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Samuel Holker Haslam (1797–1856) was an English naturalist whose plant and insect specimens are extant in several museum collections. Born into a family of cotton manufacturers in Lancashire, Haslam used his inherited wealth to set himself up as a country gentleman, eventually settling near Milnthorpe in Westmorland. He was a bibliophile, subscribing to several important fine colour-plate books on natural history and gardening, a Fellow of the Linnean Society of London and a member of many other societies spanning botany, entomology, palaeontology, agriculture and antiquarianism. He collected primarily in the Lake District (Westmorland, Cumberland and north Lancashire), West Yorkshire, Cheshire, Cambridgeshire, Gloucestershire, Somerset and the Channel Islands, especially Guernsey. His activities exemplify the role played by independent collectors in documenting early nineteenth-century British natural history. [ABSTRACT FROM AUTHOR]

This paper summarises significant events in the life of Francis Edward Joseph Strickland from his birth in 1691 at the exiled Stuart Court in Saint-Germain-en-Leye, near Paris, to his death in Carlisle during the 1745 Jacobite rebellion. Emphasis is placed on his various roles in the Stuart court and his involvement in the 1715 and 1745 Jacobite rebellions, including his malign influence on Bonnie Prince Charlie and his deteriorating relationship with his godfather James Francis Stuart, the Old Pretender. His life is evaluated in the context of his role and status within the wider exiled Jacobite circle. [ABSTRACT FROM AUTHOR]

This article examines the abundance, life history, host-plant relationships, and overwintering biology of Acyrthosiphon calvulus Ossiannilsson (Homoptera: Aphididae) as a precursor to understanding its rarity and potential response to a changing climate. Acyrthosiphon calvulus is restricted to a few scattered localities on the west coast of Spitsbergen, Svalbard, Norway, where it reproduces on Salix polaris WG (Salicaceae) and its taxonomically unrelated root parasite Pedicularis hirsuta L. (Scrophulariaceae) . Acyrthosiphon calvulus overwinters as eggs. Hatching fundatrices give rise directly to males and oviparae, which mate and lay overwintering eggs. The life cycle is closely synchronized with the phenology of S. polaris and appears genetically programmed, lacking summer generations of viviparae. Alate forms are similarly unknown. The progeny sequence of fundatrices resulted in a sex ratio for the sexuales that is strongly female biased (3:1). Eggs hatch coincided with budburst in early June and fundatrices developed on the expanding leaves. Egg production by oviparae corresponded with leaf senescence in July and August. Overwintering egg survival was high, with supercooling points ranging from −29 to −40 °C, lower than the extreme winter minimum temperature recorded (−28 °C). Egg development and hatching occurred at or below 5 °C and sub-zero temperatures were not required to break diapause. The scarcity and fragmented distribution of A. calvulus is discussed in the context of the ubiquity of its host plants on Spitsbergen. [ABSTRACT FROM AUTHOR]

Abstract: Pyrolysis–gas chromatography/mass spectrometry was used to compare soil carbon samples from a glacier-retreat chronosequence in the high Arctic. The analysis considered the relative abundance of different pyrolysis products in an attempt to distinguish significant shifts in the soil-C pool. The relative abundance of the compound classes, pyridines, furfurals, phenols, aromatic hydrocarbon precursors, and cyclopentanones were compared. Based on principal component analysis that explained 90% of the variance in the first and second components, the compound classes were well separated. As such, the compound classes selected were well suited for identifying differences among the samples. The most obvious change indicated the appearance of ligninaceous material in the soil-C pool. This shift appeared to occur between 60 and 100 years after glacial retreat. Another less obvious shift was the change from a largely animal dominated early colonization to algae. This shift occurred between 2 and 16 years after glacial retreat. The results suggest that pyrolysis–gas chromatography/mass spectrometry (pyrolysis–GC/MS) can be an effective tool for drawing distinctions between soil-C at different sites and relationship to cover matter. [Copyright &y& Elsevier]

