivore seed dispersal, from intake of seeds to seed deposition, is a difficult task. One alternative is to monitor areas of heavy seed rain deposited by animals. We quantified the number of seeds deposited by hornbills and followed the fates of these seedlings for 3 y to evaluate the effectiveness of hornbill seed dispersal at nest trees, on the basis of seedling survival. For 14 mo, fallen fruits and seeds were collected in traps established around four nest trees of each of two hornbill species (Aceros undulatus and Anthracoceros albirostris) and the seedlings were monitored in adjacent quadrats. Seedfall and seedlings of species represented in hornbill diets occurred at significantly higher densities in the traps/quadrats in front of nest cavities than in other traps/quadrats. Fewer seedling species and individuals germinated under nest trees than expected from the composition of the seedfall. Our results suggest that the quality of hornbill seed dispersal might be poor at nest trees due to the highly concentrated seedfall, which results in high seed and seedling mortality. Although seed deposition at nest trees is a useful guide to hornbill diet during the breeding season, it is clearly not of benefit to the plants involved. However, the pattern and consequences of hornbill seed dispersal at nest sites is likely very different from that during the non-breeding season.
Spatiotemporal patterns in indirect defence of a South-East Asian ant-plant support the optimal defence hypothesis
Authors: Heil Martin , Feil Daniel , Hilpert Andrea , Linsenmair K. Eduard
Published: October 2004

The optimal defence hypothesis predicts that plant parts characterized by a high value and/or a high risk of being attacked should exhibit the highest level of defence. We tested this hypothesis with Macaranga bancana ant-plants, which are protected efficiently by resident, mutualistic ants from herbivores, parasites and encroaching vegetation. Because cost-effective defence of the host by ants increases ant fitness, selection should act on ant behaviour to produce patterns of distribution of defence as predicted for direct chemical defence traits. Termites and pieces of tape were equally distributed over the uppermost ten leaves and over the leaf-bearing part of the stems (with termites mimicking a transient herbivore, while tape mimics a long-term stress caused by a climber or plant parasite). This arrangement allowed a separation of putative coevolutionary adaptations in the ants' behaviour from other potential sources of spatial patterns in ant defence, such as differences in herbivore pressure, in the vulnerability of different herbivores, or in direct plant defences. Ant activity dropped rapidly at termite baits, but remained high at tapes for at least 5 h, thereby demonstrating adaptive differential responses to the differences between the two stressors. Most importantly, ants preferentially defended young leaves and shoot parts. The temporal and spatial patterns of ant attention to exogenous stressors thus were clearly adaptive, varying with likely costs and benefits of defence as formulated in the optimal defence theory.
Foraging ecology of woodpeckers in lowland Malaysian rain forests
Authors: Styring Alison R. , Hussin Mohamed Zakaria bin
Published: October 2004

We investigated the foraging ecology of 13 species of woodpecker in logged and unlogged lowland rain forest at two forest reserves in West Malaysia (Pasoh Forest Reserve and Sungai Lalang Forest Reserve). The parameters perch diameter and microhabitat/substrate type explained more variation in the data than other parameters, and effectively divided the guild into two groups: (1) ‘conventional’ – species that excavated frequently, used relatively large perches, and foraged on snags and patches of dead wood, and (2) ‘novel’ – species that used smaller perches and microhabitats that are available in tropical forests on a year-round basis (e.g. external, arboreal ant/termite nests and bamboo). These novel resources may explain, in part, the maintenance of high woodpecker diversity in tropical rain forests.
Effects of logging on woodpeckers in a Malaysian rain forest: the relationship between resource availability and woodpecker abundance
Authors: Styring Alison R. , Hussin Mohamed Zakaria bin
Published: October 2004

