Jeremy A Thomas

University of Oxford | OX · Department of Zoology

The six papers in this Special Issue of Insect Conservation and Diversity are presented as a gedenkschrift honouring ground‐breaking contributions made by the late Graham Elmes towards understanding the biology of Myrmica ants and their social parasites. A common theme is that each research paper contributes new knowledge applicable to the future s...

The link between multi‐host use and host switching in host–parasite interactions is a continuing area of debate. Lycaenid butterflies in the genus Maculinea , for example, exploit societies of different Myrmica ant species across their ranges, but there is only rare evidence that they simultaneously utilise multiple hosts at a local site, even wher...

The range of hosts exploited by a parasite is determined by several factors, including host availability, infectivity and exploitability. Each of these can be the target of natural selection on both host and parasite, which will determine the local outcome of interactions, and potentially lead to coevolution. However, geographical variation in host...

This review focuses on the main acoustic adaptations that have evolved to enhance social communication in ants. We also describe how other invertebrates mimic these acoustic signals in order to coexist with ants in the case of mutualistic myrmecophiles, or, in the case of social parasites, corrupt them in order to infiltrate ant societies and explo...

Butterflies are better documented and monitored worldwide than any other nonpest taxon of insects ( 1 ). In the United Kingdom alone, volunteer recorders have sampled more than 750,000 km of repeat transects since 1976, equivalent to walking to the Moon and back counting butterflies ( 2 ). Such programs are revealing regional extinctions and popula...

Data S1. Developing a phylogeny of British butterflies (technical details). Table S1. Species' t‐values and co‐efficients from regressions of mean flight date and three‐monthly mean temperatures. Table S2. Temperature range (within‐ and between‐ populations) of data analysed for each species. Table S3. Results from phylogenetic MCMCglmm analysis...

Understanding the chemical cues and gene expressions that mediate herbivore–host-plant and parasite–host interactions can elucidate the ecological costs and benefits accruing to different partners in tight-knit community modules, and may reveal unexpected complexities. We investigated the exploitation of sequential hosts by the phytophagous–predace...

Phenology shifts are the most widely cited examples of the biological impact of climate change, yet there are few assessments of potential effects on the fitness of individual organisms or the persistence of populations. Despite extensive evidence of climate-driven advances in phenological events over recent decades, comparable patterns across spec...

Improved recording of less popular groups, combined with new statistical approaches that compensate for datasets that were hitherto too patchy for quantitative analysis, now make it possible to compare recent trends in the status of UK invertebrates other than butterflies. Using BRC datasets, we analysed changes in status between 1992 and 2012 for...

A cornerstone of conservation is the designation and management of protected areas (PAs): locations often under conservation management containing species of conservation concern, where some development and other detrimental influences are prevented or mitigated. However, the value of PAs for conserving biodiversity in the long term has been questi...

An important factor in reintroductions is the amount of genetic diversity captured in the introduced individuals. Introduced populations are initially small, and thus vulnerable to genetic drift and stochastic events. The level of genetic diversity maintained is important for the long-term persistence of populations and their evolutionary potential...

Conservation of endangered species necessitates a full appreciation of the ecological processes affecting the regulation, limitation, and persistence of populations. These processes are influenced by birth, death, and dispersal events, and characterizing them requires careful accounting of both the deterministic and stochastic processes operating a...

The dramatic recovery of three species of grassland specialist butterfly threatened with extinction at their high latitude range limits in the 1980s has been attributed to two factors: increased grazing on calcareous grassland sites and warmer air temperatures. Both result in the warming of soil surface temperatures, favourable to the larvae of the...

Lepidoptera are one of the four major insect orders. They are scale-winged insects, traditionally divided into three major assemblages: micro-moths, butterflies and macro-moths. Before discussing practical conservation of Lepidoptera, it is necessary to consider their known rates and causes of change, and whether these are representative of other i...

The possession of an efficient communication system and an ability to distinguish between young stages are essential attributes that enable eusocial insects to live in complex integrated societies. Although ants communicate primarily via chemicals, it is increasingly clear that acoustical signals also convey important information, including status,...

An emerging problem in conservation is whether listed morpho-species with broad distributions, yet specialized lifestyles, consist of more than one cryptic species or functionally distinct forms that have different ecological requirements. We describe extreme regional divergence within an iconic endangered butterfly, whose socially parasitic young...

1. Monitoring the abundance of insect populations is increasingly valuable to understand their population dynamics, plan management strategies and assess the attainment of conservation targets. As monitoring is often constrained in time and space, it is important to have a model of the temporal variation in numbers to enable limited field data to b...

