Publications by category
Journal articles
Field J (In Press). Brood parasites that care: alternative nesting tactics in a subsocial wasp. The American Naturalist
Field J (In Press). Brood parasites that care: alternative nesting tactics in a subsocial wasp. The American Naturalist
Field J (2023). Description and nesting biology of three new species of neotropical silk wasp (Hymenoptera: Apoidea: Pemphredoninae: Microstigmus). Journal of Natural History, 57(1-4), 1-18.
Bonifacii RL, Field J (2023). Nesting biology and social organisation of a silk wasp (<i>Microstigmus rosae</i>) from the North-West Ecuadorian Choco.
INSECTES SOCIAUX,
70(2), 167-179.
Author URL.
Gruber J, Field J (2022). Male survivorship and the evolution of eusociality in partially bivoltine sweat bees.
PLOS ONE,
17(10), e0276428-e0276428.
Abstract:
Male survivorship and the evolution of eusociality in partially bivoltine sweat bees
Eusociality, where workers typically forfeit their own reproduction to assist their mothers in raising siblings, is a fundamental paradox in evolutionary biology. By sacrificing personal reproduction, helpers pay a significant cost, which must be outweighed by indirect fitness benefits of helping to raise siblings. In 1983, Jon Seger developed a model showing how in the haplodiploid Hymenoptera (ants, wasps and bees), a partially bivoltine life cycle with alternating sex ratios may have promoted the evolution of eusociality. Seger predicted that eusociality would be more likely to evolve in hymenopterans where a foundress produces a male-biased first brood sex ratio and a female-biased second brood. This allows first brood females to capitalize on super-sister relatedness through helping to produce the female-biased second brood. In Seger’s model, the key factor driving alternating sex ratios was that first brood males survive to mate with females of both the second and the first brood, reducing the reproductive value of second brood males. Despite being potentially critical in the evolution of eusociality, however, male survivorship has received little empirical attention. Here, we tested whether first brood males survive across broods in the facultatively eusocial sweat bee Halictus rubicundus. We obtained high estimates of survival and, while recapture rates were low, at least 10% of first brood males survived until the second brood. We provide empirical evidence supporting Seger’s model. Further work, measuring brood sex ratios and comparing abilities of first and second brood males to compete for fertilizations, is required to fully parameterize the model.
Abstract.
Boulton RA, Field J (2022). Sensory plasticity in a socially plastic bee. Journal of Evolutionary Biology, 35(9), 1218-1228.
Price TN, Field J (2022). Sisters doing it for themselves: extensive reproductive plasticity in workers of a primitively eusocial bee.
Behavioral Ecology and Sociobiology,
76(7).
Abstract:
Sisters doing it for themselves: extensive reproductive plasticity in workers of a primitively eusocial bee
. Abstract
. Plasticity is a key trait when an individual’s role in the social environment, and hence its optimum phenotype, fluctuates unpredictably. Plasticity is especially important in primitively eusocial insects where small colony sizes and little morphological caste differentiation mean that individuals may find themselves switching from non-reproductive to reproductive roles. To understand the scope of this plasticity, workers of the primitively eusocial sweat bee Lasioglossum malachurum were experimentally promoted to the reproductive role (worker-queens) and their performance compared with foundress-queens. We focussed on how their developmental trajectory as workers influenced three key traits: group productivity, monopolisation of reproduction, and social control of foraging nest-mates. No significant difference was found between the number of offspring produced by worker-queens and foundress-queens. Genotyping of larvae showed that worker-queens monopolised reproduction in their nests to the same extent as foundress queens. However, non-reproductives foraged less and produced a smaller total offspring biomass when the reproductive was a promoted worker: offspring of worker-queens were all males, which are the cheaper sex to produce. Greater investment in each offspring as the number of foragers increased suggests a limit to both worker-queen and foundress-queen offspring production when a greater quantity of pollen arrives at the nest. The data presented here suggest a remarkable level of plasticity and represent one of the first quantitative studies of worker reproductive plasticity in a non-model primitively eusocial species.
.
. Significance statement
. The ability of workers to take on a reproductive role and produce offspring is expected to relate strongly to the size of their colony. Workers in species with smaller colony sizes should have greater reproductive potential to insure against the death of the queen. We quantified the reproductive plasticity of workers in small colonies of sweat bees by removing the queen and allowing the workers to control the reproductive output of the nest. A single worker then took on the reproductive role and hence prevented her fellow workers from producing offspring of their own. These worker-queens produced as many offspring as control queens, demonstrating remarkable worker plasticity in a primitively eusocial species.
.
Abstract.
Pennell TM, Field J (2021). Split sex ratios and genetic relatedness in a primitively eusocial sweat bee.
Behavioral Ecology and Sociobiology,
75(1).
