Plant-Animal Interactions

Dispersal is an important ecological process that affects plant population structure and community composition. Invasive plants with fleshy fruits rapidly form associations with native and invasive dispersers, and may affect existing native plant-disperser associations. We asked whether frugivore visitation rate and fruit removal was associated with plant characteristics in a community of fleshy-fruited plants and whether an invasive plant receives more visitation and greater fruit removal than native plants in a semi-arid habitat of Andhra Pradesh, India. Tree-watches were undertaken at individuals of nine native and one invasive shrub species to assess the identity, number and fruit removal by avian frugivores. Network analyses and generalised linear mixed-effects models were used to understand species and community-level patterns. All plants received most number of visits from abundant, generalist avian frugivores. Number of frugivore visits and time spent by frugivores at individual plants was positively associated with fruit crop size, while fruit removal was positively associated with number of frugivore visits and their mean foraging time at individual plants. The invasive shrub, Lantana camara L. (Lantana), had lower average frugivore visit rate than the community of fleshy-fruited plants and received similar average frugivore visits but greater average per-hour fruit removal than two other concurrently fruiting native species. Based on the results of our study, we infer that there is little evidence of competition between native plants and Lantana for the dispersal services of native frugivores and that more data are required to assess the nature of these interactions over the long term. We speculate that plant associations with generalist frugivores may increase the functional redundancy of this frugivory network, buffering it against loss of participating species.

Many plants produce structural defenses to deter feeding by herbivores. However, many previous studies testing whether spines are effective at defending against mammalian herbivores have produced equivocal results. These ambiguous results are hypothesized to be due to herbivore counter-adaptations. We investigated potential counter-adaptations in a population of white-throated woodrats Neotoma albigua that specialize on cactus by investigating feeding behavior and preference for cacti varying in spinescence. Neotoma albigula exhibited a unique behavior of clipping cactus spines, which renders these defenses ineffective. Strikingly, these woodrats chose to collect spiny cacti over experimentally de-spined cacti, demonstrating that spines act as a proximal cue that attracts woodrats. This attraction is likely due to the higher protein and lower fiber content of spiny cacti compared to naturally non-spiny cacti. Thus, the ‘defensive’ spines of cacti are ineffective against a specialist herbivore and instead serve as an indicator of nutritional quality that promotes herbivory. Our results support the ‘rule-of-thumb’ hypothesis of foraging, which states that herbivores forage according to obvious visual cues that are indicative of nutritional content, rather than sampling nutrient composition of plants. We propose that specialist herbivores are unique systems in which to study other counter-adaptations to structural defenses and ‘rule-of-thumb’ foraging strategies.

The abaxial leaf surfaces of Anomozamites villosus sp. nov., a new species of bennettitalean foliage from the Middle Jurassic Daohugou beds of Inner Mongolia, China, are covered with soft, shaggy hairs that are loosely, but regularly distributed across the lamina. Selectively arranged, long, stiff or acerate hairs directed or bent towards the leaf apex, project on the abaxial side of the leaf from the rachis margins. Both types of hairs are interpreted predominantly as adaptations for passive defence against damage by arthropods (sap-sucking, leaf-chewing or oviposition) rather than being morphological responses to physical environmental parameters, e.g. xeromorphic features. As several of the leaves show evidence for high levels of leaf-margin feeding by phytophagous arthropods, these mechanisms have not been entirely effective and may have evolved to defend against only selected arthropods or behavioural strategies. These findings contribute to the reconstruction of ecological interactions in the exceptionally preserved Jurassic Daohugou biota of northern China, and provide a rare insight into the plant–arthropod co-evolutionary ‘arms race’.

Roost ecology in bats is a complex interaction of behavioral, morphological and physiological adaptations, thus, there are many
factors involved in roost selection by bat species. Approximately 22 species of bats are able to modify leaves to establish their roost,
17 of which are in the Neotropics. Although there are many studies of tent-roosting bats, this is the first describing the structure of
the interaction between bats and the plants they are using as roosts. We describe a potential antagonistic network between these bats
and the plants used for tent construction in La Selva Biological Station in Costa Rica. We calculated descriptors of the network such
as the number of bats and plants interacting, as well as the number of pairwise interactions based on published records or direct
observations. We also tested for connectance and nestedness in the network structure. We propose a name for this non-trophic
antagonistic interaction, which is a structural antagonism, where bats damage the leaves, reducing their lifespan and the plant fitness.
In La Selva the network is composed of eight bats and 45 plant species reported by 60 pairwise interactions. Only 2.16% of vascular
plant species in La Selva are being modified as tents. The network had low connectance (0.167) and no significant nestedness or
modularity. Considering the species richness of plants in La Selva, there are few links between tent-roosting bats and plants species,
which shows the specialization of these interactions and the high dependence of most of these bats on a few plant species, even if
they are very specific and temporary resources.