Developmental response to temperature during the critical early season growing period was investigated in two congeneric species of Craspedolepta feeding on Epilobium angustifolium at three sites at different altitudes in Norway and the UK. The larval development reaction norm to temperature, measured as accumulated day degrees, was not significantly different between Craspedolepta nebulosa and Craspedolepta subpunctata at sites where they co-occurred but C. nebulosa development was consistently more advanced at any site. For individual species the reaction norms at the lowest site (Ainsdale, UK) were similar to the intermediate site (Geilo, Norway): and there were no differences between years. Insect size remained relatively constant. However, at the highest site (Haugastøl, Norway), where C. subpunctata is unable to complete its development, the reaction norm for C. nebulosa was significantly higher than at Geilo and the individual insects produced were smaller. These adaptations allow life-history completion under limiting temperature conditions. An experiment at Ainsdale, to raise the mean temperature by around 2.5°C during the early growing season, resulted in accelerated development in both C. nebulosa and C. subpunctata but development in C. nebulosa was accelerated proportionately more. C. nebulosa thus displays the greater plasticity in developmental response to environmental temperature that allows it to occupy a greater altitudinal and latitudinal range than C. subpunctata, in which the response is less plastic and more canalized. The likely individualistic responses of the two species to climate warming are considered. [ABSTRACT FROM AUTHOR]

Open Top Chambers (OTCs) were used to measure impacts of predicted global warming on the structure of the invertebrate community of a Dryas octopetala heath in West Spitsbergen. Results from the OTC experiment were compared with natural variation in invertebrate community structure along a snowmelt transect through similar vegetation up the adjacent hillside. Changes along this transect represent the natural response of the invertebrate community to progressively longer and potentially warmer and drier growing seasons. Using MANOVA, ANOVA, Linear Discriminant Analysis and χ2 tests, significant differences in community composition were found between OTCs and controls and among stations along the transect. Numbers of cryptostigmatic and predatory mites tended to be higher in the warmer OTC treatment but numbers of the aphid Acyrthosiphon svalbardicum, hymenopterous parasitoids, Symphyta larvae, and weevils were higher in control plots. Most Collembola, including Hypogastrura tullbergi, Lepidocyrtus lignorum and Isotoma anglicana, followed a similar trend to the aphid, but Folsomia bisetosa was more abundant in the OTC treatment. Trends along the transect showed clear parallels with the OTC experiment. However, mite species, particularly Diapterobates notatus, tended to increase in numbers under warming, with several species collectively increasing at the earlier exposed transect stations. Overall, the results suggest that the composition and structure of Arctic invertebrate communities associated with Dryas will change significantly under global warming. [ABSTRACT FROM AUTHOR]

1. Craspedolepta nebulosa and C. subpunctata were studied on their shared host plant Epilobium angustifolium along an altitudinal transect in the Hardangervidda area of southern Norway. 2. The following was investigated: whether (a) the altitudinal distribution and abundance of each psyllid species was determined by summer heat budgets, acting directly on rates of insect development and/or through their host plant and (b) whether parasitism, predation, and interspecific competition played any role in restricting the distribution of the two species . 3. Craspedolepta nebulosa extended to higher elevations than C. subpunctata but within their ranges neither species showed a clear altitudinal trend in abundance per plant. However, the former species grew to a smaller size with increasing elevation. 4. There was little evidence for interspecific competitive effects and observed levels of parasitism and predation were negligible across the transect. 5. Development and distribution of both species mirrored significant differences in the phenology, size, leaf number, and reproductive output of E. angustifolium with increasing altitude. 6. Distributions were related to available heat budgets acting on psyllid/plant development rates, with C. nebulosa developing more efficiently at lower heat availability. 7. Population transplant experiments supported the overall conclusions, with neither psyllid species able to establish viable populations above their current upper altitudinal range limit, despite the presence of their host plant. [ABSTRACT FROM AUTHOR]