We investigated the microhabitat preferences and relative abundances of 13 species of woodpecker in Sungai Lalang Forest Reserve, West Malaysia. The availability of suitable microhabitat corresponded strongly with woodpecker abundance, and snags were the most highly preferred foraging substrate across species and study sites. Large amounts of necromass, including snags, were present in 5-y-old logged and unlogged forest, but dead wood was in low abundance in 10-y-old logged forest. The absence or scarcity of large, snag-foraging woodpeckers from older logged stands suggests that this resource may remain in low abundance for a considerable time.
Epizoochorous dispersal by bats in French Guiana
Authors: Lobova Tatyana A. , Mori Scott A.
Published: October 2004

In neotropical forests many species of plant depend on animals for pollination and seed dispersal and it has been well documented that bats play an essential role in dispersal of many flowering plants (Gardner 1977). Bats are responsible for colonization of plants into forest gaps because they often disperse the seeds of plants adapted for growth in disturbed areas. Species of Cecropia, Piper, Solanum and Vismia are especially important pioneer plants, and bats play a critical role in the dispersal of these secondary woody species into both secondary and primary forests, and into the seed bank (de Foresta et al. 1984, Lobova et al. 2003).
Myrmecochory in the Zingiberaceae: seed removal of Globba franciscii and G. propinqua by ants (Hymenoptera – Formicidae) in rain forests on Borneo
Authors: Pfeiffer Martin , Nais Jamili , Linsenmair K. Eduard
Published: October 2004

The Old-World tropics encompass one of the floristically richest zones of the world and some of the hot spots of ant diversity. This results in a large variety of ecological interactions between both groups. One of them is the phenomenon of myrmecochory, seed dispersal by ants, which is also well known from temperate forests (Gorb & Gorb 2003, Ulbrich 1919), and which is most prominent in sclerophyll shrublands of Australia and southern Africa (Andersen 1988). Beattie (1983), who reviewed the distribution of ant-dispersed plants (at least 80 plant families worldwide) proposed that species richness and abundance of myrmecochores and diaspore-dispersing ants increases with decreasing latitude and thus predicted a greater variety of ant-dispersal systems in the tropics. However, up to now, few tropical myrmecochores have been described (Horvitz 1981, Horvitz & Schemske 1986), especially in the palaeotropics (Kaufmann et al. 2001). Here we report myrmecochory in two species of rain-forest herb of the Zingiberaceae, give the first evidence for seed dispersal by ants in this plant family and present a list of seed-dispersing ant species. An important benefit of myrmecochory is the dispersal distance of the ant-transported seeds (Andersen 1988), that has been found to be positively correlated with ant size (Gomez & Espadaler 1998a, Pudlo et al. 1980). In this study, we checked whether this correlation is also true for the conditions of the tropical rain forest, where Globba plants occur.
Short-term drought causes synchronous leaf shedding and flushing in a lowland mixed dipterocarp forest, Sarawak, Malaysia
Authors: Ichie Tomoaki , Hiromi Toru , Yoneda Reiji , Kamiya Koichi , Kohira Masao , Ninomiya Ikuo , Ogino Kazuhiko
Published: October 2004

Tropical rain forests are evergreen and experience a climate suitable for plant growth year round (Whitmore 1998). However, most tropical rain-forest trees display periodic shoot growth (Borchert 1991) and show synchronous leaf flushing at the community level (Itioka & Yamauti in press, Medway 1972, Ng 1981). Synchronous leaf flushing may have a great impact on animal population such as herbivores, because young leaves are suitable food resources for many herbivores (Aide 1988, 1992; Coley 1983, Itioka & Yamauti 2004, Lowman 1985).
General herbivore outbreak following an El Niño-related drought in a lowland Panamanian forest
Authors: Van Bael Sunshine A. , Aiello Annette , Valderrama Anayansi , Medianero Enrique , Samaniego Mirna , Wright S. Joseph
Published: October 2004