Endozoochory is usually involved in seed dispersal mutualisms, whereas ectozoochory is non-rewarding, and therefore neutral (or even negative) for the animal vector. Synzoochory is an intermediate dispersal type between endo and ectozoochory in which propagules are deliberately transported (usually in the mouth) but with no ingestion or gut passage involved. We present empirical evidence of synzoochoric mutualism between the hummingbird Sephanoides sephaniodes and cryptogams (one fern and seven moss species). Two species (Lophosoria quadripinnata and Ancistrodes genuflexa) constituted the bulk of nest biomass, and another six moss species were  present in lesser quantity. The hummingbird was selective when collecting nest material so that the nests contained a higher density of reproductive structures (that could be dispersed further) than natural patches of the cryptogam species. Even after one year, the nests maintained half of the original reproductive structures (sporangia, sporophytes) and biomass, constituting an important dispersal source. These results show a new type of mutualism in which mosses could be dispersed throughout longer distances (several kilometers) by hummingbirds and to higher positions (particularly for ground-living species, promoting dispersal potential). The hummingbird benefits from collecting cryptogam material for nest building, and cryptogams benefit from the concentration and relocation of diaspore sources into more effective recruiting sites. Similar mutualistic relationships could be a general phenomenon, of importance in many ecosystems.

During a meeting of Mountain Coffee Producers, in Viçosa, Minas Gerais, in December 2009, 70 interviews were conducted. This study aimed to characterize the activity of the producers by geographical distribution, by cultivars coffee producers, by the livestock activities they perform and assess the interest in the consortium sheep and coffee. To the results, we applied the command proc freq SAS System for Windows NT, version 8.0, licensed by the Universidade Federal de Viçosa (SAS, 1999). Three groups of producers were identified: only coffee producers (A), coffee producers and sheep growers that don’t intercrop these cultures (B) and those that do intercrop (C). They were from the mesoregion of Zona da Mata, microregions of Viçosa (81.4%), Uba (5.7%), Muriaé (5.7%), Manhuaçu (5.7%). Only one was from the mesoregion of Vale do Rio Doce, microregion of Caratinga (1.5%). Two coffee species were grown by respondents, with 98.5% Arabica, variety Catuaí and Mundo Novo, and 1.5% Conilon. Of the producers interviewed, 34.3% did not have any animal husbandry on their properties. For the others, the most frequent cattle husbandry was cattle (25.7%), followed by cattle with other species (20.0%), poultry (15.7%), pig (2.9%) and horse husbandry (1.4%). Of the interviewers, 40% had an interest in sheep husbandry and 68.6% of them had thought in the possibility of sheep grazing in-between the coffee plantations when it have no fruit.

En el bosque montano de los Andes del norte existe un vacío en el conocimiento sobre interacciones ecológicas de los colibríes. Los factores que pueden determinar la estructura de la red planta-colibrí y sus características son abundancia, fenología o restricciones morfológicas. Estudié colibríes y las plantas que visitan en el bosque de Unchog (Departamento de Huanuco, Perú) de 2011 a 2014. La red de colibríes fue construida con observaciones directas. Una interacción se definió cuando visitaron y consumieron el néctar. La abundancia de aves fue determinada usando redes de niebla y la de plantas contando flores. La fenología se midió cuando una especie de planta y una de colibrí estaban presentes. Las restricciones morfológicas provocan "interacciones prohibidas", que se determinaron midiendo el pico del colibrí y comparándolo con la longitud de las flores. La teoría de redes se aplicó utilizando R y algoritmos desarrollados por investigadores con las mismas preguntas ecológicas. Los visitantes más importantes en la red fueron los colibríes Metallura theresiae y Pterophanes cyanoptera. Tomando en cuenta todas las aves que visitaron las plantas con flores, el perforador de flores, Diglossa mystacalis fue abundante. Las plantas más visitadas fueron el arbusto Brachyotum lutescens y el muérdago Tristerix longebracteatus. El análisis demostró que la fenología es el mejor predictor de la estructura de la red. Algunos colibríes superan interacciones prohibidas tal vez por el efecto de perforadores de flores; por lo que la morfología no fue el principal impulsor de la estructura de la red. Considerando interacciones legales o ilegales en la red; la fenología fue en ambos casos el predictor más importante de la estructura de la red. Con el inminente efecto del cambio climático causando desajuste fenológico en la biodiversidad de las montañas tropicales, estos resultados refuerzan la necesidad de protección de los colibríes y sus hábitats.

