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Since the early nineteenth century, critics have noted John Clare’s unusually attentive eye for animals. From his earliest published pieces to the final poems transcribed from manuscripts in Northampton Asylum, Clare’s poetry is packed with animal life. This piece closely reads two sonnets from the middle of his career to investigate the breadth and complexity of his engagement with multiple non-human modes of being. It then turns to a representative range of other examples from his work and touches briefly upon critical analogies drawn between the poet and the non-human creatures about which he writes. The piece focuses repeatedly on the variety in Clare’s representations of animals and the consequent difficulty of drawing singular critical conclusions from them. In the process, it explores tensions in Clare’s poetry between themes of interconnection and alienation, freedom and confinement, profusion and scarcity, resilience and fragility, and exposure and agency.
Invasive species threaten biodiversity on a global scale. The success of invasions depends on the species' adaptation to the different environmental conditions of new territories. Studies show that invasive insects present evolutionary changes in wing morphology in areas they are introduced to in response to abiotic conditions. In the last decade, the Asian Drosophila nasuta fly invaded and spread widely throughout Brazil. This insect has preferences for conserved environments and is related to the likely reduction in the abundance of native drosophilids in the Atlantic Forest. Ecological niche modelling analyses showed that rainfall and temperature are the main factors which delimit the geographic distribution of this species. Herein, we verified the existence of significant differences in the wing sizes of D. nasuta in Brazil and evaluated the influence of abiotic factors (rainfall and temperature) on the observed patterns. We conducted 11 measurements on the right-side wings of 240 D. nasuta males collected in the Amazon Forest, Caatinga, Cerrado and Atlantic Forest. Statistical analyses revealed the existence of two groups: one with larger wings, which brought together samples from locations with the lowest temperatures; and one with smaller wings, which corresponded to places with a hotter climate. One explanation for this result is the fact that large wings favour greater heat capture by flies in colder climates, increasing their survival chances in these environments. These rapid evolutionary changes in D. nasuta in this first decade of invasion in Brazil reveal the enormous adaptive potential of this species in this megadiverse country.
Effective early detection, monitoring and management methods are critical for reducing the impacts of insect pests in agriculture and forestry. Combining host plant volatiles with sex pheromones could enhance trapping methodologies, whilst the use of non-host volatiles could improve the effectiveness of pest management through repellency effects. In this meta-analysis approach, we analysed 51 studies that used electroantennograms (EAG), wind tunnels and/or field traps to evaluate the antennal and behavioural responses of Lepidoptera to sex pheromones combined with attractant or repellent plant volatiles. Proposed attractant plant volatiles had a positive association with female Lepidoptera responses to sex pheromone, but effects on males were highly variable, with unexpected repellency reported in some studies. Proposed repellent plant volatiles were significantly or near-significantly negatively associated with male attraction to sex pheromones but were scarcely studied. Sub-group analysis identified that male responses to sex pheromone were reduced when the dose of attractant plant volatile relative to sex pheromone was increased. Green-leaf volatiles were associated with the strongest positive effects for males in field traps. Multiple-compound attractant plant volatile blends were less effective than single compounds in field studies. Our analysis demonstrates, (i) the potential value of combining host plant volatiles with sex pheromones to capture females rather than only males, (ii) the importance of identifying appropriate host plant volatiles and optimal relative doses, and (iii) the potential for non-host plant volatile use in pest management strategies.
This chapter considers the associations between animality and aviation in the 1930s. It begins by explaining how Garnett’s reading of the Russian entomologist Boris Uvarov was crucial to his completion of his novel The Grasshoppers Come (1931), which contains such convincing depictions of insects that Uvarov suspected Garnett had viewed them first-hand (the letters Uvarov wrote to Garnett are here reproduced for the first time). Reading this novel alongside his diary-record of learning to fly, A Rabbit in the Air (1932), the first half of the chapter goes on to analyse how Garnett’s texts present an aesthetics of flight that hinges on connections and dissonances between human, animal and machine. The second part illustrates how Garnett’s aeronautical writing extended to the context of war and the publication of War in the Air (1941), which he wrote for the Air Ministry. By avoiding associations that had by the Second World War become bound up in nationalist bombast, Garnett subverts the increasingly masculinist and militarist approach to technology and animality found in other writings as the decade progressed.
