Major Feeding Guilds Research Articles

Feeding guild structure of birds at Keshopur Chhamb wetland, Gurdaspur

To achieve a comprehensive understanding of avian feeding guild structure the present study was conducted at Keshopur wetland Ramsar site, district Gurdaspur, Punjab, India. A total of 121 species of birds belonging to 19 orders and 47 families were observed. Direct observation techniques and focal sampling methods were used to study their foraging behaviour. Seven major feeding guilds ie., carnivorous, insectivorous, omnivorous, granivorous, herbivorous, frugivorous and nectarivorous were found. Maximum number of species were of carnivorous guild (28%) followed by insectivorous (21%). Cattle egret and red-wattled lapwing, members of carnivorous guild were observed to feed on insects also, hence placed in multiple guilds. Northern shoveler, eurasian coots and purple moorhen were seen foraging in association with each other. The large number of insectivorous birds depicts the presence of rich number of insects. The presence of birds belonging to seven foraging guilds highlight the significance of Keshopur wetland in providing a rich feeding ground to both migratory as well as resident birds.

Characterization of fish community structure and an estuarine fish community index for temporarily closed estuaries (TCEs) from India's south-western coast.

We present for the first time, data on fish assemblage structure for ten temporarily closed estuaries (TCEs) along the south-western coast of India. Fish community structure differed significantly between TCEs based on species presence/absence, estuarine use and feeding mode. Marine migrant and freshwater stragglers dominated the 'fish guilds', while piscivores and zoobenthivores were the major feeding guilds, in all estuaries. We used the Estuarine Fish Community Index (EFCI) and a Combined Anthropogenic Pressure Index (CPI) to determine the ecological quality of TCEs. The application of functional guilds and EFCI successfully represented the use of TCEs by fish communities, and also the functional similarities existing between fish assemblages of these estuaries, despite considerable taxonomic, physical and chemical differences. EFCI indicated that the ecological health of TCEs in south-western India ranges from 'poor' to 'good'. We also established a significant relationship between CPI, EFCI and ecological quality in various TCEs using the Generalized Linear Model (GLM).

Synchronous biological feedbacks in parrotfishes associated with pantropical coral bleaching.

Biological feedbacks generated through patterns of disturbance are vital for sustaining ecosystem states. Recent ocean warming and thermal anomalies have caused pantropical episodes of coral bleaching, which has led to widespread coral mortality and a range of subsequent effects on coral reef communities. Although the response of many reef-associated fishes to major disturbance events on coral reefs is negative (e.g., reduced abundance and condition), parrotfishes show strong feedbacks after disturbance to living reef structure manifesting as increases in abundance. However, the mechanisms underlying this response are poorly understood. Using biochronological reconstructions of annual otolith (ear stone) growth from two ocean basins, we tested whether parrotfish growth was enhanced following bleaching-related coral mortality, thus providing an organismal mechanism for demographic changes in populations. Both major feeding guilds of parrotfishes (scrapers and excavators) exhibited enhanced growth of individuals after bleaching that was decoupled from expected thermal performance, a pattern that was not evident in other reef fish taxa from the same environment. These results provide evidence for a more nuanced ecological feedback system-one where disturbance plays a key role in mediating parrotfish-benthos interactions. By influencing the biology of assemblages, disturbance can thereby stimulate change in parrotfish grazing intensity and ultimately reef geomorphology over time. This feedback cycle operated historically at within-reef scales; however, our results demonstrate that the scale, magnitude, and severity of recent thermal events are entraining the biological responses of disparate communities to respond in synchrony. This may fundamentally alter feedbacks in the relationships between parrotfishes and reef systems.

Conus Envenomation of Humans: In Fact and Fiction.

Prominent hallmarks of the widely distributed, mainly tropical marine snail genus Conus are: (1) its unusually high species diversity; it is the largest genus of animals in the sea, with more than 800 recognized species; and (2) its specialized feeding behavior of overcoming prey by injection with potent neurotoxic, paralytic venoms, and swallowing the victim whole. Including the first report of a human fatality from a Conus sting nearly 350 years ago, at least 141 human envenomations have been recorded, of which 36 were fatal. Most Conus species are quite specialized predators that can be classified in one of three major feeding guilds: they prey exclusively or nearly so on worms, primarily polychaete annelids, other gastropods, sometimes including other Conus species, or fishes. These differences are shown to relate to the severity of human envenomations, with the danger increasing generally in the order listed above and a strong likelihood that all of the known human fatalities may be attributable solely to the single piscivorous species C. geographus.