Most herbivores are facultative generalists and include a variety of plant species and plant parts in their diet that vary in nutrient content. To counter herbivory, many plants produce secondary metabolites (PSMs) that can act as toxins or digestibility reducers. When choosing a food item, herbivores therefore face a trade-off between the nutritional benefits and the physiological and behavioural costs, or effort invested, in dealing with these anti-herbivore plant traits. PSMs also vary within a backdrop of primary plant constituents, including nutrients. This variation means that animals have the potential to choose amongst a wide array of combinations of plant primary and secondary chemistry.  Furthermore, because PSMs can interact biochemically with nutrients and with each other in the gut of herbivores, the choices that herbivores make when deciding what to eat are likely to be both complex and diverse.
The details of how PSMs and nutrients shape the behavioural foraging strategies of herbivores have been widely studied in captive animals with the focus almost always on individual components of diet and diet choice. In contrast, this thesis takes a wide and inclusive approach towards understanding the foraging behaviours of free-ranging mammalian browsers using the Swamp Wallaby (Wallabia bicolor) as a model. To achieve this, my research has four main goals: 1) to assess the importance of vegetation structure and composition in the foraging decisions of herbivores; 2) to determine whether volatile PSMs can have multiple functions in the foraging of free ranging herbivores; 3) to define how the chemical composition of food sources can alter the foraging decisions of free ranging herbivores; and 4) to elucidate if the availability of choice can affect the capacity of herbivores to deal with plant toxins.
In order to achieve these goals I used the Giving-up Density (GUD) methodological framework throughout my thesis. This is a framework for field studies that imposes an exponentially increasing harvesting cost as food is consumed at patches. The GUD framework has a series of advantages and disadvantages that became obvious during my research. Therefore, I decided to dedicate my last chapter (5) to the review and discussion of the methodology, and the construction of a comprehensive guide showing practical approaches that can be used to tackle any problems with this methodology.
For my first aim, I compared GUDs left by swamp wallabies with the vegetation characteristics (Cover, richness and diversity) of the area surrounding each feeding station. I found some support to the importance of plant community compositions in influencing the foraging decisions of this mammalian herbivore, and no evidence of structural characteristics playing any role in this process.
For my second aim, I compared the foraging response of brushtail possum (Trichosurus vulpecula) and the swamp wallaby (Wallabia bicolor) to the volatile terpene 1, 8-cineole, as a potential odour cue and a dietary toxin. I use feeding stations with food and an inedible matrix that varied in content of a volatile terpene, 1, 8-cineole. Cineole in the matrix worked as a masking odour for wallabies but not for possums, suggesting that odour may be an important foraging cue only for wallabies, and the differences between the species can be explained by the ecological niche and diet of each species. I suggested that plant volatiles can be used by herbivores as a cue that allows them to select particular plants or plants parts from a patch.
For my third aim, I tested the foraging response of free-ranging swamp wallabies to artificial foods that varied in the PSM 1, 8-cineole; primary constituents (including nitrogen and fibre); and a factorial combination of both. Swamp wallabies show an increasing GUD with higher cineole level in food, and with higher nutrient level wallabies lowered their GUD. I demonstrated that nutrients and cineole impart an interactive effect on GUD, and high nutrient food required substantially more cineole to achieve the same GUD as low nutrient food. Therefore, nutrient-rich plants may face the exacerbated problem of not only being preferred by herbivores, but of needing to produce comparatively more defence compounds to achieve the same level of protection as low nutrient plants.
For my final experimental aim, I investigated the effect of choice in the overcoming of the toxic effects of a PSM, 1, 8-cineole. I tested dietary regimens at two different concentrations of cineole. To do this, I offered swamp wallabies a choice between (i) a high protein diet (HP) and a high carbohydrates (HC) diet; (ii) a no-choice preferred diet formulated to reflect the mixture of protein and carbohydrate selected when animals had access to both HP and HC foods; and (iii) a ‘no-choice basal’ (food with no added protein or carbohydrates). Higher cineole caused an increase in GUD, however, HP:HC ratio did not change with cineole treatment. I argue that this may be a consequence of swamp wallabies relying on foraging cues, such as flavours or odours, to assess food quality, which may have been negated due to the method use to prepare these diets.
Finally, in my review of the literature of the current uses of the Giving-p Density framework (GUD), I outline the theoretical and practical benefits of the methods as well as seven issues that need consideration when applying this methodology. I suggested that the incorporation of complementary methods (such as cameras) to better understand the foraging processes involved in the GUD itself, concluding that these methods can potentially offer novel and important insights into the study of foraging behaviour.
Through the evidence I have collected, it is clear that when herbivores decide where to forage, the processes influencing these decisions are more complex than the simple additive effects of individual plant characteristics or their distribution in the landscape. By not relying on limited offers of different plants or food type, as captive trials often do, I have included the variability characteristic of naturals systems, and yet demonstrated that the influence of plant chemistry on foraging is robust. I think the approach I took has been insightful on the subject of herbivore foraging, and has offered good support to our growing understanding on this area of ecology. It is important to continue testing these hypotheses in the complex background offered in nature.

The authors of this edition propose a novel and inspiring research approach to the subject of plants, which – being a form of life that is different, yet akin to us – is a constant source of nourishment and metaphors, decoration and obsessions. The articles included in this thematic block on plants enter into lively ongoing debates on genetics, feminism, ecology and plant ontology. They are excellent examples of the fact that in Polish philosophical and cultural reflection there was an understanding very early on of the challenges that posthumanism poses to our anthropocentric intellectual habits. Foreign readers will recognize in these Polish reflections a bold willingness to ask ethical and aesthetic questions of great relevance to the modern world that go far beyond the safe, though most likely imagined, limits of what it is to be human.

One of the major issues facing humankind is global food security. A changing climate, coupled with a heightened consumer awareness of how food is produced and legislative changes governing the usage of agrichemicals for improving plant health and yield, means that alternative, more integrated and sustainable approaches are needed for crop management practices. To this end, there is increasing recognition of the value of the role of microbial inoculants in agriculture. The focus of this review is to understand how plant-growth-promoting bacteria and arbuscular mycorrhizal fungi can play a part in improving crop yield by promoting the health status of the plant through the sequestration of various nutrients and in the control of plant diseases.

We invite you to submit high quality of research papers in all areas of Life Sciences for the publication in & Trends in Biosciences  & Advances in Life Sciences”.