A severe outbreak of Lepidoptera followed the 1997–98 El Niño Southern Oscillation event, during which the climate in central Panama was unusually dry. The outbreak involved the larvae of at least 12 species of Lepidoptera and occurred at a seasonally dry, deciduous forest site, where extensive background data were available regarding climate, tree species and non-outbreak herbivory levels. Most Lepidoptera were associated with only one or two larval host plant species belonging to the same family, and the majority were monophagous during this study. During the outbreak, caterpillar densities for the major outbreak species averaged 1.6 larvae per young leaf and 0.18 larvae per leaf for leaves of all ages. For canopy trees and lianas, the mean level of leaf damage was 13.8%, ranging from 1–100%. Seven out of 20 tree species sustained most of the damage, with 21–37% of the leaf area consumed. Relative to non-outbreak years, damage levels increased by more than 250% during the outbreak. Single-species outbreaks were observed in other areas with a similar drought, but wetter forests in central Panama did not experience outbreaks during this period. Historically, fewer outbreaks have been reported from tropical forests than from temperate forests, however, similar El Niño-related outbreaks have occurred recently in several other locations throughout the tropics.
Habitat structure, wing morphology, and the vertical stratification of Malaysian fruit bats (Megachiroptera: Pteropodidae)
Authors: Hodgkison Robert , Balding Sharon T. , Zubaid Akbar , Kunz Thomas H.
Published: October 2004

This study investigated the vertical stratification of Old World fruit bats (Chiroptera: Pteropodidae) in relation to habitat structure and wing morphology, in a lowland Malaysian rain forest. In total, 352 fruit bats of eight species were captured within the subcanopy of the structurally complex old-growth forest during 72 306 m2 mist net hours of sampling. Fruit bat species that were grouped in relation to capture height were also grouped in relation to wing morphology – with those species predicted to have more manoeuvrable flight (i.e. lower wing-loadings and lower aspect-ratios) captured in increasingly cluttered airspaces. Thus, small differences in wing morphology are likely to be ecologically significant to the vertical stratification of bats. Hence, habitat heterogeneity may be a key factor promoting fruit bat species diversity in old-growth palaeotropical forests.
Leaf damage induces ant recruitment in the Amazonian ant-plant Hirtella myrmecophila
Authors: Romero Gustavo Q. , Izzo Thiago J.
Published: October 2004

Allomerus octoarticulatus is a plant-ant that colonizes domatia of the understorey tree Hirtella myrmecophila in the Central Amazon and forages for invertebrates, including leaf herbivores, on the host plant. We conducted manipulative experiments to study the ant's recruitment response to damaged leaves and leaf extracts of the host and to extracts of Protium hebetatum, a non-myrmecophytic sympatric tree species. Artificial damage to leaves of H. myrmecophila caused an increase in the number of recruits to the leaf. Ant response was stronger in young than in mature leaves. Recruitment was restricted to damaged leaves. No increment in recruitment rates was observed in undamaged, adjacent leaves. Different levels of leaf damage did not elicit differences in recruitment rates. Aqueous extract of leaves, placed on undamaged leaves of the host plant, also led to increased recruitment compared with water (control), and more ants were recruited to extracts from young than from mature and old leaves. Extracts of both H. myrmecophila and Protium hebetatum induced recruitment. We discuss the evolutionary importance of plant leaf components for maintenance of the ant-plant mutualism.
Resistance of a lowland rain forest to increasing drought intensity in Sabah, Borneo
Authors: Newbery D. M. , Lingenfelder M.
Published: October 2004