Abstract:
Split sex ratios and genetic relatedness in a primitively eusocial sweat bee
Abstract: in eusocial Hymenoptera, queens and their helper offspring should favour different sex investment ratios. Queens should prefer a 1:1 investment ratio, as they are equally related to offspring of both sexes (r = 0.5). In contrast, helpers should favour an investment ratio of 3:1 towards the production of female brood. This conflict arises because helpers are more closely related to full sisters (r = 0.75) than brothers (r = 0.25). However, helpers should invest relatively more in male brood if relatedness asymmetry within their colony is reduced. This can occur due to queen replacement after colony orphaning, multiple paternity and the presence of unrelated alien helpers. We analysed an unprecedentedly large number of colonies (n = 109) from a UK population of Lasioglossum malachurum, an obligate eusocial sweat bee, to tease apart the effects of these factors on colony-level investment ratios. We found that multiple paternity, unrelated alien helpers and colony orphaning were all common. Queen-right colonies invested relatively more in females than did orphaned colonies, producing a split sex ratio. However, investment ratios did not change due to multiple paternity or the presence of alien helpers, reducing inclusive fitness pay-offs for helpers. Queen control may also have been important: helpers rarely laid male eggs, and investment in female brood was lower when queens were large relative to their helpers. Genetic relatedness between helpers and the brood that they rear was 0.43 in one year and 0.37 in another year, suggesting that ecological benefits, as well as relatedness benefits, are necessary for the maintenance of helping behaviour. Significance statement: How helping behaviour is maintained in eusocial species is a key topic in evolutionary biology. Colony-level sex investment ratio changes in response to relatedness asymmetries can dramatically influence inclusive fitness benefits for helpers in eusocial Hymenoptera. The extent to which helpers in primitively eusocial colonies can respond adaptively to different sources of variation in relatedness asymmetry is unclear. Using data from 109 colonies of the sweat bee Lasioglossum malachurum, we found that queen loss, but not multiple paternity or the presence of alien helpers, was correlated with colony sex investment ratios. Moreover, we quantified average helper-brood genetic relatedness to test whether it is higher than that predicted under solitary reproduction (r = 0.5). Values equal to and below r = 0.5 suggest that relatedness benefits alone cannot explain the maintenance of helping behaviour. Ecological benefits of group living and/or coercion must also contribute.
Abstract.
Field J, Gonzalez-Voyer A, Boulton RA (2020). The evolution of parental care strategies in subsocial wasps.
Behavioral Ecology and Sociobiology,
74(6).
Abstract:
The evolution of parental care strategies in subsocial wasps
. Abstract
. Insect parental care strategies are particularly diverse, and prolonged association between parents and offspring may be a key precursor to the evolution of complex social traits. Macroevolutionary patterns remain obscure, however, due to the few rigorous phylogenetic analyses. The subsocial sphecid wasps are a useful group in which to study parental care because of the diverse range of strategies they exhibit. These strategies range from placing a single prey item in a pre-existing cavity to mass provisioning a pre-built nest, through to complex progressive provisioning where a female feeds larvae in different nests simultaneously as they grow. We show that this diversity stems from multiple independent transitions between states. The strategies we focus on were previously thought of in terms of a stepping-stone model in which complexity increases during evolution, ending with progressive provisioning which is a likely precursor to eusociality. We find that evolution has not always followed this model: reverse transitions are common, and the ancestral state is the most flexible rather than the simplest strategy. Progressive provisioning has evolved several times independently, but transitions away from it appear rare. We discuss the possibility that ancestral plasticity has played a role in the evolution of extended parental care.
.
. Significance statement
. Parental care behaviour leads to prolonged associations between parents and offspring, which is thought to drive the evolution of social living. Despite the importance of insect parental care for shaping the evolution of sociality, relatively few studies have attempted to reconstruct how different strategies evolve in the insects. In this study, we use phylogenetic methods to reconstruct the evolution of the diverse parental care strategies exhibited by the subsocial digger wasps (Sphecidae). Contrary to expectations, we show that parental care in this group has not increased in complexity over evolutionary time. We find that the ancestral state is not the simplest, but may be the most flexible strategy. We suggest that this flexible ancestral strategy may have allowed rapid response to changing environmental conditions which might explain the diversity in parental care strategies that we see in the digger wasps today.
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Abstract.
Field JP, Couchoux C (2019). Parental manipulation of offspring size in social groups: a test using
paper wasps. Behavioral Ecology and Sociobiology
Field JP, Parsons P, Grinsted L (2019). Partner choice correlates with fine scale kin structuring in the paper wasp Polistes dominula. PLoS ONE
Field J, Toyoizumi H (2019). The evolution of eusociality: no risk‐return tradeoff but the ecology matters.
Ecology Letters,
23(3), 518-526.
Abstract:
The evolution of eusociality: no risk‐return tradeoff but the ecology matters
AbstractThe origin of eusociality in the Hymenoptera is a question of major interest. Theory has tended to focus on genetic relatedness, but ecology can be just as important a determinant of whether eusociality evolves. Using the model of Fu et al. (2015), we show how ecological assumptions critically affect the conclusions drawn. Fu et al. inferred that eusociality rarely evolves because it faces a fundamental ‘risk‐return tradeoff’. The intuitive logic was that worker production represents an opportunity cost because it delays realising a reproductive payoff. However, making empirically justified assumptions that (1) workers take over egg‐laying following queen death and (2) productivity increases gradually with each additional worker, we find that the risk‐return tradeoff disappears. We then survey Hymenoptera with more specialised morphological castes, and show how the interaction between two common features of eusociality – saturating birth rates and group size‐dependent helping decisions – can determine whether eusociality outperforms other strategies.
Abstract.
Field JP, Pennell TM, Holman L, Morrow EH (2018). Building a new research framework for social evolution: intralocus caste antagonism. Biological Reviews
Field JP, Accleton C, Foster W (2018). Crozier’s effect and the acceptance of intraspecific brood parasites. Current Biology, 28, 3267-3272.
Davison PJ, Field J (2018). Environmental barriers to sociality in an obligate eusocial sweat bee. Insectes Sociaux, 65(4), 549-559.
Field JP, Davison P (2018). Limited social plasticity in the socially polymorphic sweat bee Lasioglossum calceatum. Behavioral Ecology and Sociobiology, 72, 56-56.
Field JP, Grinsted L (2018). Predictors of nest growth: diminishing returns for subordinates in the paper wasp Polistes dominula. Behavioral Ecology and Sociobiology, 72, 88-88.