This chapter focuses on E. M. Forster’s A Passage to India (1924) to explore Forster’s repeated, if sometimes reluctant, interest in modes of animality that threaten to unravel his humanism and complicate what critics, most notably Edward Said, have claimed to be his orientalising descriptions of the country and its people. It begins by looking at Forster’s depiction of beetles and wasps in the novel, examining how his later paratextual notes, added in 1942, undercut taxonomic precision. When placed in the context of the rise in popular entomology, Forster’s ‘unentomological’ approach to insects emerges as an important aesthetic feature of the novel. In part, it signals Forster’s hesitancy to impose western systems of knowledge on India, while it also differentiates his use of beastly language from writings by René Maran and Mulk Raj Anand. Bringing in intertextual material from Forster’s earlier novel Howards End (1910) and later account of visits to India, The Hill of Devi (1953), the chapter goes on to explore how he stages encounters with vaguely understood animal figures in which his anti-imperialism becomes, ironically, clearer.
Bergmann’s Rule describes an increase in the body size of endothermic animals with decreasing environmental temperatures. However, in ectothermic insects including moths, some of the few existing studies investigating size patterns along temperature gradients do not follow the Bergmann’s Cline. Intraspecific differences in moth sizes along spatiotemporal temperature gradients are unknown from the Palaeotropics, hindering general conclusions and understanding of the mechanism responsible. We measured intraspecific forewing size differences in 28 Afrotropical moth species sampled in 3 seasons along an elevational gradient on Mount Cameroon, West/Central Africa. Size increased significantly with elevation in 14 species but decreased significantly in 5 species. Additionally, we found significant inter-seasonal size differences in 21 species. Most of these variable species had longer forewings in the transition from the wet to dry season, which had caterpillars developing during the coldest part of the year. We conclude that environmental temperature affects the size of many Afrotropical moths, predominantly following prevailingly following Bergmann’s Cline. Nevertheless, the sizes of one-third of the species demonstrated a significant interaction between elevation and season. The responsible mechanisms can thus be assumed to be more complex than a simple response to ambient temperature.
The ant in Robert Hooke’s compendium and celebration of microscopy in Micrographia: or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses (1665) uniquely resists scientific scrutiny: moving about when alive, too-easily crushed when dead, the ant proves to be insistently difficult to study under a microscope. Through an extended allusion to Richard Ligon’s A True and Exact History of the Island of Barbadoes (1657), Hooke links the unruly ant to the colonial economy of enslaved Africans in Barbados, a place that Ligon understands through sugarcane, enslaved Africans, and saltwater slavery. The story of Hooke’s ant in Micrographia uncovers what Lisa Lowe calls the “intimacy” of modern, Western liberalism and the global conditions upon which it depends. In this case, Hooke’s ant reveals the intimacy of early scientific practice and the institution of transatlantic chattel slavery, exposing in the process that a small thing can reveal vast scales of geography and their networks of exploitation.
Social wasps have a widespread Neotropical distribution and are important pollinators and biological control agents for pest insects. The foraging activity of wasps is influenced by biotic and abiotic factors that are detected by the antennal sensilla that vary according to species, sex, caste, and environmental conditions. This study compares the types and quantities of antennal sensilla with a scanning electron microscope between the nocturnal Apoica flavissima and the diurnal Polistes simillimus wasps. Six types of sensilla were found in the antennae of both species: placoid, coeloconic, basiconic-type 1, basiconic-type 2, trichoid-type 1, and trichoid-type 2. Sensilla chaetica were found only in the scape and pedicel of A. flavissima. In the nocturnal wasp, there are 19,132.27 ± 1,247.72 sensilla in the left and 17,746.46 ± 1,477.46 in the right antennae, whereas in the diurnal wasp 14,936.72 ± 1,271.69 in the left and 16,090.82 ± 1,345.3 in the right antennae. A. flavissima has a longer antennal length and number of sensilla than P. simillimus. The higher number of antennal sensilla in the nocturnal wasp is not linked with the antennal size. The association of antennal sensilla functions with ecological and behavioral factors of A. flavissima and P. simillimus are discussed.