Occasional strong droughts are an important feature of the climatic environment of tropical rain forest in much of Borneo. This paper compares the response of a lowland dipterocarp forest at Danum, Sabah, in a period of low (LDI) and a period of high (HDI) drought intensity (1986–96, 9.98 y; 1996–99, 2.62 y). Mean annual drought intensity was two-fold higher in the HDI than LDI period (1997 v. 976 mm), and each period had one moderately strong main drought (viz. 1992, 1998). Mortality of ‘all’ trees ≥10 cm gbh (girth at breast height) and stem growth rates of ‘small’ trees 10–<50 cm gbh were measured in sixteen 0.16-ha subplots (half on ridge, half on lower slope sites) within two 4-ha plots. These 10–50-cm trees were composed largely of true understorey species. A new procedure was developed to correct for the effect of differences in length of census interval when comparing tree mortality rates. Mortality rates of small trees declined slightly but not significantly between the LDI and HDI periods (1.53 to 1.48% y−1): mortality of all trees showed a similar pattern. Relative growth rates declined significantly by 23% from LDI to HDI periods (11.1 to 8.6 mm m−1 y−1): for absolute growth rates the decrease was 28% (2.45 to 1.77 mm y−1). Neither mortality nor growth rates were significantly influenced by topography. For small trees, across subplots, absolute growth rate was positively correlated in the LDI period, but negatively correlated in the HDI period, with mortality rate. There was no consistent pattern in the responses among the 19 most abundant species (n≥50 trees) which included a proposed drought-tolerant guild. In terms of tree survival, the forest at Danum was resistant to increasing drought intensity, but showed decreased stem growth attributable to increasing water stress.
Relationships between alien plants and an alien bird species on Reunion Island
Authors: Mandon-Dalger Isabelle , Clergeau Philippe , Tassin Jacques , Rivière Jean-Noël , Gatti Sylvain
Published: October 2004

Many studies have shown that plant or bird invasions can be facilitated by native species, but few have demonstrated the possibility of a positive interaction between introduced species. We analysed the relationships between four invasive alien fleshy-fruited plants, Clidemia hirta, Rubus alceifolius, Lantana camara, Schinus terebinthifolius, and an invasive alien bird, the red-whiskered bulbul Pycnonotus jocosus introduced to Reunion Island (Indian Ocean). We compared the distribution of food items in the bulbul diet according to seasons and to abundance classes of this bird. Pycnonotus jocosus is mostly frugivorous and frequently eats the main alien plants (more than 80% frequency of food items). Sites with alien species, such as Clidemia hirta, providing fruits throughout the year supported more birds than sites providing fruits, such as Schinus terebinthifolius, seasonally. The birds facilitated seed germination by removing the pulp of fruit: the final per cent germination (FG) of cleaned seeds was higher than those within the fruit for three of the four plant species and in some cases passage through birds significantly increased FG (Schinus terebinthifolius) or Coefficient of Velocity (CV) (Lantana camara).
Soil seed bank and vegetation dynamics in Sahelian fallows; the impact of past cropping and current grazing treatments
Authors: Hérault Bruno , Hiernaux Pierre
Published: October 2004

The soil seed bank in a 5-y-old Sahelian fallow was studied through seed extraction and compared with germinations recorded either in controlled conditions, ex situ in a glasshouse, or in the field. The influence of phosphorus fertilizer and mulch application during the preceding crop period, and that of seasonal grazing regimes applied the last 2 y of fallowing, were assessed on the composition of the seed stock. Ctenium elegans, Fimbristylis hispidula, Merremia pinnata and Phyllanthus pentandrus accounted together for 75% of extracted seeds, 72% of ex situ, and 62% of in situ seedlings. Mulch treatment was correlated with the first axis of the canonical correspondence analyses performed on the seedling datasets. Mulch and phosphorus fertilizer treatments held similar responses, as they both favoured the seed bank of erect dicotyledons such as P. pentandrus and Cassia mimosoides. On the whole, the effects of grazing remained modest compared with the residual effects of past crop management practices. However, seedling densities increased as a result of dry-season grazing, while the soil seed bank decreased with wet-season grazing. Grazing also reduced the spatial heterogeneity of the seed bank rather than the overall number of species.
The effects of forest fragmentation and increased edge exposure on leaf litter accumulation
Authors: Feeley Kenneth J.
Published: October 2004