Body size-trophic position relationships among fishes of the lower Mekong basin.

Body size is frequently claimed to be a major determinant of animal trophic interactions, yet few studies have explored relationships between body size and trophic interactions in rivers, especially within the tropics. We examined relationships between body size and trophic position (TP) within fish assemblages in four lowland rivers of the Lower Mekong Basin in Cambodia. Stable isotope analysis (based on δ15N) was used to estimate TP of common fish species in each river, and species were classified according to occupation of benthic versus pelagic habitats and major feeding guilds. Regression analysis yielded strong correlations between body size and TP among fishes from the Sesan and Sreprok rivers, but not those from the Mekong and Sekong rivers. The Mekong fish assemblage had higher average TP compared with those of other rivers. The relationship between body size and TP was positive and significantly correlated for piscivores and omnivores, but not for detritivores and insectivores. The body size–TP relationship did not differ between pelagic and benthic fishes. Body size significantly predicted TP within the orders Siluriformes and Perciformes, but not for Cypriniformes, the most species-rich and ecologically diverse order in the Lower Mekong River. We conclude that for species-rich, tropical fish assemblages with many detritivores and invertivores, body size would not be an appropriate surrogate for TP in food web models and other ecological applications.

The parrotfish–coral relationship: refuting the ubiquity of a prevailing paradigm

It has become almost paradigmatic in the coral reef literature that fishing-induced reductions of parrotfish abundance cause benthic phase shifts from coral to macroalgal dominance. This study examined the alternatives of top-down control of the benthos by parrotfish density and bottom-up control of parrotfish density by the benthos at four Philippine islands in a long-term (7.5–30 years) “natural experiment”. No-take marine reserves (NTMRs) demonstrated that fishing reduced parrotfish density significantly at two islands (Sumilon, Mantigue), but not significantly at two other islands (Apo, Selinog). There was no evidence that cover of hard coral decreased, nor macroalgal cover increased, in fished areas relative to NTMRs, no evidence that parrotfish density affected hard coral cover significantly, and thus no evidence of top-down, fishing-induced benthic phase shifts at all four islands. There was, however, compelling evidence that benthos (cover of dead substrata and hard coral) exerted strong bottom-up control on parrotfish density. This bottom-up control was demonstrated most clearly by major environmental disturbances (e.g. typhoons, coral bleaching) that changed benthic habitat and, subsequently, parrotfish density. As hard coral cover declined (and cover of dead substratum increased), parrotfish density increased and vice versa. This response occurred in both major parrotfish feeding guilds (scrapers and excavators). This long-term study on heavily fished coral reefs suggests that the benthos drives the parrotfish, not the other way around. The paradigm of fishing-induced benthic phase shifts may not apply to all coral reefs at all times. Multiple drivers of benthic change on coral reefs should always be considered.

Status of wetland birds of Chhilchhila Wildlife Sanctuary, Haryana, India

The Chhilchhila Wildlife Sanctuary (76036-76046 E and 29052-30000 N), situated in Kurukshetra District of Haryana provides an important wintering ground for a diverse range of wetland birds. This study was carried out from April 2009 to March 2012 to document the diversity of wetland birds. Altogether 57 species of wetland birds belonging to 37 genera and 16 families were recorded from the study area. Family Anatidae dominated the wetland bird community with 13 species. Among recorded species, 33 were winter migrants, two summer migrants and 22 were resident species. The winter migratory birds did not arrive at this wetland in one lot and at one time. Instead, they displayed a definite pattern specific to species for arrival and departure. They appeared at the wetland during mid-October and stayed up to early April. The composition of birds in major feeding guilds in the study area showed that the insectivore guild was the most common with 35.09% species, followed by carnivore (29.82%), omnivore (19.30%), herbivore (10.53%) and piscivore (5.26%). Among the birds recorded in this study area, Darter (Anhinga melanogaster) and Painted Stork (Mycterialeucocephala) were Near Threatened species. Comb Duck (Sarkidiornismelanotos), listed in Appendix II of CITES, was also spotted in the sanctuary. The spotting of these threatened bird species highlights the importance of Chhilchhila Wildlife Sanctuary as a significant wetland bird habitat in Haryana. However, anthropogenic activities like fire wood collection, livestock grazing, cutting of emergent and fringe vegetation and improper management of the wetland are major threats to the ecology of this landscape.