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The nurse-protégé hypothesis states that adult plants of one species provide micro-environmental con-ditions that favor the establishment of seedlings of a second species with no effect for the first species.Several studies suggest this effect should be prevalent in arid and semiarid zones as adult plants oftenprovide shelter from low moisture and high temperature. Echinopsis chiloensis and Eulychnia acida areendemic columnar cacti that inhabit the arid and semiarid zones of Chile. In this study, we examined thepattern of recruitment of both cactus species at Reserva Nacional Las Chinchillas, located ∼60 km eastfrom the Pacific coast. We determined number, growth and survivorship of young cacti (<30 cm height)through biannual monitoring between 2009 and 2012 in microhabitats that strongly differ in their abi-otic variables (minimum and maximum temperature and mean relative humidity, moisture content, andphysical and chemical soil characteristics), under five different shrub species and in open spaces, andexamined the association of these cacti with potential nurse plants. Most young cacti occurred undershrubs, the microhabitat having the lowest mean and maximum temperatures and the highest relativehumidity. In particular, E. chiloensis and E. acida were found under the shrubs Flourensia thurifera and Bahiaambrosioides, respectively, in a higher frequency than expected by chance, suggesting that these shrubspecies behave as nurse plants through species-specific effects than are not accounted for by differencesin soil nutrients.

Premise of research. Biotic interactions have long been considered to be of less importance in structuring desert systems than other ecosystem types, but biotic interactions often play a critical role in meeting the challenges posed by the extreme conditions of desert environments. The Sonoran Desert, in particular, is home to several textbook examples of mutualisms, such as the interactions between the iconic saguaro cactus and its bat pollinators. But what do we know about the diversity, ecology, and evolution of plant-animal, plant-plant, and plant-microbe interactions and their impacts on individual plants and plant species in the Sonoran Desert? Methodology. To address this question, we review the published research on seven common kinds of plant biotic interactions by revisiting the respective literature, identifying gaps in our knowledge, and outlining future research directions. Pivotal results. Numerous gaps in our knowledge of plant biotic interactions in the Sonoran Desert were identified. Studies of insect herbivory, bee pollination, and plant-microbe interactions are poorly represented in the Sonoran Desert literature. Across all categories of interaction, few have examined the impacts of interactions on plant fitness or context-dependent variation in the outcomes and strengths of interactions. For the most part, interactions have been studied at single locations and over short periods of time, resulting in an incomplete understanding of their diversity, ecology, and evolution. Conclusions. Plant biotic interactions shape the habitats in which they occur and play an important role in the maintenance of species diversity. Therefore, we call for increased efforts to fill the gaps in our understanding of plant biotic interactions in the Sonoran Desert, with an emphasis on studies linking interactions to plant fitness and the context-dependent nature of interactions. Without this knowledge we have limited capacity to predict the outcomes of global change on species interactions and to develop measures to conserve the biodiversity of the Sonoran Desert region.

Abrupt collapse of the tropical rainforest biome (Coal Forests) drove rapid diversification of Carboniferous tetrapods (amphibians and reptiles) in Euramerica. This finding is based on analysis of global and alpha diversity databases in a precise geologic context. From Visean to Moscovian time, both diversity measures steadily increased, but following rainforest collapse in earliest Kasimovian time (ca. 305 Ma), tetrapod extinction rate peaked, alpha diversity imploded, and endemism developed for the first time. Analysis of ecological diversity shows that rainforest collapse was also accompanied by acquisition of new feeding strategies (predators, herbivores), consistent with tetrapod adaptation to the effects of habitat fragmentation and resource restriction. Effects on amphibians were particularly devastating, while amniotes ('reptiles') fared better, being ecologically adapted to the drier conditions that followed. Our results demonstrate, for the first time, that Coal Forest fragmentation influenced profoundly the ecology and evolution of terrestrial fauna in tropical Euramerica, and illustrate the tight coupling that existed between vegetation, climate, and trophic webs.

SUMMARY: Each spring, the introduction of up to 3000 beehives is permitted in the Teide National Park (Tenerife, Islas Canarias). This introduction implies that around 100 million Apis mellifera (Apidae) bees compete with the native fauna (insects, but also birds and lizards) for floral resources (nectar/pollen). Since A. mellifera is not considered an effective pollinator (qualitatively), its massive presence can also reduce fruit and seed production, and the viability and vigour of seeds and seedlings by inbreeding depression. We document the ecological consequences of massive honeybee introduction on the native pollination network of this protected area (with a high frequency of Canarian endemic species) and we also review examples worldwide about their impact on insular flora and fauna. Our results indicate that both the structure and functionality of the pollination network were negatively, and significantly affected under the massive presence of A. mellifera. When beehives were installed into the Park, the diversity of native flower visitors decreased. Besides, the reproductive performance of highly visited plant species by honeybees (Echium wildpretii and Spartocytisus supranubius) was significantly reduced. According to these results, we recommend the complete suppression of introduced beehives in Teide National Park in order to protect its endemic flora and fauna.

RESUMEN: En el Parque Nacional del Teide (Tenerife, Islas Canarias)  se autoriza, cada primavera, la introducción de unas 3000 colmenas de abeja doméstica (Apis mellifera, Apidae). Esto implica que unos 100 millones de abejas melíferas compiten por néctar y polen con la fauna polinizadora nativa (insectos, aves y lagartos) de este ecosistema peculiar de alta montaña. Si tenemos en cuenta que A. mellifera es considerada como un polinizador poco eficaz, la masiva presencia de abejas domésticas puede además incidir negativamente tanto en la producción de frutos y semillas como en la viabilidad de las semillas y el vigor de las plántulas. El objetivo de este artículo es señalar las consecuencias ecológicas de la introducción de A. mellifera en la red de interacciones mutualistas en esta área protegida (con un elevado porcentaje de especies endémicas), además de revisar el impacto de la abeja doméstica sobre la flora y fauna nativa en otros sistemas insulares. Los resultados obtenidos muestran que la diversidad de polinizadores disminuye sustancialmente tras la introducción de A. mellifera. Además, se detecta una reducción significativa en la eficacia reproductiva de aquellas plantas (Echium wildpretii, Spartocytisus supranubius) frecuentemente visitadas por A. mellifera. Por todo ello, y en base a los resultados obtenidos, se recomienda eliminar completamente la presencia de colmenas en el interior del Parque Nacional del Teide con el fin de proteger su flora y fauna endémica.