Little is known of the population dynamics of long-range insect migrants, and it has been suggested that the annual journeys of billions of nonhardy insects to exploit temperate zones during summer represent a sink from which future generations seldom return (the "Pied Piper" effect). We combine data from entomological radars and ground-based light...

The benefits of protected areas (PAs) for biodiversity have been questioned in the context of climate change because PAs are static, whereas the distributions of species are dynamic. Current PAs may, however, continue to be important if they provide suitable locations for species to colonize at their leading-edge range boundaries, thereby enabling...

Populations at the high latitude edge of species’ geographical ranges are thought to show larger interannual population fluctuations, with subsequent higher local extinction risk, than those within the ‘core’ climatic range. As climate envelopes shift northward under climate warming, however, we would expect populations to show dampened variability...

Twenty-nine butterfly species are listed on the Annexes of the Habitats Directive. To assist everyone who wants or needs to take action for one of these species, we compiled an overview of the habitat requirements and ecology of each species, as well as information on their conservation status in Europe. This was taken from the recent Red List and...

Numerous invertebrates inhabit social insect colonies, including the hoverfly genus Microdon, whose larvae typically live as brood predators. Formica lemani ant colonies apparently endure Microdon mutabilis infections over several years, despite losing a considerable fraction of young, and may even produce more gynes. We present a model for resourc...

Chemical communication plays a major role in the organisation of ant societies, and is mimicked to near perfection by certain large blue (Maculinea) butterflies that parasitise Myrmica ant colonies. The recent discovery of differentiated acoustical communication between different castes of ants, and the fact that this too is mimicked by the butterf...

Recent recordings of the stridulations of Myrmica ants revealed that their queens made distinctive sounds from their workers, although the acoustics of queens and workers, respectively, were the same in different species of Myrmica. Queen recordings induced enhanced protective behavior when played to workers in the one species tested. Larvae and pu...

The purpose of this application, under Article 23.9.3 of the Code, is to conserve the widely used generic name Maculinea Van Eecke, 1915 in its accustomed usage. The name Maculinea Van Eecke, 1915 is threatened by its senior synonym Phengaris Doherty, 1891. It is proposed that Maculinea be given precedence over the other name whenever the two are c...

Few results of research aimed at solving questions arising from butterfly conservation are rigorously tested by manipulating populations and habitats in the field. Some factors common to successful conservation projects are analysed. In most non-migratory species, population density may vary by up to two orders of magnitude between sites or over ti...

Recent recordings of the stridulations of Myrmica ants revealed that their queens made distinctive sounds from their workers, although the acoustics of queens and workers, respectively, were the same in different species of Myrmica. Queen recordings induced enhanced protective behavior when played to workers in the one species tested. Larvae and pu...

Summary The average rate of decline of butterfly species in the British Isles has been high in recent decades, exceeding that of breeding birds or native vascular plants. Nearly a third of species, however, has increased, and several have expanded their ranges northwards. Some clear patterns are evident from these changes. Most losses are attributa...

Rapid, effective communication between colony members is a key attribute that enables ants to live in dominant, fiercely protected societies. Their signals, however, may be mimicked by other insects that coexist as commensals with ants or interact with them as mutualists or social parasites. We consider the role of acoustics in ant communication an...

Bringing Back the Large Blue Flagship endangered species, such as the Large Blue butterfly have driven conservation programs worldwide. However, the Large Blue butterfly ( Maculinea arion ) became extinct in the United Kingdom. The apparent driver of this extinction was a complex set of events documented by Thomas et al. (p. 80 , published online 1...

Maculinea rebeli caterpillars spend their final instar as specific parasites of colonies of the ant Myrmica schencki. This paper describes 14 experiments in which 604 caterpillars were reared with six species of Myrmica. About 40% of caterpillars died during an initial period of integration: survival was significantly greater among the larger cater...

Ants dominate terrestrial ecosystems through living in complex societies whose organization is maintained via sophisticated communication systems. The role of acoustics in information exchange may be underestimated. We show that Myrmica schencki queens generate distinctive sounds that elicit increased benevolent responses from workers, reinforcing...

The effect of weather on the size of British butterfly populations was studied using national weather records and the Butterfly Monitoring Scheme (BMS), a national database that has measured butterfly abundance since 1976. Strong associations between weather and population fluctuations and trends were found in 28 of 31 species studied . The main po...

Butterflies and other insects have declined more rapidly than birds over parts of southwest Europe this century, and early attempts to conserve them often failed. Failure occurred mainly because reserve managers did not cater for three differences in their needs compared with those of vertebrates: (1) Many insects occupy very narrow specific niches...

