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1.
Glob Chang Biol ; 26(3): 1155-1169, 2020 03.
Article in English | MEDLINE | ID: mdl-31596997

ABSTRACT

Anthropogenic activities have led to a global decline in biodiversity, and monitoring studies indicate that both insect communities and wetland ecosystems are particularly affected. However, there is a need for long-term data (over centennial or millennial timescales) to better understand natural community dynamics and the processes that govern the observed trends. Chironomids (Insecta: Diptera: Chironomidae) are often the most abundant insects in lake ecosystems, sensitive to environmental change, and, because their larval exoskeleton head capsules preserve well in lake sediments, they provide a unique record of insect community dynamics through time. Here, we provide the results of a metadata analysis of chironomid diversity across a range of spatial and temporal scales. First, we analyse spatial trends in chironomid diversity using Northern Hemispheric data sets overall consisting of 837 lakes. Our results indicate that in most of our data sets, summer temperature (Tjul ) is strongly associated with spatial trends in modern-day chironomid diversity. We observe a strong increase in chironomid alpha diversity with increasing Tjul in regions with present-day Tjul between 2.5 and 14°C. In some areas with Tjul  > 14°C, chironomid diversity stabilizes or declines. Second, we demonstrate that the direction and amplitude of change in alpha diversity in a compilation of subfossil chironomid records spanning the last glacial-interglacial transition (~15,000-11,000 years ago) are similar to those observed in our modern data. A compilation of Holocene records shows that during phases when the amplitude of temperature change was small, site-specific factors had a greater influence on the chironomid fauna obscuring the chironomid diversity-temperature relationship. Our results imply expected overall chironomid diversity increases in colder regions such as the Arctic under sustained global warming, but with complex and not necessarily predictable responses for individual sites.


Subject(s)
Chironomidae , Animals , Arctic Regions , Ecosystem , Insecta , Temperature
2.
Biodivers Data J ; (4): e9559, 2016.
Article in English | MEDLINE | ID: mdl-27932915

ABSTRACT

BACKGROUND: The Natural History Museum, London (NHMUK) has embarked on an ambitious programme to digitise its collections . The first phase of this programme has been to undertake a series of pilot projects that will develop the necessary workflows and infrastructure development needed to support mass digitisation of very large scientific collections. This paper presents the results of one of the pilot projects - iCollections. This project digitised all the lepidopteran specimens usually considered as butterflies, 181,545 specimens representing 89 species from the British Isles and Ireland. The data digitised includes, species name, georeferenced location, collector and collection date - the what, where, who and when of specimen data. In addition, a digital image of each specimen was taken. This paper explains the way the data were obtained and the background to the collections which made up the project. NEW INFORMATION: Specimen-level data associated with British and Irish butterfly specimens have not been available before and the iCollections project has released this valuable resource through the NHM data portal.

3.
J Anim Ecol ; 85(3): 739-48, 2016 05.
Article in English | MEDLINE | ID: mdl-26876243

ABSTRACT

Animals with distinct life stages are often exposed to different temperatures during each stage. Thus, how temperature affects these life stages should be considered for broadly understanding the ecological consequences of climate warming on such species. For example, temperature variation during particular life stages may affect respective change in body size, phenology and geographic range, which have been identified as the "universal" ecological responses to climate change. While each of these responses has been separately documented across a number of species, it is not known whether each response occurs together within a species. The influence of temperature during particular life stages may help explain each of these ecological responses to climate change. Our goal was to determine if monthly temperature variation during particular life stages of a butterfly species can predict respective changes in body size and phenology. We also refer to the literature to assess if temperature variability during the adult stage influences range change over time. Using historical museum collections paired with monthly temperature records, we show that changes in body size and phenology of the univoltine butterfly, Hesperia comma, are partly dependent upon temporal variation in summer temperatures during key stages of their life cycle. June temperatures, which are likely to affect growth rate of the final larval instar, are important for predicting adult body size (for males only; showing a positive relationship with temperature). July temperatures, which are likely to influence the pupal stage, are important for predicting the timing of adult emergence (showing a negative relationship with temperature). Previous studies show that August temperatures, which act on the adult stage, are linked to range change. Our study highlights the importance of considering temperature variation during each life stage over historic time-scales for understanding intraspecific response to climate change. Range edge studies of ectothermic species that have annual life cycles, long time-series occurrence data, and associated temperature records (ideally at monthly resolutions) could be useful model systems for intraspecific tests of the universal ecological responses to climate change and for exploring interactive effects.


Subject(s)
Butterflies/growth & development , Climate Change , Life Cycle Stages/physiology , Temperature , Animals , Body Size , Butterflies/anatomy & histology , Butterflies/physiology , England , Female , Male , Seasons , Wings, Animal/anatomy & histology
4.
Int J Biometeorol ; 58(8): 1749-58, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24429705

ABSTRACT

Museum collections have the potential to provide valuable information on the phenological response of organisms to climate change. This is particularly useful for those species for which few data otherwise exist, but also to extend time series to the period before other observational data are available. To test this potential, we analysed data from 2,630 specimens of four species of British butterflies (Anthocharis cardamines, Hamearis lucina, Polyommatus bellargus and Pyrgus malvae), collected from 1876 to 1999 and stored in the Natural History Museum, London, UK (NHM). In A. cardamines, first-generation P. bellargus and P. malvae, we found that there was a strong significant negative relationship between spring temperature and 10th percentile collection dates, which approximates mean first appearance date, and median collection date, which approximates mean flight date. In all four species, there was a significant negative relationship between the 10th percentile collection date and the length of the collection period, which approximates flight period. In second-generation P. bellargus, these phenological measurements were correlated with summer temperature. We found that the rates of phenological response to temperature, based on NHM data, were similar to, or somewhat greater than, those reported for other organisms based on observational data covering the last 40 years. The lower rate of phenological response, and the significant influence of February rather than March or April temperatures, in recent decades compared with data from earlier in the twentieth century may indicate that early emerging British butterfly species are currently approaching the limits of phenological advancement in response to recent climate warming.


Subject(s)
Butterflies/physiology , Ecosystem , Animals , Museums , Seasons , Temperature , United Kingdom
5.
J Adolesc ; 29(3): 395-405, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16143384

ABSTRACT

Personality traits, self-perceptions, beliefs, and feelings that accompany the Imposter Phenomenon (IP) have been identified in adults but little research with adolescents has been reported. The present research describes data from a sample of 11th and 12th graders in order to examine predictors of IP among adolescents. The participants completed measures of the IP, global self-worth, social support and self-concept. Gender differences were found in correlations between IP and Parent Support, Classmate Support, and Teacher Support. Multiple regression analyses found significant predictors of IP scores for females to be Friend Support, Classmate Support and Dependability. Only Friend Support significantly predicted IP scores for males. The unique variance explained (UVE) by each of the variables was fairly modest, suggesting that the variables are explaining a considerable amount of the same portion of the variance, particularly for females.


Subject(s)
Adolescent Behavior/psychology , Deception , Self Concept , Social Behavior , Adolescent , Culture , Female , Humans , Interpersonal Relations , Male , Sex Factors , Social Support , Surveys and Questionnaires
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