Grinsted L, Field J (2017). Biological markets in cooperative breeders: quantifying outside options.
Proceedings of the Royal Society B: Biological Sciences,
284(1856), 20170904-20170904.
Abstract:
Biological markets in cooperative breeders: quantifying outside options
. A major aim in evolutionary biology is to understand altruistic help and reproductive partitioning in cooperative societies, where subordinate helpers forego reproduction to rear dominant breeders' offspring. Traditional models of cooperation in these societies typically make a key assumption: that the only alternative to staying and helping is solitary breeding, an often unfeasible task. Using large-scale field experiments on paper wasps (
. Polistes dominula
. ), we show that individuals have high-quality alternative nesting options available that offer fitness payoffs just as high as their actual chosen options, far exceeding payoffs from solitary breeding. Furthermore, joiners could not easily be replaced if they were removed experimentally, suggesting that it may be costly for dominants to reject them. Our results have implications for expected payoff distributions for cooperating individuals, and suggest that biological market theory, which incorporates partner choice and competition for partners, is necessary to understand helping behaviour in societies like that of
. P. dominula
. Traditional models are likely to overestimate the incentive to stay and help, and therefore the amount of help provided, and may underestimate the size of reproductive concession required to retain subordinates. These findings are relevant for a wide range of cooperative breeders where there is dispersal between social groups.
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Abstract.
Parsons PJ, Couchoux C, Horsburgh GJ, Dawson DA, Field J (2017). Identification of 24 new microsatellite loci in the sweat bee Lasioglossum malachurum (Hymenoptera: Halictidae).
BMC Res Notes,
10(1).
Abstract:
Identification of 24 new microsatellite loci in the sweat bee Lasioglossum malachurum (Hymenoptera: Halictidae).
OBJECTIVE: the objective here is to identify highly polymorphic microsatellite loci for the Palaearctic sweat bee Lasioglossum malachurum. Sweat bees (Hymenoptera: Halictidae) are widespread pollinators that exhibit an unusually large range of social behaviours from non-social, where each female nests alone, to eusocial, where a single queen reproduces while the other members of the colony help to rear her offspring. They thus represent excellent models for understanding social evolution. RESULTS: 24 new microsatellite loci were successfully optimized. When amplified across 23-40 unrelated females, the number of alleles per locus ranged from 3 to 17 and the observed heterozygosities 0.45 to 0.95. Only one locus showed evidence of significant deviation from Hardy-Weinberg equilibrium. No evidence of linkage disequilibrium was found. These 24 loci will enable researchers to gain greater understanding of colony relationships within this species, an important model for the study of eusociality. Furthermore, 22 of the same loci were also successfully amplified in L. calceatum, suggesting that these loci may be useful for investigating the ecology and evolution of sweat bees in general.
Abstract.
Author URL.
Grinsted L, Field J (2017). Market forces influence helping behaviour in cooperatively breeding paper wasps. Nature Communications, 8
DAVISON PJ, FIELD J (2017). Season length, body size, and social polymorphism: size clines but not saw tooth clines in sweat bees.
Ecological Entomology,
42(6), 768-776.
Abstract:
Season length, body size, and social polymorphism: size clines but not saw tooth clines in sweat bees
1. Annual insects are predicted to grow larger where the growing season is longer. However, transitions from one to two generations per year can occur when the season becomes sufficiently long, and are predicted to result in a sharp decrease in body size because available development time is halved. The potential for resulting saw‐tooth clines has been investigated only in solitary taxa with free‐living larvae.2. Size clines were investigated in two socially polymorphic sweat bees (Halictidae): transitions between solitary and social nesting occur along gradients of increasing season length, characterised by the absence or presence of workers and offspring that are individually mass provisioned by adults. How the body size changes with season length was examined, and whether transitions in social phenotype generate saw‐tooth size clines. We measured Lasioglossum calceatum and Halictus rubicundus nest foundresses originating from more than 1000 km of latitude, encompassing the transition between social and solitary nesting.3. Using satellite‐collected temperature data to estimate season length, it was shown that both species were largest where the season was longest. Body size increased linearly with season length in L. calceatum and non‐linearly in H. rubicundus but the existence of saw‐tooth clines was not supported.4. The present results suggest that because the amount of food consumed by offspring during development is determined by adults, environmental and social influences on the provisioning strategies of adult bees may be more important factors than available feeding time in determining offspring body size in socially polymorphic sweat bees.
Abstract.
Schürch R, Accleton C, Field J (2016). Consequences of a warming climate for social organisation in sweat bees. Behavioral Ecology and Sociobiology, 70(8), 1131-1139.
Field J, Leadbeater E (2016). Cooperation between non-relatives in a primitively eusocial paper wasp. <i>Polistes dominula</i>.
Philosophical Transactions of the Royal Society B: Biological Sciences,
371(1687), 20150093-20150093.
Abstract:
Cooperation between non-relatives in a primitively eusocial paper wasp. Polistes dominula
. In cooperatively breeding vertebrates, the existence of individuals that help to raise the offspring of non-relatives is well established, but unrelated helpers are less well known in the social insects. Eusocial insect groups overwhelmingly consist of close relatives, so populations where unrelated helpers are common are intriguing. Here, we focus on
. Polistes dominula—
. the best-studied primitively eusocial wasp, and a species in which nesting with non-relatives is not only present but frequent. We address two major questions: why individuals should choose to nest with non-relatives, and why such individuals participate in the costly rearing of unrelated offspring.