In forested ecosystems leaf litter is generally the primary pathway through which nutrients are cycled from the canopy to the forest floor (other pathways include throughfall, stemflow and animal faeces; Jordan 1985). Consequently, any disturbance that alters the quantity or quality of litter can have dramatic impacts on nutrient cycling and the availability of essential nutrients to plants (Vitousek 1984). Fragmentation of tropical forests has been demonstrated to cause several changes in both the biotic (Cosson et al. 1999, Laurance et al. 1998, Saunders et al. 1991) and abiotic environments (Camargo & Kapos 1995, Debinski & Holt 2000, Laurance 2002, Laurance et al. 2002) and thus may influence litter accumulation in the remnant patches (Carvalho & Vasconcelos 1999, Didham 1998, Laurance et al. 2002).
Influence of its associated ant species on the life history of the myrmecophyte Cordia nodosa in French Guiana
Authors: Dejean Alain , Quilichini Angélique , Delabie Jacques H. C. , Orivel Jérôme , Corbara Bruno , Gibernau Marc
Published: October 2004

Variation in the ant species associated with myrmecophytes (plants that provide their associated ants with nesting space, and sometimes with a complete diet) has been noted at both the regional and local levels, with plant distribution generally wider than that of the ants (Fonseca & Ganade 1996). This is the case for Cordia nodosa Lamark (Boraginaceae, subfamily Ehretioideae) whose most frequent associate ant species in Peru are Allomerus demararae (Wheeler) and Azteca spp. (Yu & Pierce 1998), while Azteca sp.1 and Allomerus octoarticulatus are the most frequent in Amazonian Brazil and French Guiana, respectively (Fowler 1993, Solano et al. 2003). Cordia nodosa plants are understorey treelets mostly less than 2 m tall, but taller individuals can be found. Their domatia are swollen, hollow stem nodes that form as the growing shoot tip invaginates through a subapical pore that then closes over when the domatium is mature (Yu 2001). So, plant-ants must reopen the chamber where the pore used to be, thus forming a kind of prostoma.
Relations between fruits and disperser assemblages in a Malagasy littoral forest: a community-level approach
Authors: Bollen An , Elsacker Linda Van , Ganzhorn Jörg U.
Published: October 2004

Interactions among fleshy fruits and frugivore assemblages are presented from a 1-y study in the littoral forest of Sainte Luce, south-eastern Madagascar. This community-level approach allowed us to determine food selection by all consumer species and to evaluate the role different frugivores play in seed dispersal and predation. For this, interactions between 136 consumed fruit species and 13 frugivorous species were studied. Fruit and seed size were the most important physical factors determining food selection of all consumer species. Nutritionally birds favoured and mammals avoided lipid-rich fruits. For Cheirogaleus spp., that go into torpor, there was a trend to select sugar-rich fruit pulp. However, for numerous fruit traits the consumer species had no clear feeding preferences and they seemed to be quite flexible, eating whatever was available. This might be related to unpredictable fruit availability and low fruit productivity in the littoral forest, which may also partially explain the low number of frugivores present. Nevertheless frugivores have different impacts on seed dispersal. Eulemur fulvus collaris is particularly important for the dispersal of large-seeded species, while frugivorous birds and flying foxes ensure plant regeneration between and outside forest fragments. In terms of conservation, heterogeneous seed transport is particularly important for this severely degraded littoral forest.
Water input from fog drip in the tropical seasonal rain forest of Xishuangbanna, South-West China
Authors: Liu Wenjie , Meng Fan-Rui , Zhang Yiping , Liu Yuhong , Li Hongmei
Published: October 2004