In order to assemble an ecological community it may be helpful to know not only how many parts there are, but what kinds of parts there are. Communities require at least two classification systems that provide simultaneous and somewhat contradictory lists of parts: phylogenetic and functional. These two classification systems can be arranged hierarchically so that many parts (species) are nested within a smaller number of groups (functional types). Even with objective classification techniques, it is difficult to know how many groups exist, and the number selected may be somewhat arbitrary. There does not seem to be a way to tell, a priori, how many functional types we can expect to find in a specified landscape or habitat. This raises difficult questions about the nature of fitness landscapes and the geometry of n-dimensional trait space.
This piece explores possible reasons for Lucilius’ suggestive reference to worms, emblemate uermiculato, in the famous comment (about speech arranged akin to mosaics) which has survived from Book 2 of the satirist. The fragment can be set metatextually amid other extracts of Lucilius to show the poet's agency and skill, considered as having influenced aspects of its own afterlife (especially in Hor. Sat. 2.4) and appreciated in its historical context as a hit at Publius Mucius Scaevola, who died from phthiriasis.
The legume pod-borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) (LPB), is an important insect pest of pigeon pea. Chemical pesticides are generally employed to manage this pest, but because of the soil residue issues and other environmental hazards associated with their use, biopesticides are also in demand. Another benign alternative is to use entomopathogenic nematodes (EPNs) to manage this vital pest. In the present study, the infectivity of ten native EPNs was evaluated against LPB by assessing their penetration and production in the LPB. The effectiveness of the promising EPNs against second-, third- and fourth-instar LPB larvae was also studied. Heterorhabditis sp. (Indian Agricultural Research Institute-Entomopathogenic Nematodes Rashid Pervez (IARI-EPN RP) 06) and Oscheius sp. (IARI-EPN RP 08) were found to be most pathogenic to LPB, resulting in about 100% mortality within 72 h, followed by Steinernema sp. (IARI-EPN RP 03 and 09). Oscheius sp. (IARI-EPN RP 04) was found to be the least pathogenic to LPB larva with 67% mortality. Maximum penetration was exhibited by Heterorhabditis sp. (IARI-EPN RP 06) followed by Oscheius sp. (IARI-EPN RP 08), whereas the lowest rate of penetration was exhibited by Oscheius sp. (IARI-EPN RP 01). The highest rate of production was observed with Oscheius sp. (IARI-EPN RP 08), followed by Oscheius sp. (IARI-EPN RP 04 and 10). Among the tested instars of the LPB larvae, second-instar larvae were more susceptible to EPNs, followed by third- and fourth-instar larvae. The results indicate that Heterorhabditis sp. (IARI-EPN RP 06) and Oscheius sp. (IARI-EPN RP 08) have a good potential to the manage LPB.
Dietary deficiencies in Fe and Zn are globally widespread, causing serious health problems such as anaemia, poor pregnancy outcomes, increased risk of morbidity and mortality, stunted growth and impaired physical and cognitive development. Edible insects, of which a diversity of over 2000 species is available, are dietary components for about 2 billion individuals and are a valuable source of animal protein. In the present paper, we review the available information on Fe and Zn in edible insects and their potential as a source of these micronutrients for the rapidly growing human population. The levels of Fe and Zn present in eleven edible insect species that are mass-reared and six species that are collected from nature are similar to or higher than in other animal-based food sources. High protein levels in edible insect species are associated with high Fe and Zn levels. Fe and Zn levels are significantly positively correlated. Biochemically, Fe and Zn in insects occur predominantly in non-haem forms, bound to the proteins ferritin, transferrin and other transport and storage proteins. Knowledge gaps exist for bioavailability in the human alimentary tract, the effect of anti-nutritional factors in other dietary components such as grains on Fe and Zn absorption and the effect of food preparation methods. We conclude that edible insects present unique opportunities for improving the micronutrient status of both resource-poor and Western populations.