Rapid Assessment and Feeding Guilds of Birds in Selected Rubber and Oil Palm Plantations in North Cotabato

The degradation of tropical rainforests in Mindanao has augmented the interest in the potential value of commercial plantations for the conservation of biodiversity. However, it is not yet apparent how this type of land use affects forest bird fauna since there were no studies conducted yet to document birds in commercial plantations, particularly in North Cotabato. Hence, this study was done to determine occurrence of birds in Carumba Oil Palm Plantation (COPP) and Platinum Rubber Plantation (PRP) in North Cotabato. A combination of mist netting and transect walk technique had recorded 30 birds species belonging to 6 orders, 19 families and 26 genera. Passeriformes was the most represented order having 20 species, six of which were country endemics and two were Mindanao faunal region endemics. Noteworthy was the presence of one threatened species ( Alcedo argentata ) from PRP with a vulnerable conservation status. Results indicate that oil and rubber agro-forestry systems contribute to conservation efforts by serving as habitats to endemic bird species. In addition, major feeding guilds of birds were also determined. Insectivorous species predominated in both areas. This high number of insectivorous species delivers a natural pest control service in the plantations which is beneficial to farmers and owners. Keywords - bird fauna, endemism, feeding guilds, rubber plantation, oil palm plantation, North Cotabato

Non-indigenous species in Mediterranean fish assemblages: Contrasting feeding guilds of Posidonia oceanica meadows and sandy habitats

Quantitative sampling in combination with classification of fish species into six major feeding guilds revealed the position and contribution of non-indigenous species (NIS) in the food web of Posidonia oceanica and sandy habitats in an area of the eastern Mediterranean. In P. oceanica beds and on sandy bottoms 10 and five species, respectively, were non-indigenous fish of Indo-Pacific origin. The proportional contribution of NIS individuals on P. oceanica beds was lower than that of sandy bottoms (12.7 vs. 20.4%) a pattern that also followed for biomass (13.6 vs. 23.4%), indicating that low diverse systems may be more liable to introductions than species-rich communities. The two habitats had similar fish feeding guilds, but the biomass contribution from NIS varied within each guild, indicating different degrees of impact on the available resources. This study showed that only few non-indigenous fish species contributed to the differences in biomass between habitats. No support could be found in postulating that taxonomic affiliation could predict invasion success. Size was considered highly important due to habitat shift of species with increased size. Two of the aspects considered in this study, the chance of establishing vs. the chance of being very dominant will depend upon competitive abilities strongly coupled to size and grounds for habitat shift. However, success of establishment will also depend on appropriate food resources in the recipient community as well as competitive abilities and level of competition in the food web within habitats.

Economic impacts of non-native forest insects in the continental United States.

Reliable estimates of the impacts and costs of biological invasions are critical to developing credible management, trade and regulatory policies. Worldwide, forests and urban trees provide important ecosystem services as well as economic and social benefits, but are threatened by non-native insects. More than 450 non-native forest insects are established in the United States but estimates of broad-scale economic impacts associated with these species are largely unavailable. We developed a novel modeling approach that maximizes the use of available data, accounts for multiple sources of uncertainty, and provides cost estimates for three major feeding guilds of non-native forest insects. For each guild, we calculated the economic damages for five cost categories and we estimated the probability of future introductions of damaging pests. We found that costs are largely borne by homeowners and municipal governments. Wood- and phloem-boring insects are anticipated to cause the largest economic impacts by annually inducing nearly $1.7 billion in local government expenditures and approximately $830 million in lost residential property values. Given observations of new species, there is a 32% chance that another highly destructive borer species will invade the U.S. in the next 10 years. Our damage estimates provide a crucial but previously missing component of cost-benefit analyses to evaluate policies and management options intended to reduce species introductions. The modeling approach we developed is highly flexible and could be similarly employed to estimate damages in other countries or natural resource sectors.