The literature on the response of insect species to the changing environments experienced along altitudinal gradients is diverse and widely dispersed. There is a growing awareness that such responses may serve as analogues for climate warming effects occurring at a particular fixed altitude or latitude over time. This review seeks, therefore, to synthesise information on the responses of insects and allied groups to increasing altitude and provide a platform for future research. It focuses on those functional aspects of insect biology that show positive or negative reaction to altitudinal changes but avoids emphasising adaptation to high altitude per se. Reactions can be direct, with insect characteristics or performance responding to changing environmental parameters, or they can be indirect and mediated through the insect's interaction with other organisms. These organisms include the host plant in the case of herbivorous insects, and also competitor species, specific parasitoids, predators and pathogens. The manner in which these various factors individually and collectively influence the morphology, behaviour, ecophysiology, growth and development, survival, reproduction, and spatial distribution of insect species is considered in detail. Resultant patterns in the abundance of individual species populations and of community species richness are examined. Attempts are made throughout to provide mechanistic explanations of trends and to place each topic, where appropriate, into the broader theoretical context by appropriate reference to key literature. The paper concludes by considering how montane insect species will respond to climate warming. [ABSTRACT FROM AUTHOR]

1. Ten Arctic species of Collembola and two species of cryptostigmatic mites survived anoxia at 5 °C over periods ranging from 1 to 36 days. 2. Highly active, surface-dwelling collembolans such as Isotoma anglicana, Isotoma tschernovi, and Sminthurides malmgreni were the most susceptible to anoxia. Mites and Collembola living deeper in the soil or in wet habitats, such as Camisia anomia and Hypogastrura viatica, were most tolerant. Tolerance, however, appears more closely linked to taxonomic relatedness than to ecological groupings per se, although the two may coincide. 3. Implications for life-history strategies, including metabolic cold adaptation in its broadest sense, are discussed. [ABSTRACT FROM AUTHOR]

Summerhayes and Elton's (1923) “nitrogen cycle” diagram for Bear Island (Bjørnøya), Svalbard, is widely used to illustrate the organisation of high Arctic food webs. We present a revision of the terrestrial section of this food web based on 12 years work on Spitsbergen, Svalbard. The level of complexity is much greater than Summerhayes and Elton suggested and the implications for ecological theory are discussed. In particular the low level of primary productivity does not appear to restrict the length of ectotherm food chains. This may in part be due to the open nature of the ecosystem, which receives energy/nutrient subsidies in the form of allochthonous wind-blown insects and detritus, particularly from surrounding aquatic environments. Connectivity is also significantly higher. Our data support the increasingly accepted view that many food webs presented in the literature are gross oversimplifications and that analysis of their structure can produce misleading conclusions. [ABSTRACT FROM AUTHOR]

1. Invertebrate community assembly is described for two contrasting proglacial chronosequences (over 1900 years) at Kongsfjord, W. Spitsbergen, Svalbard. 2. Three hypotheses were tested: (1) community assembly is deterministic, directional and predictable; (2) succession is inextricably linked to plant community and soil development; and (3) dispersal is a rate-limiting factor for community assembly. 3. Communities, dominated by omnivores and detritivores, are more complex than supposed previously. Herbivore species were few but predators, parasitoids and hyperparasitoids were abundant. 4. Species fell within one of eight defined groups with respect to colonization. This relates to ecophysiological tolerances, need for facilitation or dependence on other species. Spiders, surface-active Collembola and drought-resistant cryptostigmatic mites arrived before vascular plants established and soils developed. Later colonizers required site facilitation through soil development or host availability. 5. Comparisons between the proglacial area of Midtre Lovénbre, a land-terminating glacier, and three Lovén Islands, released from beneath a tidewater glacier, showed similarities in community composition and species abundance with respect to successional stage, suggesting determinism and direction in community development. 6. Most common species on Midtre Lovénbre colonized the Lovén Islands rapidly, suggesting that dispersal does not seriously restrict community development on the time scales involved. Some minor species associated with older soils appear not yet to have reached the islands. [ABSTRACT FROM AUTHOR]