Fog drip and related microclimatic factors were measured between January 1999 and December 2002 at a tropical seasonal rain forest in Xishuangbanna, South-West China. During the study period, the annual average fog drip was 89.4±13.5 mm (mean±1 SD). Fog drip contributes an estimated 5% of the annual rainfall, with 86% of the fog drip occurring in the dry season (November–April). Annual fog drip was negatively correlated with annual rainfall. Monthly variation in fog drip was also negatively correlated with monthly rainfall. Average daily fog drip was 0.38±0.27 mm d−1 for all days on which fog drip occurred. Daily fog drip was negatively correlated with minimum air temperature and positively correlated with mean above-canopy wind speed. The results indicate that fog drip is an important additional input of water to this seasonal rain forest during the dry season.
Jacky-Kalingaloonga: Aboriginality, Audience Reception and Charles Reade's It is Never Too Late To Mend (1865)
Authors: HENDERSON IAN
Published: October 2004

This article examines the representation of Aboriginality in Charles Reade's It is Never Too Late to Mend (1865). It does so by imagining the character of Jacky-Kalingaloonga in performance, specifically in performance by Stanislaus Calhaem – by a white actor in black-face – on the opening night of the melodrama's first London production. Bringing Calhaem back on stage in the mind's eye turns on recovering historic modes of reception, on reconstructing how audience members participated in bringing Jacky-Kalingaloonga ‘to life’. This problematizes readings of the mid-Victorian construction of Aboriginality which presume ‘fact’ claims such as Reade made for Jacky-Kalingaloonga were straightforwardly accepted by Victorian audiences as grounds on which to interpret the character as an authentic ‘anthropological’ specimen. Any promotion of this outcome instead became part of a play between the anthropological and the theatrical which Victorian audiences were expected to negotiate, incorporating that negotiation into an imperialist gesture effected in the process of performance on stage and in the auditorium.
From Orientalist to Postcolonial Representations: A Critique of Indian Theatre Historiography from 1827 to the Present
Authors: SOLOMON RAKESH H.
Published: October 2004

This essay offers a comparative critique of all major Indian theatre histories written during the modern era. It reveals three distinct representations of Indian theatre and argues that each was a manifestation of a discrete historiographic approach, shaped by its particular historical and cultural moment. Theatre histories of the Orientalist period offer a narrow and elitist construction of Indian theatre as synonymous with a single defunct genre, the ancient Sanskrit theatre. Histories of the high nationalist phase make a token acknowledgement of the Sanskrit and traditional genres but define Indian theatre as comprising primarily of the modern genre. Postcolonial histories construct a democratic and comprehensive Indian theatre – embracing the Sanskrit, traditional, and modern genre – but with an unpersuasively high significance assigned to the modern genre's post-Independence phase. Such different representations of Indian theatre show how theatre historiography in the modern period, like theatre historiography in any era, regularly refashioned itself under the pressure of changing historical, political, and cultural conditions.
Recasting the National Motherhood: Transactions of Western Feminisms in Korean Theatre
Authors: SHIM JUNG-SOON
Published: October 2004

The image of the National Motherhood is the potent cultural code for Koreans. The word ‘Feminism’ in the Korean context is identified as a system of ideas originating from the West. What happens when these two disparate cultural/historical impulses meet at the intersection of modern Korean theatre? This study examines the cultural transfer of Western feminisms and feminist plays in the Korean theatre from the 1920s, when Ibsen's play A Doll's House was first introduced to Korea, to the present. More specifically, it analyses six Western feminist plays such as Nell Dunn's Steaming and Marsha Norman's 'Night, Mother, by focusing on how the Korean women's movement and modern Korean drama movement intersect with each other in terms of historical and cultural background; how these two historical impulses interact with Western feminist plays in terms of the intentions and reception of such plays in the Korean theatre arena, and how the image of the National Motherhood, the potent cultural code for Koreans, intervenes in this process.
Is the distribution of the arid‐occurring otomyine rodents of southern Africa related to physiological adaptation or refuge type?
Authors: Jackson T. P. , Bennett N. C. , Spinks A. C.
Published: October 2004