In recent years, humanists and social scientists have shown increasing interest in human-animal relations – to the point where many now speak of an ‘animal turn’ in the humanities and social sciences. Across history, psychology, anthropology, literature, sociology, philosophy, and law, an interdisciplinary field of human-animal studies has been forming. Certain common themes run through this diverse field, not least the reproduction of human-animal difference, and the conditions and the implications thereof.

Despite the long history of language use as a marker of such difference, the academic quest to investigate the boundary between human and nonhuman has, somewhat surprisingly, not taken root within rhetorical studies – at least not until now. For this edited volume, we therefore call for chapters that investigate the place of nonhuman animals in the purview of rhetorical theory; what it would mean to communicate beyond the human community; how rhetoric reveals our ‘brute roots.’ In other words, this book invites contributions which enlighten us about likely or possible implications of the animal turn within rhetorical studies. Would such a turn imply, for instance, that rhetoric needs a nonanthropocentric reconfiguration? The question, perhaps, is this: What difference would it make to the discipline if we assumed that nonhuman forms of communication were as interesting as human ones?

“O rizoma é uma estrutura de pensamento inteiramente alternativa e bizarra. O rizoma tende a crescer na horizontal, imediatamente abaixo ou acima do solo, criando estolhos. É impossível classificar, orientar ou intervir no seu crescimento. O rizoma não tem um princípio ou um fim, carece de qualquer eixo de indexação ou de simetria. É caracterizado por um intervalo sem significado. O rizoma pode quebrar-se num ponto e reconectar-se por completo sem perder o seu sentido, porque em vez de ter um sentido ele produ-lo. O rizoma tem memória curta. Ele convive com a própria amnésia porque não há ninguém a quem se possa queixar. É caracterizado pela anti-genealogia: gera múltiplas versões dos acontecimentos, muitas vezes contraditórias, e favorece a liberdade e o acaso.”

"The Cactaceae is a diverse and conspicuous Neotropical family that has evolved a wide variety of adaptations during co-evolution with their interacting species. Recent research has indicated complex ecological and evolutionary interactions involving cacti and other organisms. In the framework provided by ecological interactions theory we show four case studies involving cacti: (1) the evolutionary ecology of a mistletoe–cactus parasitism in central Chile; (2) the effect of an exotic grass on the demography of a threatened cactus in Puerto Rico; (3) the herpetochory in the genus Melocactus in Venezuela; and (4) the
role of abiotic and biotic factors on the floral morphology in eight cacti in northern Chile. In addition, we highlight some key aspects that might be useful as guidelines and recommendations for structuring future research and collaborative efforts in cactus biology research; these are related to the development of a cactus interaction database that integrates published information; in invasion biology, aspects that account for eventual detrimental effects of invasive species to cactus diversity; and the role of multi-species interactions such as pollination, seed dispersal and nurse plant associations for the maintenance of cacti and the ecosystem services that they provide."

Plants are of fundamental importance to the structure, functioning and service provision of many ecosystems. However, herbivores can have negative ecological and socioeconomic effects on plant communities through consumption, trampling and alteration of nutrient cycles. In this thesis I address a particular herbivore-plant interaction: the grazing of plants in chalk river catchments, principally the submerged macrophyte water crowfoot (Ranunculus penicillatus ssp. pseudofluitans (Syne) S.D. Webster) and terrestrial pasture grass species, by flocks of non-breeding mute swans (Cygnus olor Gmelin, 1789). This research was carried out over two years in the River Frome catchment (Dorset, UK).

Based on a meta-analysis of previous waterfowl grazing studies I show that waterfowl biomass density (kg ha-1) rather than individual density (ind. ha-1) is a better predictor of reductions in plant standing crop. Most studies to date have analysed such reductions using only individual densities, despite large between-taxa variation in waterfowl body mass, diet and intake rates.

I quantified the abundance, species richness, evenness, flowering and dominance of the chalk river aquatic plant community in relation to biotic and abiotic factors during the growth-, peak-, and recession-phases of the growth cycle. The relative importance of herbivory, riparian shading, water temperature and distance downstream varied between different phases of the plant growth cycle, highlighting the importance of seasonal patterns in regulation of plant community structure.
The River Frome swan population varied seasonally, being highest in the winter. The population was dominated by non-breeding adults and juveniles that lived in flocks. These flocks exhibited strong seasonal habitat switches between terrestrial pasture in winter and spring, and river in summer and autumn. I provided evidence that this switch was linked to the seasonal decrease in water velocity between spring and summer, which reduced the metabolic costs of river feeding and increased the relative profitability of aquatic food resources.

I used a mathematical population model and an individual-based behavioural model respectively to explore two management options for the alleviation of the swan grazing conflict in chalk rivers: population control and habitat alterations. Population control measures, such as clutch manipulations, fertility control, culling or translocations, were predicted to be unsuccessful except at impractically high levels of management effort, due to the effects of immigration and high survival rates in offsetting removed eggs or individuals. Habitat alterations, in particular the narrowing of river channels to cause a local increase in water velocity and thus swan foraging costs, are more promising management options as they require lower management effort, are less ethically controversial, and address the fundamental reason why swans select their food resources, the rate of net energy gain (‘profitability’).