Feeding habits of demersal fish in Icelandic waters: a multivariate approach

AbstractStomach data were examined to assess the key factors that determine diet composition in some of the most important demersal fish species in Icelandic waters and to identify major feeding guilds. The data were collected during the groundfish surveys conducted by the Marine Research Institute in 1992. The factors examined included geographic position, depth, season, and fish size. Data were analysed using multivariate methods: canonical correspondence analysis (CCA), non-metric multi-dimensional scaling (NMDS), and hierarchical clustering. For the CCA, important explanatory variables for the observed feeding patterns were found using forward stepwise selection. Fish size was the most important explanatory variable for most species, reflecting distinct ontogenetic shifts in diets. A large variation in diet composition was observed, and the CCA model explained 6–16% of the total variation. The spatial and seasonal variability in diets reflected, in general, patterns of prey availability. Among the main predators, the two major feeding guilds were (i) species preying mainly on echinoderms, supplemented with fish and other benthic invertebrates, and (ii) species preying mainly on crustaceans and fish.

Interannual changes in folivory and bird insectivory along a natural productivity gradient in northern Patagonian forests

Trophic regulation models suggest that the magnitude of herbivory and predation (top‐down forces) should vary predictably with habitat productivity. Theory also indicates that temporal abiotic variation and within‐trophic level heterogeneity both affect trophic dynamics, but few studies addressed how these factors interact over broad‐scale environmental gradients. Here we document herbivory from leaf‐feeding insects along a natural rainfall/productivity gradient in Nothofagus pumilio forests of northern Patagonia, Argentina, and evaluate the impact of insectivorous birds on foliar damage experienced by tree saplings at each end of the gradient. The study ran over three years (1997–2000) comprising a severe drought (1998–1999), which allowed us to test how climatic events alter top‐down forces. Foliar damage tended to increase towards the xeric, least productive forests. However, we found a predictable change of insect guild prevalence across the forest gradient. Leaf miners accounted for the greater damage recorded in xeric sites, whereas leaf chewers dominated in the more humid and productive forests. Interannual folivory patterns depended strongly on the feeding guild and forest site. Whereas leaf‐miner damage decreased during the drought in xeric sites, chewer damage increased after the drought in the wettest site. Excluding birds did not affect leaf damage from miners, but generally increased chewer herbivory on hydric and xeric forest saplings. Indirect effects elicited by bird exclusion became most significant after the drought, when total folivory levels were higher. Thus, interannual abiotic heterogeneity markedly influenced the amount of folivory and strength of top‐down control observed across the forest gradient. Moreover, our results suggest that spatial turnovers between major feeding guilds may need be considered to predict the dynamics of insect herbivory along environmental gradients.

Fish feeding guilds in shallow rocky and soft bottom areas on the Swedish west coast

Multivariate analyses of the diet relationships within fish assemblages resulted in the recognition of five major feeding guilds in shallow (0‐9 m) rocky‐ and soft‐bottom habitats on the Swedish west coast. The two habitats had similar guilds that could be broadly described as piscivores, decapod feeders, copepod feeders and amphipod and mollusc feeders. The last guild on the rocky bottom was more strictly one of amphipod feeders, whereas the last guild on soft bottoms consisted of infauna feeders (mainly polychaetes and bivalves). A comparison of the diet of the entire fish assemblages showed that amphipods and gastropods were more prevalent as prey taxa on rocky bottoms, whereas bivalves and teleosts were more common on soft bottoms. A large proportion (12 out of 27 species) of the fish species investigated was found in both habitats. These fish species generally seemed to rely on the same major prey groups in the two habitats, but also included prey taxa characteristic for the habitat in which they resided. Sea trout Salmo trutta, mackerel Scombrus scombrus, saithe Pollachius virens, whiting Merlangius merlangus and cod Gadus morhua were found to be the major piscivores in both the investigated habitats. Herring Clupea harengus and members of the family gobiidae were the most prevalent prey species for piscivores within the rocky‐ as well as the soft‐bottom fish assemblage. A comparison of feeding modes suggested that the fish assemblage on rocky bottoms predominantly (60% of the food items) relied on food found in vegetation. On soft bottoms, the average distribution of food categories among fish species was 44% benthic, 35% pelagic and 21% vegetation‐associated food items.