. Polistes dominula
. foundresses produce more offspring of their own as subordinates than when they nest independently, providing a potential explanation for co-founding by non-relatives. There is some evidence that unrelated subordinates tailor their behaviour towards direct fitness, while the role of recognition errors in generating unrelated co-foundresses is less clear. Remarkably, the remote but potentially highly rewarding chance of inheriting the dominant position appears to strongly influence behaviour, suggesting that primitively eusocial insects may have much more in common with their social vertebrate counterparts than has commonly been thought.
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Abstract.
Green JP, Almond EJ, Williamson J, Field J (2016). Regulation of host colony activity by the social parasite Polistes semenowi. Insectes Sociaux, 63(3), 385-393.
Davison PJ, Field J (2016). Social polymorphism in the sweat bee Lasioglossum (Evylaeus) calceatum. Insectes Sociaux, 63(2), 327-338.
Field J, Shreeves G, Kennedy M, Brace S, Gilbert JDJ (2015). Sex-biased parental care and sexual size dimorphism in a provisioning arthropod. Behavioral Ecology and Sociobiology, 69(12), 1897-1906.
Donaldson L, Thompson FJ, Field J, Cant MA (2014). Do paper wasps negotiate over helping effort?.
Behavioral Ecology,
25(1), 88-94.
Abstract:
Do paper wasps negotiate over helping effort?
Recent theory and empirical studies of avian biparental systems suggest that animals resolve conflict over parental care via a process of behavioral negotiation or "rules for responding." Less is known, however, about whether negotiation over helping effort occurs in cooperatively breeding animal societies or whether behavioral negotiation requires a relatively large brain. In this study, we tested whether negotiation over help occurs in a social insect, the paper wasp Polistes dominulus, by recording individual responses to both observed and experimentally induced foraging returns by other group members. In our experiments, we manipulated food delivery to the nest in 2 ways: 1) by catching departing foragers and giving them larval food to take back to the nest and 2) by giving larval food directly to wasps on the nest, which they then fed to larvae, so increasing food delivery independently of helper effort. We found no evidence from Experiment 1 that helpers adjusted their own foraging effort according to the foraging effort of other group members. However, when food was provided directly to the nest, wasps did respond by reducing their own foraging effort. One interpretation of this result is that paper wasp helpers adjust their helping effort according to the level of offspring need rather than the work rate of other helpers. Negotiation based on indicators of demand rather than work rate is a likely mechanism to resolve conflict over investment in teams where helpers cannot observe each other's work rate directly, as is commonly the case in insect and vertebrate societies. © the Author 2013.
Abstract.
Thompson FJ, Donaldson L, Johnstone RA, Field J, Cant MA (2014). Dominant aggression as a deterrent signal in paper wasps. Behavioral Ecology, 25(4), 706-715.
Toyoizumi H, Field J (2014). Dynamics of social queues. Journal of Theoretical Biology, 346, 16-22.
Toyoizumi H, Field J (2014). Reduction of Foraging Work and Cooperative Breeding. Acta Biotheoretica, 62(2), 123-132.
Green JP, Cant MA, Field J (2014). Using social parasitism to test reproductive skew models in a primitively eusocial wasp.
Proceedings. Biological sciences,
281(1789).
Abstract:
Using social parasitism to test reproductive skew models in a primitively eusocial wasp.
Remarkable variation exists in the distribution of reproduction (skew) among members of cooperatively breeding groups, both within and between species. Reproductive skew theory has provided an important framework for understanding this variation. In the primitively eusocial Hymenoptera, two models have been routinely tested: concessions models, which assume complete control of reproduction by a dominant individual, and tug-of-war models, which assume on-going competition among group members over reproduction. Current data provide little support for either model, but uncertainty about the ability of individuals to detect genetic relatedness and difficulties in identifying traits conferring competitive ability mean that the relative importance of concessions versus tug-of-war remains unresolved. Here, we suggest that the use of social parasitism to generate meaningful variation in key social variables represents a valuable opportunity to explore the mechanisms underpinning reproductive skew within the social Hymenoptera. We present a direct test of concessions and tug-of-war models in the paper wasp Polistes dominulus by exploiting pronounced changes in relatedness and power structures that occur following replacement of the dominant by a congeneric social parasite. Comparisons of skew in parasitized and unparasitized colonies are consistent with a tug-of-war over reproduction within P. dominulus groups, but provide no evidence for reproductive concessions.
Abstract.
Leadbeater E, Dapporto L, Turillazzi S, Field J (2013). Available kin recognition cues may explain why wasp behavior reflects relatedness to nest mates. Behavioral Ecology, 25(2), 344-351.
Lucas ER, Field J (2013). Caste determination through mating in primitively eusocial societies. Journal of Theoretical Biology, 335, 31-39.
Green JP, Leadbeater E, Carruthers JM, Rosser NS, Lucas ER, Field J (2013). Clypeal patterning in the paper wasp Polistes dominulus: no evidence of adaptive value in the wild. Behavioral Ecology, 24(3), 623-633.
Toyoizumi H, Field J (2012). Analysis of the dynamics of social queues by quasi-birth-and-death processes (abstract only). ACM SIGMETRICS Performance Evaluation Review, 39(4), 29-30.
Field J, Paxton R, Soro A, Craze P, Bridge C (2012). Body size, demography and foraging in a socially plastic sweat bee: a common garden experiment. Behavioral Ecology and Sociobiology, 66(5), 743-756.
Lengronne T, Leadbeater E, Patalano S, Dreier S, Field J, Sumner S, Keller L (2012). Little effect of seasonal constraints on population genetic structure in eusocial paper wasps. Ecology and Evolution, 2(10), 2615-2624.