Evidence for invertebrate feeding on glossopterid gymnosperms is documented from Middle Permian silicified peats of the Prince Charles Mountains, Antarctica, in the form of coprolites occurring both free in the peat matrix and clustered within excavations in roots, aerial wood and leaves. Observations of coprolites in thin-sections of the peats and from scanning electron microscopy of examples extracted via bulk maceration reveal nine morphotypes distinguished by size, shape, surface texture and contents. These include coprolites with coarse plant debris, spirally ornamented coprolites, coprolites containing spore/pollen remains and fern sporangia, coprolites within Glossopteris leaves, an ellipsoidal morphotype within a fern sporangium, large isolated coprolites between matted leaves, clustered forms filling galleries inside Vertebraria roots and Australoxylon wood, forms with coarse indeterminate constituents and others with fungal contents. Other faunal evidence is limited to indeterminate arthropod exoskeleton fragments. Collectively, the coprolites within the permineralised peat from the Prince Charles Mountains document the presence of diverse feeding behaviours including stem feeding, sporangial feeding, palynivory, root feeding and mycophagy. The first evidence of invertebrate feeding traces in Vertebraria (glossopterid) roots is identified. These findings indicate that herbivory by invertebrates in the high-latitude Permian forest-mire ecosystems of Antarctica was more intense and diverse than previous studies have reported, and affected all parts of the Glossopteris plant, together with components of associated herbaceous taxa.

Herbivory is a fundamental process that controls primary producer abundance and regulates energy and nutrient flows to higher trophic levels. Despite the recent proliferation of small-scale studies on herbivore effects on aquatic plants, there remains limited understanding of the factors that control consumer regulation of vascular plants in aquatic ecosystems. Our current knowledge of the regulation of primary producers has hindered efforts to understand the structure and functioning of aquatic ecosystems, and to manage such ecosystems effectively. We conducted a global meta-analysis of the outcomes of plant–herbivore interactions using a data set comprised of 326 values from 163 studies, in order to test two mechanistic hypotheses: first, that greater negative changes in plant abundance would be associated with higher herbivore biomass densities; second, that the magnitude of changes in plant abundance would vary with herbivore taxonomic identity. We found evidence that plant abundance declined with increased herbivore density, with plants eliminated at high densities. Significant between-taxa differences in impact were detected, with insects associated with smaller reductions in plant abundance than all other taxa. Similarly, birds caused smaller reductions in plant abundance than echinoderms, fish, or molluscs. Furthermore, larger reductions in plant abundance were detected for fish relative to crustaceans. We found a positive relationship between herbivore species richness and change in plant abundance, with the strongest reductions in plant abundance reported for low herbivore species richness, suggesting that greater herbivore diversity may protect against large reductions in plant abundance. Finally, we found that herbivore–plant nativeness was a key factor affecting the magnitude of herbivore impacts on plant abundance across a wide range of species assemblages. Assemblages comprised of invasive herbivores and native plant assemblages were associated with greater reductions in plant abundance compared with invasive herbivores and invasive plants, native herbivores and invasive plants, native herbivores and mixed-nativeness plants, and native herbivores and native plants. By contrast, assemblages comprised of native herbivores and invasive plants were associated with lower reductions in plant abundance compared with both mixed-nativeness herbivores and native plants, and native herbivores and native plants. However, the effects of herbivore–plant nativeness on changes in plant abundance were reduced at high herbivore densities. Our mean reductions in aquatic plant abundance are greater than those reported in the literature for terrestrial plants, but lower than aquatic algae. Our findings highlight the need for a substantial shift in how biologists incorporate plant–herbivore interactions into theories of aquatic ecosystem structure and functioning. Currently, the failure to incorporate top-down effects continues to hinder our capacity to understand and manage the ecological dynamics of habitats that contain aquatic plants.

Though the concept of edge effect is existed widely it has not been well tested not known or applied in tropical environments. Having a higher rate of declining forest cover (33.2% to 29.7% within the last decade) there is an emerging need to apply conservation theories in action in order to protect country’s inherent communities of flora and fauna.
The study is conducted from December 2013 to May 2014 in Gannoruwa forest reserve, a secondary montane forest which is located in Kandy district aiming to investigate the difference between avian communities which associated with forest for quantification of edge effect and the importance of ecosystem for conservation of avifauna.
Four 100m long parallel belt transects were delimited to edge. Elevation levels of transects were A=557.2m – 558.5, B= 562.7m – 567.3, C= 584.8m – 592.73, D= 610.0m – 632.76m.  Transects were at least 50m apart. 5 sample points in each trail were established at 20m intervals. Floristic composition and avian communities were censused at each sample point using circular point sampling technique. The relative canopy cover was estimated using densitometer and digital photographs using Photoshop software.
2544 bird individuals censused belonging to 91 species distributed across 4 established transects. Shannon-weiner diversity indices of communities obtained as 3.205±0.051, 3.507±0.061, 2.959±0.084, 3.070±0.072 respectively, while Simpson’s index for communities obtained using minimum variance unbiased estimator method as 0.060±0.0064, 0.034±0.0059, 0.064±0.01268, 0.052±0.0077. This indicates higher avifaunal diversity along transect B, A & D respectively. Evenness of avifaunal assemblages was high in community B and least in community C. Morisita’s overall community similarity value was 0.570±0.042 and highest similarity was observed between community C&D (0.678±0.09), B&D (0.667±0.08) and B&C (0.611±0.08) while least was observed between A&D (0.425±0.07) indicating avian assemblages in edge different than forest interior.
Canopy covers of transects were significantly different (P=0.001) and Avian diversity showed a negative correlation with canopy cover (p=0.305). A negative correlation was observed between elevations and diversity (p=0. 248), evenness (p=0.653). Positive (r=0.243) but not significant (p=0.365) relationship was observed between plant diversity and avian diversity.
The results clearly indicate that the edge and the area immediately to the edge are vital for survival of edge preferred birds. Thus, conservation activities should be more focused on disturbances to forest edges than forest interiors.