Observations on the Feeding Ecology of Estuarine Nematodes

Observations on living estuarine nematodes show that previous feeding type classifications do not accurately represent the trophic structure of an intertidal mudflat in the Westerschelde Estuary (Netherlands). A new scheme with six major nematode feeding guilds is proposed: (1) microvores; (2) ciliate feeders; and (3) deposit feeders sensu stricto are all nematodes without a distinct buccal armature. In the first two groups bacteria and protozoa, respectively are the major particulate food sources, while other items are included in the diet of the third. The three other categories are recognized among the nematodes with a buccal armature: (4) epigrowth feeders; (5) facultative predators; and (6) predators. Diatoms and other microalgae are an important particulate food for many epigrowth feeders. The importance of bacteria as a food source for these nematodes remains poorly documented. A strictly or mainly predatory behaviour has been described for only few species from the study area. Several nematodes, however, are facultative predators. The predatory strategy of Calyptronema maxweberi, as described in this paper, suggests the use of a paralysing or lethal secretion in prey capture, which, to our knowledge, is the first report for aquatic nematodes. Furthermore, the importance of sources other than particulate food in free-living aquatic nematodes is stressed. Our observations show that many aquatic nematodes are in fact opportunistic feeders, which may change feeding strategies in response to available food.

Roles of oxygen and the intestinal microflora in the metabolism of lignin-derived phenylpropanoids and other monoaromatic compounds by termites

Prompted by our limited understanding of the degradation of lignin and lignin-derived aromatic metabolites in termites, we studied the metabolism of monoaromatic model compounds by termites and their gut microflora. Feeding trials performed with [ring-U-(sup14)C]benzoic acid and [ring-U-(sup14)C]cinnamic acid revealed the general ability of termites of the major feeding guilds (wood and soil feeders and fungus cultivators) to mineralize the aromatic nucleus. Up to 70% of the radioactive label was released as (sup14)CO(inf2); the remainder was more or less equally distributed among termite bodies, gut contents, and feces. Gut homogenates of the wood-feeding termites Nasutitermes lujae (Wasmann) and Reticulitermes flavipes (Kollar) mineralized ring-labeled benzoic or cinnamic acid only if oxygen was present. In the absence of oxygen, benzoate was not attacked, and cinnamate was only reduced to phenylpropionate. Similar results were obtained with other, nonlabeled lignin-related phenylpropanoids (ferulic, 3,4-dihydroxycinnamic, and 4-hydroxycinnamic acids), whose ring moieties underwent degradation only if oxygen was present. Under anoxic conditions, the substrates were merely modified (by side chain reduction and demethylation), and this modification occurred at the same time as a net accumulation of phenylpropanoids formed endogenously in the gut homogenate, a phenomenon not observed under oxic conditions. Enumeration by the most-probable-number technique revealed that each N. lujae gut contained about 10(sup5) bacteria that were capable of completely mineralizing aromatic substrates in the presence of oxygen (about 10(sup8) bacteria per ml). In the absence of oxygen, small numbers of ring-modifying microorganisms were found (<50 bacteria per gut), but none of these microorganisms were capable of ring cleavage. Similar results were obtained with gut homogenates of R. flavipes, except that a larger number of anaerobic ring-modifying microorganisms was present (>5 x 10(sup3) bacteria per gut). Neither inclusion of potential cosubstrates (H(inf2), pyruvate, lactate) nor inclusion of hydrogenotrophic partner organisms resulted in anoxic ring cleavage in most-probable-number tubes prepared with gut homogenates of either termite. The oxygen dependence of aromatic ring cleavage by the termite gut microbiota is consistent with the presence, and uptake by microbes, of O(inf2) in the peripheral region of otherwise anoxic gut lumina (as reported in the accompanying paper [A. Brune, D. Emerson, and J. A. Breznak, Appl. Environ. Microbiol. 61:2681-2687, 1995]). Taken together, our results indicate that microbial degradation of plant aromatic compounds can occur in termite guts and may contribute to the carbon and energy requirement of the host.