Summary 1 Community assembly is described for two contrasting high Arctic chronosequences representing glacial regression of up to 2000 years on Svalbard. The chronosequences included a nutrient-poor glacier foreland (Midtre Lovénbre) and a series of nutrient-enriched islands (Lovén Islands) progressively released from below a tidewater glacier. 2 Soil development and community assembly paralleled proglacial sequences elsewhere but time scales were extended and mature vegetation types comprised species-poor prostrate communities. 3 Initial colonization by Cyanobacteria stabilized soil surfaces and raised nutrient status. Cyanobacteria formed the dominant ground cover (up to 34%) for 60 years, after when they declined. 4 Vascular plants established slowly and represented minor components of ground cover for the first 100 years. Earliest colonizers were often species with ectomycorrhizal associations, followed by mid-successional species that tended to disappear as ground cover increased. Some species present in the mature vegetation at the oldest sites, established only after 60+ years. 5 Species richness of vascular plants increased for c . 100 years, beyond when only occasional species were added. Bryophytes became increasingly dominant with time. 6 Soil development on the Midtre Lovénbre and Lovén Island chronosequences was similar after 100 years. Differences subsequently developed, with organic horizon depth, percentage organic matter and water content on the older Lovén islands significantly greater than at equivalent Midtre Lovénbre sites. This was associated with increased bryophyte cover but lower vascular plant species richness. One explanation is a slightly more favourable microclimate, coupled with nutrient input from nesting birds. 7 Communities progressively recruit from a limited pool of effectively dispersed species, each with particular ecological requirements that determine their point of entry into the community. A... [ABSTRACT FROM AUTHOR]

Summary 1 It is proposed that as a general rule primary community assembly by autotrophs is preceded by a previously unrecognized heterotrophic phase that may be instrumental in facilitating the establishment of green plants and consolidating the assembly process. 2 This heterotrophic stage, of variable duration, involves the allochthonous input of both dead organic matter and living invertebrates sufficient to allow the initial establishment of functioning communities comprised of scavenging detritivores and predators. 3 Evidence for deposition of such materials onto newly exposed land surfaces and the development of such animal communities is summarized for a variety of sites and substrates worldwide. 4 It is suggested that these heterotrophic communities conserve nutrients, particularly nitrogen, and facilitate the establishment of green plants. [ABSTRACT FROM AUTHOR]

Spiders are the earliest colonisers of newly exposed moraine substrates on the glacier foreland of the Midtre Lovénbreen at Ny-Ålesund, W. Spitsbergen, Svalbard (78°N). Spider densities are highly correlated with allochthonous inputs of potential prey items, predominantly chironomid midges. Large allochthonous inputs of insects potentially provide significant quantities of nitrogen and phosphorus to the developing ecosystem from the earliest stages of succession, even before a conspicuous cyanobacterial crust has formed. Spiders entrap nutrients and their possible broader role in early ecosystem development is discussed. [ABSTRACT FROM AUTHOR]

Summary1. Salix lapponum host plants at an upper altitudinal site differed significantly in size, structural density, phenology, growth performance, and spatial isolation from those growing at a lower site. 2. Plant differences were paralleled by significant differences in psyllid population density and phenology parameters, with psyllid population density, percentage of catkins occupied, and phenological development relatively lower or retarded at the upper site. Population densities at the upper site, nevertheless, remained high. 3. Plant measurements were good predictors of insect density, often explaining up to 73% of the variance in abundance among plants at a given site. 4. Sets of four plant characters identified by best subsets regression were better predictors of psyllid density and development than single factors, although differences were often not great and the combinations of characters selected by multiple regression sometimes differed from the best single predictors. 5. Best single predictors of psyllid density on catkins were measurements of plant size, particularly height, length, and basal stem diameter. Shoot density and catkin phenology were occasionally important but plant isolation and prior growth performance were less important. 6. By contrast with density, age structure of the psyllid population was predicted best from plant phenological measurements, notably catkin phenology. [ABSTRACT FROM AUTHOR]

The site of a Beaker burial excavated in Levens Park, Cumbria was published by David Sturdy in 1972 as that of a farmstead or place for the living altered into a ring cairn or place for the dead. However, the recent discovery of the excavation archive and contemporary correspondence reveals a far more complex monument than previously understood. We draw attention to a series of important omissions from the excavation report, provide a detailed account of the excavated monument and seek to create a new narrative regarding its development and purpose. We argue that the monument was built as a series of changing structures and demonstrates the idea of monuments in progress and, thereby, the creation of communal memory and identity. The absence of a full report of this excavation means that its wider significance has remained unknown. It represents one of the earliest examples of what Sturdy called 'rescue archaeology' and demonstrates a complex sequence of structural components and burial that contributes to our understanding of the Early Bronze Age. The broader archaeological appraisal of Levens Park, which provided the context for this excavation, represents one of the earlier examples of landscape archaeological survey in Britain. [ABSTRACT FROM AUTHOR]