Food caching is widespread among several animal species. Few studies have proposed that handling time should affect the
evolution of caching behavior, especially under foraging time constraints. Nevertheless, to date, there has been no analytical
support to the ‘‘handling time hypothesis.’’ In the present article, we use an analytical model to show that caching behavior may
evolve as the result of shorter handling time caching relative to eating. We evaluate caching behavior under 3 fitness objectives
(or environmental scenarios): maximizing energy consumed, maximizing and balancing energy consumed, and maximizing
energy consumed under risk of predation. Our analyses reveal that under all 3 fitness objectives, caching behavior can evolve
when caching time is shorter than eating time, to allow the animal to free up search time during the period when food is plentiful
and postpone time spent handling to the period when food is scarce and search time is less valuable. That effect may be called
‘‘search time reallocation,’’ and it is still prevalent even if food decays. Our model provides predictions that can be field tested,
adds to the debate of handling time and perishability hypotheses, and invites researchers to direct their focus toward understanding
the evolutionary motives of caching behavior.

We propose the new nothogenus, ×Cohnlophiaris Cetzal & Balam (Cohniella×Lophiaris) based on a natural intergeneric hybrid, ×Cohnlophiaris quintanarooensis Cetzal & Carnevali (Cohniella ascendens×Lophiaris oerstedii) from a locality in Quintana Roo, Mexico, which is here described and illustrated. The new nothospecies is vegetatively similar to C. ascendens but the flowers show intermediate characters between the putative parents. ×Cohnlophiaris quintanarooensis is similar to C. ascendens by having yellow petals and sepals with brown or reddish spots, transversely subquadrate central lobe, central keel parallel to the proximal and distal teeth, and pollinarium of Cohniella type. On the other hand, is it similar to L. oerstedii in the papillose abaxial surface of petals and sepals, the oblong lateral lobes of the labellum, the subquadrate column base, the pentagonal cavity stigmatic and the pink clinandrium. A key to diagnose the new intergeneric hybrid and its putative parents, a comparative figure and a map showing their geographical distribution are provided.

Mimulus luteus (Scrophulariaceae) is a perennial herb occurring in the South American Andes that shows a wide variation in the size and shape of a red spot on the lower lobe of the yellow flower. We describe the preference of four insects (three bees and one butterfly) and one hummingbird species for floral characters, and estimated the strength, direction, and form of pollinator-mediated selection through female fitness. We applied geometric morphometrics to describe the preference of pollinator species for different guide shapes. Our results revealed striking differences in the floral phenotypes preferred by insects and hummingbirds. Insects visited flowers with corollas 1.25-fold larger and guides 1.72-fold larger than the hummingbird species did. While insects preferred flowers with nectar guides pointing toward the corolla tube, the hummingbird preferred flowers with heartshaped nectar guides. Most of the floral preferences shown by pollinators translated into significant linear and nonlinear selection coefficients. When selection was analyzed on a per-flower basis and for female fitness, corolla size was under positive directional selection, and nectar guide size and shape were under disruptive selection. Because the insect and hummingbird pollinators showed a strong segregation in their daily activity time, we suggest that current disruptive selection on the nectar guide phenotype can result from the differential availability of the rewarding floral variants over a day. Our findings suggest that pollinator-mediated selection favoring extreme phenotypes in M. luteus may not only contribute to high nectar guide variation found in this species, but also can promote divergence of corolla and nectar guide traits.

1. While many studies of flower evolution have relied on the assessment of selection coefficients, these estimates represent correlative evidence of selection. Few studies have combined correlative with experimental evidence, and hence the mechanisms underlying selection processes are not well understood.

2. In this study we quantified the magnitude, direction and form of pollinator-mediated selection acting upon morphological traits in the Chilean endemic orchid Chloraea bletioides. Results revealed strong selection differentials for plant height and flower number, and absence of total selection for morphological flower characters. Multivariate analysis of selection revealed a strong and positive directional selection gradient for flower number.

3. The labellar lobe and flower tube were under negative correlational selection, indicating that selection promoted alternative combinations of traits. Plants with long floral tubes and small labellar lobes, and short floral tubes with large labellar lobes were selected for. Interestingly, selection on flower number increased at a higher rate through the female function than through the male function, which suggests that size-dependent resource limitation may be more important than pollinator-mediated selection for fruit set.

4. In addition to estimates of phenotypic selection, we evaluated through phenotype modification the impact of pollinators on the correlation and potential integration of flower traits coming from different whorls. We removed the tip of the lateral sepals and the labellar lobe in a 2 x 2 factorial design.