Johnstone RA, Cant MA, Field J (2012). Sex-biased dispersal, haplodiploidy and the evolution of helping in social insects.
Proc Biol Sci,
279(1729), 787-793.
Abstract:
Sex-biased dispersal, haplodiploidy and the evolution of helping in social insects.
In his famous haplodiploidy hypothesis, W. D. Hamilton proposed that high sister-sister relatedness facilitates the evolution of kin-selected reproductive altruism among Hymenopteran females. Subsequent analyses, however, suggested that haplodiploidy cannot promote altruism unless altruists capitalize on relatedness asymmetries by helping to raise offspring whose sex ratio is more female-biased than the population at large. Here, we show that haplodiploidy is in fact more favourable than is diploidy to the evolution of reproductive altruism on the part of females, provided only that dispersal is male-biased (no sex-ratio bias or active kin discrimination is required). The effect is strong, and applies to the evolution both of sterile female helpers and of helping among breeding females. Moreover, a review of existing data suggests that female philopatry and non-local mating are widespread among nest-building Hymenoptera. We thus conclude that Hamilton was correct in his claim that 'family relationships in the Hymenoptera are potentially very favourable to the evolution of reproductive altruism'.
Abstract.
Author URL.
Green JP, Rose C, Field J (2012). The Role of Climatic Factors in the Expression of an Intrasexual Signal in the Paper Wasp <i><scp>P</scp>olistes dominulus</i>.
Ethology,
118(8), 766-774.
Abstract:
The Role of Climatic Factors in the Expression of an Intrasexual Signal in the Paper Wasp Polistes dominulus
AbstractWithin a species, variation in the use of sexual signals is observed between different populations. For intersexual traits, differences in the environmental conditions experienced by populations can play an important role in driving variation in male ornaments and female preferences. However, little is known about the factors maintaining variation in intrasexual traits used in competition. In this study, we investigate the role of climatic conditions in maintaining variation in the expression of an intrasexual signal in the paper wasp Polistes dominulus. The results of an experiment in which pupae were housed under different temperature and humidity conditions revealed a strong effect of temperature during pupal development on the expression of the signal. Furthermore, a comparison of survival and body weight between wasps reared at different temperatures indicates that signal expression exhibits phenotypic plasticity in response to developmental temperature. The effect of temperature on signal expression is consistent with patterns of signal expression observed across populations in the wild and suggests that climatic conditions may act to constrain signal expression in some populations but not in others, driving variation in signal use within P. dominulus. Environmental conditions may therefore be important in defining the scope for intrasexual signalling in animal populations and, in doing so, may play a role in maintaining variation in intrasexual traits in the face of sexual selection.
Abstract.
FIELD J, OHL M, KENNEDY M (2011). A molecular phylogeny for digger wasps in the tribe Ammophilini (Hymenoptera, Apoidea, Sphecidae). Systematic Entomology, 36(4), 732-740.
Lucas ER, Field J (2011). Active and effective nest defence by males in a social apoid wasp. Behavioral Ecology and Sociobiology, 65(8), 1499-1504.
Green JP, Field J (2011). Assessment between species: information gathering in usurpation contests between a paper wasp and its social parasite. Animal Behaviour, 81(6), 1263-1269.
Lucas ER, Field J (2011). Assured fitness returns in a social wasp with no worker caste.
Proceedings of the Royal Society B: Biological Sciences,
278(1720), 2991-2995.
Abstract:
Assured fitness returns in a social wasp with no worker caste
. The theory of assured fitness returns proposes that individuals nesting in groups gain fitness benefits from effort expended in brood-rearing, even if they die before the young that they have raised reach independence. These benefits, however, require that surviving nest-mates take up the task of rearing these young. It has been suggested that assured fitness returns could have favoured group nesting even at the origin of sociality (that is, in species without a dedicated worker caste). We show that experimentally orphaned brood of the apoid wasp
. Microstigmus nigrophthalmus
. continue to be provisioned by surviving adults for at least two weeks after the orphaning. This was the case for brood of both sexes. There was no evidence that naturally orphaned offspring received less food than those that still had mothers in the nest. Assured fitness returns can therefore represent a real benefit to nesting in groups, even in species without a dedicated worker caste.
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Abstract.
Zanette LRS, Field J (2011). Founders versus joiners: group formation in the paper wasp Polistes dominulus. Animal Behaviour, 82(4), 699-705.
Abbot P, Abe J, Alcock J, Alizon S, Alpedrinha JAC, Andersson M, Andre J-B, van Baalen M, Balloux F, Balshine S, et al (2011). Inclusive fitness theory and eusociality.
Nature,
471(7339), E1-E4.
Abstract:
Inclusive fitness theory and eusociality.
Arising from M. A. Nowak, C. E. Tarnita & E. O. Wilson 466, 1057-1062 (2010); Nowak et al. reply. Nowak et al. argue that inclusive fitness theory has been of little value in explaining the natural world, and that it has led to negligible progress in explaining the evolution of eusociality. However, we believe that their arguments are based upon a misunderstanding of evolutionary theory and a misrepresentation of the empirical literature. We will focus our comments on three general issues.
Abstract.
Author URL.
Green JP, Field J (2011). Interpopulation variation in status signalling in the paper wasp Polistes dominulus. Animal Behaviour, 81(1), 205-209.
Leadbeater E, Carruthers JM, Green JP, Rosser NS, Field J (2011). Nest Inheritance is the Missing Source of Direct Fitness in a Primitively Eusocial Insect.
Science,
333(6044), 874-876.