Interspecific Interactions in Phytophagous Insects: Competition Reexamined and Resurrected

This review reevaluates the importance of interspecific competition in the population biology of phytophagous insects and assesses factors that mediate competition. An examination of 193 pair-wise species interactions, repre­ senting all major feeding guilds, provided information on the occurrence, frequency, symmetry, consequences, and mechanisms of competition. Inter­ specific competition occurred in 76% of interactions, was often asymmetric, and was frequent in most guil ds (sap feeders, wood and stem borers, seed and fruit feeders) except free-living mandibulate folivores. Phytophagous insects were more likely to compete if they were closely related, introduced, sessile, aggregative, fed on discrete resources, and fed on forbs or grasses. Interference 297 0066-4170/95/0101-0297$05.00 A nn u. R ev . E nt om ol . 1 99 5. 40 :2 97 -3 31 . D ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g by T ex as S ta te U ni ve rs ity S an M ar co s on 0 5/ 16 /1 3. F or p er so na l u se o nl y. 298 DENNO, McCLURE & OTT competition was most frequent between mandibulate herbivores living in con­ cealed niches. Host plants mediated competitive interactions more frequently than natural enemies, physical factors, and interspecific competition. Sufficient experimental evidence exists to reinstate interspecific competition as a viable hypothesis warranting serious consideration in future investigations of the structure of phytophagous insect communities.

Feeding guilds of oribatid mites based on their carbohydrase activities

Carbohydrase activity was analysed in 49 species of oribatid mites and one acaridid mite sampled from natural populations. Enzyme activity was determined for the main differentiating food components: cellulose, a component of cell-walls of green plants; chitin, a component of fungal cell-walls; and trehalose, a component of fungal cell-contents. Feeding guilds were defined based on the activity of the three carbohydrases. The nomenclature of the feeding guilds was adopted from that of ruminants. Five major feeding guilds were distinguished: herbivorous grazers (9 species), fungivorous grazers (8), herbo-fungivorous grazers (16), fungivorous browsers (7) and opportunistic herbo-fungivores (8) and two minor guilds in oribatids: herbivorous browsers (1) and omnivores (1). The feeding guilds presented are operationally better defined in terms of resource exploitation than the macro-, micro- and panphytophages used hitherto.

TERRESTRIAL VERTEBRATES AND VEGETATION STRUCTURE IN THE WESTERN UNITED STATES

Terrestrial vertebrates in the western United States are functionally linked to environmental settings, as revealed by principal components analyses. Species number in five major vertebrate feeding guilds increases as vegetation structure becomes more complex and environmental conditions become more varied, and as evolutionary history has promoted species richness. Two other major vertebrate feeding guilds increase with temperature and evolutionary factors. Results support the view of animals as adapted parts of deterministic environmental systems, although complete explanations of species distributions require consideration of evolutionary history and stochastic processes.

Diversity of soft-bottom benthos in a tropical estuary: Gulf of Nicoya, Costa Rica

The community structure of soft-bottom infauna is described for the Gulf of Nicoya, Costa Rica, Central America, with special reference to the relationship between diversity and a tropical estuary. Of the 205 species of invertebrates collected in July, 1980, polychaetes comprised 58.6% by number of species and 68.1% by number of individuals. Density ranged from zero to 8 744 m-2 with a mean of 1 269 m-2 per station, and biomass ranged from zero to 10.986 g m-2 with a mean of 2.010 g m-2. Numerical analysis indicated considerable faunal homogeneity, characterized by polychaetes. Five major polychaete feeding guilds were recognized. From measures of diversity we concluded that the soft-bottom community of the Gulf of Nicoya was not rich for a tropical estuary. Physical processes (riverine runoff and frontal systems) mainly influenced community structure and function in the lower Gulf whereas biological processes (predation) seemed to prevail in the upper Gulf.

Changes in Bat Species Diversity along an Elevational Gradient up the Peruvian Andes

Changes in chiropteran species diversity and richness along a generalized transect up the eastern slopes of the Peruvian Andes are described. Variation in overall species diversity, species richness, and evenness are closely correlated with elevation. A decrease in bat density along the gradient is indicated by elevational decrease in sample size and by significant elevational reduction in the number of bats netted per unit effort. Explanations for these patterns are offered based on significant correlations of temperature and foliage height diversity with both overall richness and number of species in major feeding guilds. The conclusion is that diversity changes in the bat community along the gradient are caused by many factors, both historical and contemporary. The slopes of the Andes probably were colonized, for the most part, from the adjacent older lowlands of the Amazon Basin where most of the speciation took place. Immigration into the highlands has been (is) impeded by the reductions in temperature, habitat complexity, and levels of food abundance acting independently or collectively.