Arthropod communities in the tropics are increasingly impacted by rapid changes in land use. Because species showing distinct seasonal patterns of activity are thought to be at higher risk of climate-related extirpation, global warming is generally considered a lower threat to arthropod biodiversity in the tropics than in temperate regions. To examine changes associated with land use and weather variables in tropical arthropod communities, we deployed Malaise traps at three major anthropogenic forests (secondary reserve forest, oil palm forest, and urban ornamental forest (UOF)) in Peninsular Malaysia and collected arthropods continuously for 12 months. We used metabarcoding protocols to characterize the diversity within weekly samples. We found that changes in the composition of arthropod communities were significantly associated with maximum temperature in all the three forests, but shifts were reversed in the UOF compared with the other forests. This suggests arthropods in forests in Peninsular Malaysia face a double threat: community shifts and biodiversity loss due to exploitation and disturbance of forests which consequently put species at further risk related to global warming. We highlight the positive feedback mechanism of land use and temperature, which pose threats to the arthropod communities and further implicates ecosystem functioning and human well-being. Consequently, conservation and mitigation plans are urgently needed.
The growing global demand for soybeans due to its different uses and by-products, as well as its use in the diet of several livestock species, is forcing the industry to seek alternative protein sources. Environmental concerns related to huge volumes of poultry manure serve as a warning for the choice of more sustainable production systems. Thus, the current review investigates the processing of an insect meal as an alternative protein source to feed broilers. The five desirable features in the selection of insect species proposed by the Food and Agriculture Organization (FAO) show that the high productivity of biomass, feed conversion efficiency and the organic waste conversion capacity from poultry farms is aided by the use of larvae from housefly and black soldier fly species. Brazilian production of such insects is possible due to climatic and environmental conditions and has the potential to supply part of the protein demands of the Brazilian poultry industry when raised in controlled environments. The prevalence of tropical climatic conditions and the possible use of organic waste from poultry farms as substrate can mitigate some environmental issues as well as generate income to smallholder farms prevailing in this activity.
Ring artifacts are undesirable and complicate the analysis and interpretation of microstructures in synchrotron X-ray microtomography. Here, we propose a new method to improve the image quality of an object by removing the ring artifacts and investigate the efficiency of this process with tomographic images of a dried Tenebrio molitor. In this method, before the tomographic reconstruction, ring artifacts were identified and located in the sinograms as line artifacts. Then, the identified line artifacts were corrected as single point noise via image processing of the original projections. Eventually, the corresponding line artifacts were removed, resulting in reduced ring artifacts in the reconstructed tomographic images. Simulations verified the efficiency of the proposed method. This method was successfully applied for the structural analysis of the insect T. molitor, showing superior performance in reducing ring artifacts in the tomographic image without noticeable loss of structural information.
The Fernbank interglacial site, on the west side of Cayuga Lake, New York, has been recently subjected to more detailed study. To a lengthened mollusc list are added ostracodes, insects, fish, pollen, and plant macrofossils. Of these, plants are well preserved and diverse, whereas other groups are poorly preserved and incomplete. Nevertheless, all support the interglacial assignment (Sangamon), which is further supported by minimum age radiocarbon dates (>50,000 14C yr BP) and a TL date of 81 ± 11 ka. In the plant record near the top of the sequence, abundant tree charcoal indicates forest fires. Like the Toronto interglacial record, the plants show a declining July mean temperature from 24 to 18°C (according to transfer functions) through the sequence, from mixed deciduous forest to boreal forest.