Aspects of the physiology of the arid‐occurring otomyine rodents of southern Africa (Parotomys brantsii, Parotomys littledalei and Otomys unisulcatus) were examined, including: (1) renal function; (2) thermal physiology. Parotomys littledalei exhibited a maximum predicted urine‐concentrating ability similar to other arid‐occurring rodents. Maximum concentrating abilities were moderate for O. unisulcatus and low for P. brantsii. The extension of P. littledalei into the driest regions, in which it occurs allopatrically, suggests the importance of renal function in determining the distributional limits of these species. The thermophysiology of these otomyine species demonstrated a mixed ability to cope with aridity. Typical of arid‐occurring diurnal rodents, all became hyperthermic at high ambient temperatures. However, none exhibited several additional thermophysiological characteristics common to arid‐occurring rodents. Thus, resting metabolic rate was not lower than expected for body size, while lower critical temperatures were relatively low and the thermal neutral zone was broad. Nevertheless, the upper limit of thermoneutrality of P. littledalei was lower than that of P. brantsii or O. unisulcatus. The failure of P. littledalei to occur in hotter areas, in which P. brantsii occurs, seems to be related to its thermal physiology. Whereas renal function or thermophysiology may influence the arid extension of P. brantsii and P. littledalei, the high vulnerability of its refuges to fire damage may limit the distribution of O. unisulcatus. Reviewing the thermophysiology of the Otomyinae from more mesic habitats, we argue that their thermophysiology is more closely related to refuge type than aridity. Compared to the apparently specialized physiological mechanisms used by omnivorous or granivorous desert rodents, our study suggests behavioural adaptations such as refuge type and food selection are more important to the survival of these herbivorous desert rodents.
A gastrointestinal role for the amphibian ‘diaphragm’ of Xenopus laevis
Authors: Pickering Mark , Campion Deirdre , Jones James F. X.
Published: October 2004

The ‘diaphragm’ of Xenopus laevis has close anatomical relations to the lower end of the oesophagus. In mammals, the crural diaphragm acts as a pinch valve at the gastro‐oesophageal junction and is an important component of the gastro‐oesophageal reflux barrier. The present study analysed the effect of amphibian ‘diaphragm’ contraction on oesophageal pressure using a superfused in situ oesophago‐diaphragmatic preparation of large female Xenopus. Three‐dimensional reconstruction of the oesophageal pressure profile was performed using four‐port oesophageal infusion manometry. Bilateral electrical stimulation of the nerves supplying the ‘diaphragm’ of Xenopus increased the pressure volume vector of 5 mm of oesophagus (centred around the insertions of the diaphragm) from 20.4 ± 16 to 553.6 ± 232 mm · mmHg2 (mean ± SD). This was a statistically significant increase and statistically significantly higher than that evoked by electrical stimulation of both vagi (28.1 ± 30.7 mm·mmHg2). The amphibian ‘diaphragm’ seems to be functionally similar to the mammalian crural diaphragm. By analogy, we suggest that the original role of the diaphragm was not respiratory but gastrointestinal.
Sexual dimorphism in head shape and diet in the cottonmouth snake (Agkistrodon piscivorus)
Authors: Vincent Shawn E. , Herrel Anthony , Irschick Duncan J.
Published: October 2004

Sexual dimorphism is a common phenomenon among animals. The usual cause cited for sexual dimorphism in animals is sexual selection acting through female choice or male–male combat. Natural selection acting to reduce resource competition between the sexes, however, is an important alternative evolutionary scenario, but this possibility has received little empirical study. Here this issue is addressed by examining the relationships among body size, head shape and the functional aspects of diet in the adult male and female cottonmouth snake Agkistrodon piscivorus. In this species, males are larger in overall body and head size. Whereas an analysis of gross head measurements (simple linear head dimensions) shows little dimorphism in head shape, a more detailed analysis of head shape (using digital images of the snakes’ heads) revealed some subtle, yet functionally significant, differences in head shape between adult male and female cottonmouths. Specifically, male cottonmouths have longer quadrate bones, and have greater lateral surface areas than females. Male cottonmouths also consumed relatively taller prey (prey size relative to snake body size) than conspecific females, and the sexes consumed significantly different proportions of prey. Because the size of the quadrate bone is a strong determinant of maximum gape in snakes, we suggest that the observed shape differences may reflect functional differences in maximum gape between similarly sized male and female cottonmouths. In turn, such differences in maximum gape width may explain why males consume taller prey than similarly sized females.
The influence of body condition and prey availability on female breeding success in the smooth snake (Coronella austriaca Laurenti)
Authors: Reading C. J.
Published: October 2004