5. Results revealed that phenotypic modification had no effect on male and female fitness. The absence of effect was consistent with the low and non-significant selection coefficients. Nevertheless, the observation of significant correlational selection for labellar lobe and flower tube suggests that experimental studies performed on these characters may be of interest to evaluate the functional and adaptive integration of flower design in orchids.

Relation between grasses and large herbivores at the Ulu Muda salt licks, Peninsular Malaysia. Ulu Muda Forest Reserve is known for its salt licks and grassy floodplains. Previous studies largely overlooked the floristic component of Gramineae in this herbivore-rich forest. This paper reports on the dominant grass species present at Sira Bongor, Sira Keladi and Sira Air Hangat salt licks, namely, Hymenachne amplexicaulis, Centotheca lappacea and Oryza ridleyi and describes the niches occupied by grasses at the three sites in relation to signs of large herbivore activities. Preliminary evidence indicated that the salt licks and adjacent H. amplexicaulis swamps were dynamic habitats, plausibly created and maintained by large-bodied herbivores including elephants. The presence of grasses that extended the role of salt licks as places for both minerals and nutritive food intake for large herbivores was discussed.

The Teno range of mountains, located in the northwest Tenerife, Canary Islands, is still a refuge for the flora and fauna of the island. Until now, at least four native species of reptiles, 232 of birds (both breeding and migrant), and six mammals have been recorded for that site. For some of these animals, such as Canarian Spotted Lizard (Gallotia intermedia), Manx Shearwater (Puffinus puffinus), Osprey (Pandion haliaetus), Rock Sparrow (Petronia petronia) and Northern Raven (Corvus corax), these cliffs, gorges, tablelands or forests hold a good part or all of their insular populations. This illustrated and annotated checklist synthesizes and updates the available information on terrestrial vertebrates for the entire northwestern area of Tenerife. A current and comprehensive list of extant species supports effective management strategies and conservation projects as well as the efficient dissemination of information regarding this Natural Heritage.

The functional or structural linkage among traits [phenotypic integration (PI)] within complex structures can constrain the evolutionary response of individual traits. To analyse whether frugivores with distinct sensory ecology have shaped the patterns of fruit diversification differently, we compared PI values of fleshy fruits that are consumed by birds and mammals. We used phylogenetic comparative analyses of PI among 13 morphological, nutritional and visual fruit traits from 111 Mediterranean plant species. Results showed that morphological traits had higher PI values than nutritional and colour traits. Visual and nutritional traits show positive phylogenetic covariance, while negative covariation occurs between fruits size and nutrients. Importantly, fruits consumed by birds were relatively more integrated than fruits consumed partly or solely by mammals. Hence, we show that major groups of mutualistic frugivores can shape the covariance among some fruit traits differently and thereby influence fruit diversification.

1. Information on direct and indirect drivers of temporal variation in ant-plant interactions is scarce, compromising our ability to predict the functioning of these ecologically important interactions. 2. We investigated the roles of precipitation, ant activity, abundance of young plant tissues bearing extrafloral nectaries (EFNs) and EFN phenotypes in the establishment of EFN-mediated ant-plant interactions throughout the year in Amazonia, Brazil. We hypothesized that the frequency of ant-plant interactions follows a predictable seasonal pattern, being higher in wetter periods, during which plants invest more in the production of new plant tissues bearing EFNs, ultimately promoting ant attendance. We surveyed and tagged every understorey Bignonieae plant rooted inside 28,500-m 2 plots, and recorded ant-EFN interactions on each plant five times throughout the year. We also sampled ants with honey baits to estimate temporal variation in general ant activity. 3. Contrary to our hypothesis, the proportion of plants tended by ants in each plot was higher in drier, not wetter, months. Ant attendance was indirectly and negatively related to precipitation, which was attributed to a decrease in the proportion of plants producing new EFN-bearing plant tissues during the wetter period. Additionally, seasonal variation in an ant activity did not explain temporal patterns of plant attendance. At the plant level, ant attendance increased strongly with the number of recently formed shoot nodes, and ants almost never attended plants with limited or no young tissue. Among the 12 most abundant Bignonieae species, the amount of young tissue was the most important predictor of ant attendance, secondarily explained by the EFN secretory area. 4. Synthesis. Our results suggest that seasonal variation in the production of new plant tissues bearing EFNs is the primary driver of the temporal patterns of EFN-plant

Ant–plant symbioses involve over 110 ant species in five subfamilies that are facultative or
obligate occupants of stem, leaf or root domatia formed by hundreds of ant-plant species.
The phylogenetic distribution and geological ages of these associations, and the frequency of
gains or losses of domatium, are largely unknown.

We compiled an up-to-date list of ant domatium-bearing plants, estimated their probable
true number from model-based statistical inference, generated dated phylogenies that include
c. 50% of ant-plant lineages, and traced the occurrence of domatia and extrafloral nectaries
on a 1181-species tree, using likelihood and Bayesian methods.

We found 681 vascular plants with domatia (159 genera in 50 families) resulting from minimally
158 inferred domatium origins and 43 secondary losses over the last 19 Myr. The oldest
African ant–plant symbioses are younger than those in Australasia and the Neotropics. The
best statistical model suggests that the true number of myrmecophytes may approach 1140
species.

The phylogenetic distribution of ant-plants shows that domatia evolved from a range of
pre-adapted morphological structures and have been lost frequently, suggesting that domatia
have no generalizable effect on diversification. The Miocene origin of ant–plant symbioses is
consistent with inferred changes in diet and behaviour during ant evolution.