Abstract:
Nest Inheritance is the Missing Source of Direct Fitness in a Primitively Eusocial Insect
. Fitness benefits from the inheritance of breeding resources may explain why
. Polistes
. wasps cooperate with nonrelatives.
.
Abstract.
Lucas ER, Martins RP, Field J (2011). Reproductive skew is highly variable and correlated with genetic relatedness in a social apoid wasp. Behavioral Ecology, 22(2), 337-344.
Cronin AL, Bridge C, Field J (2010). Climatic correlates of temporal demographic variation in the tropical hover wasp Liostenogaster flavolineata. Insectes Sociaux, 58(1), 23-29.
Field J, Paxton RJ, Soro A, Bridge C (2010). Cryptic Plasticity Underlies a Major Evolutionary Transition. Current Biology, 20(22), 2028-2031.
SORO A, FIELD J, BRIDGE C, CARDINAL SC, PAXTON RJ (2010). Genetic differentiation across the social transition in a socially polymorphic sweat bee, Halictus rubicundus. Molecular Ecology, 19(16), 3351-3363.
Lucas ER, Martins RP, Zanette LRS, Field J (2010). Social and genetic structure in colonies of the social wasp Microstigmus nigrophthalmus. Insectes Sociaux, 58(1), 107-114.
Leadbeater E, Carruthers JM, Green JP, van Heusden J, Field J (2010). Unrelated Helpers in a Primitively Eusocial Wasp: is Helping Tailored Towards Direct Fitness?. PLoS ONE, 5(8), e11997-e11997.
LUCAS ER, HORSBURGH GJ, DAWSON DA, FIELD J (2009). Characterization of microsatellite loci isolated from the wasp, <i>Microstigmus nigrophthalmus</i> (Hymenoptera).
Molecular Ecology Resources,
9(6), 1492-1497.
Abstract:
Characterization of microsatellite loci isolated from the wasp, Microstigmus nigrophthalmus (Hymenoptera)
AbstractFifty‐two microsatellite loci were characterized in 22–31 unrelated females of the wasp (Microstigmus nigrophthalmus) collected from the Mata do Paraiso, Viçosa, M.G. Brazil. Fifty‐one of these loci were developed from a microsatellite‐enriched genomic library derived from M. nigrophthalmus and one was derived from the wasp, Ormyrus nitidulus. The genus Microstigmus represents an independent origin of social behaviour in the Hymenoptera and is thus of great potential in the study of social evolution.
Abstract.
Zanette L, Field J (2009). Cues, concessions, and inheritance: dominance hierarchies in the paper wasp Polistes dominulus. Behavioral Ecology, 20(4), 773-780.
Field J, Cant MA (2009). Social stability and helping in small animal societies.
Philos Trans R Soc Lond B Biol Sci,
364(1533), 3181-3189.
Abstract:
Social stability and helping in small animal societies.
In primitively eusocial societies, all individuals can potentially reproduce independently. The key fact that we focus on in this paper is that individuals in such societies instead often queue to inherit breeding positions. Queuing leads to systematic differences in expected future fitness. We first discuss the implications this has for variation in behaviour. For example, because helpers nearer to the front of the queue have more to lose, they should work less hard to rear the dominant's offspring. However, higher rankers may be more aggressive than low rankers, even if they risk injury in the process, if aggression functions to maintain or enhance queue position. Second, we discuss how queuing rules may be enforced through hidden threats that rarely have to be carried out. In fishes, rule breakers face the threat of eviction from the group. In contrast, subordinate paper wasps are not injured or evicted during escalated challenges against the dominant, perhaps because they are more valuable to the dominant. We discuss evidence that paper-wasp dominants avoid escalated conflicts by ceding reproduction to subordinates. Queuing rules appear usually to be enforced by individuals adjacent in the queue rather than by dominants. Further manipulative studies are required to reveal mechanisms underlying queue stability and to elucidate what determines queue position in the first place.
Abstract.
Author URL.
Paxton RJ, Ayasse M, Field J, Soro A (2008). Complex sociogenetic organization and reproductive skew in a primitively eusocial sweat bee, Lasioglossum malachurum, as revealed by microsatellites. Molecular Ecology, 11(11), 2405-2416.
Zanette LRS, Field J (2008). Genetic relatedness in early associations of Polistes dominulus : from related to unrelated helpers. Molecular Ecology, 17(11), 2590-2597.
Field J, Cant MA (2007). Direct fitness, reciprocity and helping: a perspective from primitively eusocial wasps.
Behav Processes,
76(2), 160-162.
Author URL.
Shreeves G, Field J (2007). Parental care and sexual size dimorphism in wasps and bees. Behavioral Ecology and Sociobiology, 62(5), 843-852.
Bridge C, Field J (2007). Queuing for dominance: gerontocracy and queue-jumping in the hover wasp Liostenogaster flavolineata. Behavioral Ecology and Sociobiology, 61(8), 1253-1259.
Cronin A, Field J (2007). Social aggression in an age-dependent dominance hierarchy. Behaviour, 144(7), 753-765.
Bolton A, Sumner S, Shreeves G, Casiraghi M, Field J (2006). Colony genetic structure in a facultatively eusocial hover wasp. Behavioral Ecology, 17(6), 873-880.
Field J, Turner E, Fayle T, Foster WA (2006). Costs of egg-laying and offspring provisioning: multifaceted parental investment in a digger wasp.
Proceedings of the Royal Society B: Biological Sciences,
274(1608), 445-451.