A study of individually marked smooth snakes Coronella austriaca was carried out in Wareham Forest, southern England between 1992 and 2001. On average, approximately one‐third of potential breeding females reproduced each year and within this group, the proportion breeding was positively correlated with snout–vent length (SVL). Successful breeders had a higher than average body condition at the start of the breeding year compared with unsuccessful breeders. The density of gravid females was positively correlated with prey density in the breeding year but not in the year preceding it. No significant relationships were found between the density of non‐breeding females and prey density in either the breeding year or the preceding year. Although most breeding females did not produce young in consecutive years, a small proportion did. There was a weak positive relationship between clutch size and female SVL. This study suggests that the potential for female smooth snakes to breed is provided by stored energy reserves but that this potential is regulated by prey availability in the breeding year.
Eye size and behaviour of day‐ and night‐flying leafcutting ant alates
Authors: Moser John C. , Reeve John D. , Bento José Maurício S. , Della Lucia Terezínha M. C. , Cameron R. Scott , Heck Natalie M.
Published: October 2004

The morphology of insect eyes often seems to be shaped by evolution to match their behaviour and lifestyle. Here the relationship between the nuptial flight behaviour of 10 Atta species (Hymenoptera: Formicidae) and the eye size of male and female alates, including the compound eyes, ommatidia facets, and ocelli were examined. These species can be divided into two distinct groups by nuptial flight behaviour: those that initiate the nuptial flight during the day and those that initiate it at night. The most striking difference between day‐ vs night‐flying alates was in ocellus area, which was almost 50% larger in night‐flying species. Night‐flying species also had significantly larger ommatidia facets than day‐flying species. A scaling relationship was also found between compound eye area, facet diameter, and ocellus area vs overall body size. Detailed observations are also presented on the nuptial flight behaviour of a night‐ vs day‐flying species, A. texana and A. sexdens, respectively. The pattern in A. texana is for a single large and precisely timed nuptial flight before dawn, while flights of A. sexdens last for several hours, beginning at midday. Further observations suggest that the timing of the nuptial flight in A. texana is easily disrupted by light pollution.
Correlates of sexual dimorphism for dry weight and development time in five species of Drosophila
Authors: Bharathi N. Sharmila , Prasad N. G. , Shakarad Mallikarjun , Joshi Amitabh
Published: October 2004

Pre‐adult development time, dry weight at eclosion, and daily fecundity over the first 10 days of adult life were measured in five species of Drosophila from the melanogaster and immigrans species groups. Overall, the three species of the melanogaster group (D. melanogaster, D. ananassae, D. malerkotliana) developed faster, were lighter at eclosion, and produced more eggs per unit weight at eclosion than the two species of the immigrans group (D. n. nasuta, D. sulfurigaster neonasuta). The degree of sexual dimorphism in dry weight was greater than that in development time, but did not vary significantly among species, and was not correlated with fecundity, contrary to expectations that sexual selection for increased fecundity drives sexual size dimorphism in Drosophila. The degree of dimorphism in development time was significantly correlated with dry weight and fecundity, with lighter species tending to be more dimorphic for development time as well as more fecund, both in absolute terms and in terms of fecundity per unit weight. The results suggest that our understanding of the evolutionary forces maintaining sexual size dimorphism in Drosophila will probably benefit from more detailed studies on the correlates of sexual dimorphism within and among Drosophila species, and on the shape of reaction norms for the degree of sexual dimorphism across different levels of ecologically relevant environmental variables.