Recently, there have been several studies using open top chambers ( OTCs) or cloches to examine the response of Arctic plant communities to artificially elevated temperatures. Few, however, have investigated multitrophic systems, or the effects of both temperature and vertebrate grazing treatments on invertebrates. This study investigated trophic interactions between an herbivorous insect ( Sitobion calvulum, Aphididae), a woody perennial host plant ( Salix polaris) and a selective vertebrate grazer (barnacle geese, Branta leucopsis). In a factorial experiment, the responses of the insect and its host to elevated temperatures using open top chambers ( OTCs) and to three levels of goose grazing pressure were assessed over two summer growing seasons (2004 and 2005). OTCs significantly enhanced the leaf phenology of Salix in both years and there was a significant OTC by goose presence interaction in 2004. Salix leaf number was unaffected by treatments in both years, but OTCs increased leaf size and mass in 2005. Salix reproduction and the phenology of flowers were unaffected by both treatments. Aphid densities were increased by OTCs but unaffected by goose presence in both years. While goose presence had little effect on aphid density or host plant phenology in this system, the OTC effects provide interesting insights into the possibility of phenological synchrony disruption. The advanced phenology of Salix effectively lengthens the growing season for the plant, but despite a close association with leaf maturity, the population dynamics of the aphid appeared to lack a similar phenological response, except for the increased population observed. [ABSTRACT FROM AUTHOR]

AbstractThis review examines the direct effects of climate change on insect herbivores. Temperature is identified as the dominant abiotic factor directly affecting herbivorous insects. There is little evidence of any direct effects of CO2 or UVB. Direct impacts of precipitation have been largely neglected in current research on climate change. Temperature directly affects development, survival, range and abundance. Species with a large geographical range will tend to be less affected. The main effect of temperature in temperate regions is to influence winter survival; at more northerly latitudes, higher temperatures extend the summer season, increasing the available thermal budget for growth and reproduction. Photoperiod is the dominant cue for the seasonal synchrony of temperate insects, but their thermal requirements may differ at different times of year. Interactions between photoperiod and temperature determine phenology; the two factors do not necessarily operate in tandem. Insect herbivores show a number of distinct life-history strategies to exploit plants with different growth forms and strategies, which will be differentially affected by climate warming. There are still many challenges facing biologists in predicting and monitoring the impacts of climate change. Future research needs to consider insect herbivore phenotypic and genotypic flexibility, their responses to global change parameters operating in concert, and awareness that some patterns may only become apparent in the longer term. [ABSTRACT FROM AUTHOR]

Composition and density of the soil seed banks, together with seedling emergence in the field, were examined on Svalbard. 1213 soil samples were collected from six drymesic habitats in three regions representing various stages of colonization from bare moraines to full vegetation cover and spanning a range of typical nutrient and thermal regimes. Of the 165 vascular plant species native to Svalbard, 72 were present as mature plants at the study sites and of these 70% germinated seed. Proglacial soil had 12 seedlings per m 2, disturbed Dryas heath 131, intact Dryas heath 91, polar heath 715, thermophilic heath 3113, and a bird cliff 10437 seedlings. Highest seed bank species richness was at the thermophilic heath (26 species). Seedlings of 27 species emerged in the field, with fewer seedlings in disturbed habitats (60 seedlings per m 2 ) than in intact Dryas heath (142), suggesting that an absence of 'safe sites' limited seedling establishment in disturbed habitats. Measurement of seedling emergence in the field increased awareness of which species are able to germinate naturally. This may be underestimated by up to 31% if greenhouse trials alone are used, owing partly to unsuitability of greenhouse conditions for germination of some species and also to practical limitations of amount of soil sampled. Most thermophilic species failed to germinate and some species present at several sites only germinated from the thermophilic heath seed bank, suggesting that climate constrains recruitment from seeds in the High Arctic. [ABSTRACT FROM AUTHOR]