Abstract:
Costs of egg-laying and offspring provisioning: multifaceted parental investment in a digger wasp
. Nest-building Hymenoptera have been a major testing ground for theories of parental investment and sex allocation. Investment has usually been estimated by the likely costs of offspring provisioning, ignoring other aspects of parental care. Using three experimental treatments, we estimated the costs of egg-laying and provisioning separately under field conditions in a digger wasp
. Ammophila pubescens
. In one treatment, we increased the provisioning effort required per offspring by removing alternate prey items as they were brought to the nest. In two other treatments, we reduced parental effort by either preventing females from provisioning alternate nests or preventing them from both ovipositing and provisioning. Our results indicate that both egg-laying and provisioning represent significant costs of reproduction, expressed as differences in productivity but not survival. A trade-off-based model suggests that other components of parental care such as nest initiation may also represent significant costs. Costs of egg production and nest initiation are probably similar for male and female offspring, so that taking them into account leads to a less male-biased expected sex ratio. Mothers compensated only partially for prey removal in terms of the total provisions they gave to individual offspring.
.
Abstract.
Cant MA, English S, Reeve HK, Field J (2006). Escalated conflict in a social hierarchy.
Proc Biol Sci,
273(1604), 2977-2984.
Abstract:
Escalated conflict in a social hierarchy.
Animals that live in cooperative societies form hierarchies in which dominant individuals reap disproportionate benefits from group cooperation. The stability of these societies requires subordinates to accept their inferior status rather than engage in escalated conflict with dominants over rank. Applying the logic of animal contests to these cases predicts that escalated conflict is more likely where subordinates are reproductively suppressed, where group productivity is high, relatedness is low, and where subordinates are relatively strong. We tested these four predictions in the field on co-foundress associations of the paper wasp Polistes dominulus by inducing contests over dominance rank experimentally. Subordinates with lower levels of ovarian development, and those in larger, more productive groups, were more likely to escalate in conflict with their dominant, as predicted. Neither genetic relatedness nor relative body size had significant effects on the probability of escalation. The original dominant emerged as the winner in all except one escalated contest. The results provide the first evidence that reproductive suppression of subordinates increases the threat of escalated conflict, and hence that reproductive sharing can promote stability of the dominant-subordinate relationship.
Abstract.
Author URL.
Field J, Cronin A, Bridge C (2006). Future fitness and helping in social queues. Nature, 441(7090), 214-217.
Cant MA, Llop JB, Field J (2006). Individual variation in social aggression and the probability of inheritance: theory and a field test.
The American naturalist,
167(6), 837-852.
Abstract:
Individual variation in social aggression and the probability of inheritance: theory and a field test.
Recent theory suggests that much of the wide variation in individual behavior that exists within cooperative animal societies can be explained by variation in the future direct component of fitness, or the probability of inheritance. Here we develop two models to explore the effect of variation in future fitness on social aggression. The models predict that rates of aggression will be highest toward the front of the queue to inherit and will be higher in larger, more productive groups. A third prediction is that, in seasonal animals, aggression will increase as the time available to inherit the breeding position runs out. We tested these predictions using a model social species, the paper wasp Polistes dominulus. We found that rates of both aggressive "displays" (aimed at individuals of lower rank) and aggressive "tests" (aimed at individuals of higher rank) decreased down the hierarchy, as predicted by our models. The only other significant factor affecting aggression rates was date, with more aggression observed later in the season, also as predicted. Variation in future fitness due to inheritance rank is the hidden factor accounting for much of the variation in aggressiveness among apparently equivalent individuals in this species.
Abstract.
Cronin AL, Field J (2006). Rank and colony defense against conspecifics in a facultatively eusocial hover wasp. Behavioral Ecology, 18(2), 331-336.
Mesterton-Gibbons M, Hardy ICW, Field J (2006). The effect of differential survivorship on the stability of reproductive queueing. Journal of Theoretical Biology, 242(3), 699-712.
Field, J. (2005). Helping effort in a dominance hierarchy. Behavioral Ecology, 16, 708-715
Sumner S, Field J (2005). Highly polymorphic microsatellite loci in the facultatively eusocial hover wasp, Liostenogaster flavolineata and cross‐species amplification. Molecular Ecology Resources, 1(4), 229-231.
Field J (2005). The evolution of progressive provisioning. Behavioral Ecology, 16(4), 770-778.
Field J, Brace S (2004). Pre-social benefits of extended parental care. Nature, 428(6983), 650-652.
Shreeves G, Cant MA, Bolton A, Field J (2003). Insurance-based advantages for subordinate co-foundresses in a temperate paper wasp.
Proc Biol Sci,
270(1524), 1617-1622.
Abstract:
Insurance-based advantages for subordinate co-foundresses in a temperate paper wasp.
Recent explanations for the evolution of eusociality, focusing more on costs and benefits than relatedness, are largely untested. We validate one such model by showing that helpers in foundress groups of the paper wasp Polistes dominulus benefit from an insurance-based mechanism known as Assured Fitness Returns (AFRs). Experimental helper removals left remaining group members with more offspring than they would normally rear. Reduced groups succeeded in preserving the dead helpers' investment by rearing these extra offspring, even when helper removals occurred long before worker emergence. While helpers clearly gained from AFRs, offspring of lone foundresses failed after foundress death, so that AFRs represent a true advantage for helpers. Smaller, less valuable offspring were probably sacrificed to feed larger offspring, but reduced groups did not preferentially attract joiners or increase their foraging effort to compensate for their smaller workforce. We failed to detect a second insurance-based advantage, Survivorship Insurance, in which larger groups are less likely to fail than smaller groups. We suggest that through their use of small offspring as a food store to cope with temporary shortages, wasps may be less susceptible than vertebrates to offspring failure following the death of group members.