Most management tactics used against leafy spurge are not economical, practical, or efficacious when used alone. Combinations of the biological control agent, Aphthona beetles, the herbicide imazapic (105 g/ha), and interseeded native grass species were evaluated for leafy spurge management at two sites: Sheyenne National Grassland and Ekre Grassland Preserve in North Dakota during 2001 to 2005. At the Sheyenne site, over a 5-yr study period, leafy spurge was reestablishing its stem density after a single application of imazapic, but stand suppression was maintained to < 11 stems/m2 when management combined imazapic with Aphthona or interseeding of native grasses. Aphthona beetles established at the Sheyenne site, but declined as leafy spurge density decreased. However, the remaining Aphthona population continued to suppress leafy spurge density. Leafy spurge stem control was successfully maintained for 3 yr by Aphthona and grass competition without repetition of the imazapic treatment. Leafy spurge root dry weights were reduced by 66% (< 111g/m2) in the insect plots during this period. At the Ekre site, similar results were observed for the first 3 yr. However, in the fourth yr, a failure of biological control agents to establish resulted in the resurgence of leafy spurge. During this study, lower Aphthona emergence was observed in imazapic-treated plots, possibly due to reduced leafy spurge density.
The relative importance of different bottom-up-mediated effects in shaping insect communities in tropical secondary forests are poorly understood. Here, we explore the roles of vegetation structure, forest age, local topography (valley vs. hill top) and soil variables in predicting fruit-feeding butterfly and tree community composition, and tree community composition in predicting fruit-feeding butterfly community composition, in different-aged naturally regenerating and primary forests of Kibale National Park, Uganda. We also examine which variables are best predictors of fruit-feeding butterfly species richness or diversity. Butterflies (88 species) were sampled with a banana-baited trap and trees (98 taxa) with a 40 × 20-m sampling plot at 80 sampling sites. The environmental variables explained 31% of the variation in the tree community composition, the best predictors being local topography, forest age and cover of Acanthus pubescens (a shrub possibly arresting succession). The fruit-feeding butterfly community composition was better predicted by tree community composition (explaining 10% of the variation) rather than vegetation structure, local topography or soil factors. Environmental variables and tree species richness (or diversity) were poor predictors of butterfly species richness (or diversity). Our results emphasize the importance of tree community to recovery of herbivorous insect communities in tropical secondary forests.
This paper outlines and discusses the fossil record of the Hemiptera – the fifth most diverse insect order. The diversity of these insects in comparison with the “Big Four” group is given, together with a short history of its classification. Updated information is presented about the fossil record of particular families, with a brief analysis. The main evolutionary traits of the major Hemiptera lineages are briefly described. The influence of biotic interactions with endosymbionts, shaping the evolution of the hemipterans as well as abiotic events and major global changes, is disputed. The innovations and perils of the evolutionary history of the Hemiptera are presented.
Temperature is arguably the most important abiotic factor influencing the life history of ectotherms. It limits survival and affects all physiological and metabolic processes, including energy and nutrient procurement and processing, development and growth rates, locomotion ability and ultimately reproductive success. However, the influence of temperature on the energetic cost of development has not been thoroughly investigated. We show that in the diamondback moth [Plutella xylostella L. (Lepidoptera: Plutellidae)] rearing temperature (range10–30°C) affected growth and development rates, the energetic cost of development and fecundity. Rearing at lower temperatures increased development times and slowed growth rate, but resulted in larger adult mass. Fecundity was lowest at 10°C, highest at 15°C and intermediate at temperatures of 20°C and above. At a given rearing temperature fecundity was correlated with pupal mass and most eggs were laid on the first day of oviposition, there was no correlation between total eggs laid and adult longevity. The highest production cost was incurred at 10°C; this decreased with increasing temperature, was minimized in the range 20–25°C, and then increased again at 30°C. These minimized production costs occurred at temperatures close to the intrinsic optimum temperature for this species and may reflect the rearing temperature for optimal fitness. Thus at sub-optimal temperatures greater food resources are required during the development period. Predicted increased temperatures at the margins of the current core distribution of P. xylostella could ameliorate current seasonal effects on fecundity, thereby increasing the probability of winter survival leading to more resilient range expansion and an increased probability of pest outbreaks.