The myrmecophilous hoverfly, Microdon mutabilis, is listed as a 'Rare' or 'Nationally Notable Species' in UK Red Data Books. As an obligate social parasite, feeding only from ant colonies, its life-style satisfies theoretical conditions under which cryptic speciation is predicted to evolve; namely, strong selection for nonmorphological adaptations...

Caterpillars of the myrmecophilous butterfly Maculinea rebeli showed strong evidence of contest competition when introduced at high densities to laboratory nests of Myrmica ants. This is attributed to the direct feeding of caterpillars by workers, which select a few individuals to nurture when food or ant numbers are limiting. It contrasts with pub...

The larva of the hoverfly Microdon mutabilis is a specialist social parasite of the ant Formica lemani that is adapted to local groups of F. lemani colonies but mal-adapted to colonies of the same species situated only a few hundred meters away. At a study site in Ireland, F. lemani shares its habitat with four other ant species. All nest under sto...

Larvae of Maculinea alcon and M. rebeli are unique among Holarctic Lycaenidae in hatching through the base of the eggshell and emerging on the opposite side of the leaf to the egg. This occurs because the exposed upper surfaces of their eggs have exceptionally thick shells. Other species of Maculinea have normal or unusually thin-shelled eggs. It i...

The status, ecology and conservation of butterflies in Europe and Britain are reviewed, as a background to the National Trust's past and future contribution to British conservation. Britain has a poor butterfly fauna by European standards, the main areas of endemism and species richness being in the Alps and southern Europe. To date, the main decli...

Caterpillars of the butterfly Maculinea rebeli develop as parasites inside ant colonies. In intensively studied French populations, about 25% of caterpillars mature within 1 year (fast-developing larvae [FDL]) and the others after 2 years (slow-developing larvae [SDL]); all available evidence indicates that this ratio is under the control of egg-la...

Genetic diversity can benefit social insects by providing variability in immune defences against parasites and pathogens. However, social parasites of ants infest colonies and not individuals, and for them a different relationship between genetic diversity and resistance may exist. Here, we investigate the genetic variation, assessed using up to 12...

The Red Data Book hoverfly species Microdon mutabilis is an extreme specialist that parasitises ant societies. The flies are locally adapted to a single host, Formica lemani, more intimately than was thought possible in host-parasite systems. Microdon egg survival plummeted in F. lemani colonies > 3 km away from the natal nest, from c. 96% to 0% to...

The insects are probably the most hyperdiverse and economically important metazoans on the planet, but there is no consensus on the best way to model the dimensions of their diversity at multiple spatial scales, and the huge amount of information involved hinders data synthesis and the revelation of 'patterns of nature'. Using a sample of more than...

Mowing influences two endangered butterfly species, Maculinea nausithous and Maculinea teleius , directly through egg destruction and larval mortality on the mown plants and indirectly through altering the abundance of their sequential resources in meadows ( Sanguisorba plants for oviposition and early larval development and Myrmica ant nests for l...

We develop a ''case model'' approach to investigate how conservation mea-sures may affect the ecology of a community module, defined as a small number of tightly interacting species. The community module consists of a parasitic butterfly and its two hosts, a plant and an ant. The butterfly Maculinea alcon and its host plant Gentiana pneu-monanthe h...

We employ an empirically motivated ''case model'' approach to investigate the theoretical foundations for the conservation of the endangered butterfly Maculinea arion. Maculinea butterflies have highly specialized larvae that sequentially exploit a plant and an ant species. Our study establishes that M. arion's specialized life cycle, including scr...

These proceedings contain 18 papers that discuss topics on speciation and adaptation; life history, evolution, phenotypic plasticity and genetics; sexual selection and reproductive biology; insect-plant interactions; insect-natural enemy interactions; and social insects. A series of empirical case studies in evolutionary ecology using insects as mo...

Conservative estimates suggest that 50-90% of the existing insect species on Earth have still to be discovered, yet the named insects alone comprise more than half of all known species of organism. With such poor baseline knowledge, monitoring change in insect diversity poses a formidable challenge to scientists and most attempts to generalize invo...

The oviposition sites of the xerophilous ecotype of M. alcon (= "Maculinea rebeli") were surveyed in the managed (transi- tional) zone of the Aggtelek National Park and Biosphere Reserve in Northern Hungary. The M. alcon population is distributed over a territory of about 3 ha. In 2001, habitat reconstruction with selective cutting of shrubs and mo...