Abstract.
Author URL.
Paxton RJ, Arévalo E, Field J (2003). Microsatellite loci for the eusocial Lasioglossum malachurum and other sweat bees (Hymenoptera, Halictidae). Molecular Ecology Resources, 3(1), 82-84.
Shreeves G, Field J (2002). Group Size and Direct Fitness in Social Queues. The American Naturalist, 159(1), 81-95.
Sumner S, Casiraghi M, Foster W, Field J (2002). High reproductive skew in tropical hover wasps. Proceedings of the Royal Society B, 269(1487), 179-186.
Cant MA, Field J (2001). Helping effort and future fitness in cooperation animal societies.
Proc Biol Sci,
268(1479), 1959-1964.
Abstract:
Helping effort and future fitness in cooperation animal societies.
Little attention has been paid to a conspicuous and universal feature of animal societies: the variation between individuals in helping effort. Here, we develop a multiplayer kin-selection model that assumes that subordinates face a trade-off because current investment in help reduces their own future reproductive success. The model makes two predictions: (i) subordinates will work less hard the closer they are to inheriting breeding status; and (ii) for a given dominance rank, subordinates will work less hard in larger groups. The second prediction reflects the larger pay-off from inheriting a larger group. Both predictions were tested through a field experiment on the paper wasp Polistes dominulus. First, we measured an index of helping effort among subordinates, then we removed successive dominants to reveal the inheritance ranks of the subordinates: their positions in the queue to inherit dominance. We found that both inheritance rank and group size had significant effects on helping effort, in the manner predicted by our model. The close match between our theoretical and empirical results suggests that individuals adjust their helping effort according to their expected future reproductive success. This relationship has probably remained hidden in previous studies that have focused on variation in genetic relatedness.
Abstract.
Author URL.
Field J, Shreeves G, Sumner S, Casiraghi M (2000). Insurance-based advantage to helpers in a tropical hover wasp. Nature, 404(6780), 869-871.
Field J, Shreeves G, Sumner S (1999). Group size, queuing and helping decisions in facultatively eusocial hover wasps. Behavioral Ecology and Sociobiology, 45(5), 378-385.
FIELD J, FOSTER W (1999). Helping behaviour in facultatively eusocial hover wasps: an experimental test of the subfertility hypothesis. Animal Behaviour, 57(3), 633-636.
Field J, Foster W, Shreeves G, Sumner S (1998). Ecological constraints on independent nesting in facultatively eusocial hover wasps. Proceedings of the Royal Society B, 265(1400), 973-977.
Chapters
Field J (2021). Hover Wasps (Stenogastrinae). In (Ed) Encyclopedia of Social Insects, Springer Nature, 500-504.
Field J (2019). Hover Wasps (Stenogastrinae). In (Ed) Encyclopedia of Social Insects, Springer Nature, 1-5.
Field J, Cant, M.A. (2009). Reproductive skew in primitively eusocial insects: lessons for vertebrates. In Hager R, Jones CB (Eds.)
Reproductive Skew in Vertebrates, Cambridge: Cambridge University Press, 305-334.
Abstract:
Reproductive skew in primitively eusocial insects: lessons for vertebrates.
Abstract.
Publications by year
In Press
Field J (In Press). Brood parasites that care: alternative nesting tactics in a subsocial wasp. The American Naturalist
Field J (In Press). Brood parasites that care: alternative nesting tactics in a subsocial wasp. The American Naturalist
2023
Field J (2023). Description and nesting biology of three new species of neotropical silk wasp (Hymenoptera: Apoidea: Pemphredoninae: Microstigmus). Journal of Natural History, 57(1-4), 1-18.
Bonifacii RL, Field J (2023). Nesting biology and social organisation of a silk wasp (<i>Microstigmus rosae</i>) from the North-West Ecuadorian Choco.
INSECTES SOCIAUX,
70(2), 167-179.
Author URL.
2022
Gruber J, Field J (2022). Male survivorship and the evolution of eusociality in partially bivoltine sweat bees.
PLOS ONE,
17(10), e0276428-e0276428.
Abstract:
Male survivorship and the evolution of eusociality in partially bivoltine sweat bees
Eusociality, where workers typically forfeit their own reproduction to assist their mothers in raising siblings, is a fundamental paradox in evolutionary biology. By sacrificing personal reproduction, helpers pay a significant cost, which must be outweighed by indirect fitness benefits of helping to raise siblings. In 1983, Jon Seger developed a model showing how in the haplodiploid Hymenoptera (ants, wasps and bees), a partially bivoltine life cycle with alternating sex ratios may have promoted the evolution of eusociality. Seger predicted that eusociality would be more likely to evolve in hymenopterans where a foundress produces a male-biased first brood sex ratio and a female-biased second brood. This allows first brood females to capitalize on super-sister relatedness through helping to produce the female-biased second brood. In Seger’s model, the key factor driving alternating sex ratios was that first brood males survive to mate with females of both the second and the first brood, reducing the reproductive value of second brood males. Despite being potentially critical in the evolution of eusociality, however, male survivorship has received little empirical attention. Here, we tested whether first brood males survive across broods in the facultatively eusocial sweat bee Halictus rubicundus. We obtained high estimates of survival and, while recapture rates were low, at least 10% of first brood males survived until the second brood. We provide empirical evidence supporting Seger’s model. Further work, measuring brood sex ratios and comparing abilities of first and second brood males to compete for fertilizations, is required to fully parameterize the model.
Abstract.
Boulton RA, Field J (2022). Sensory plasticity in a socially plastic bee.
Boulton RA, Field J (2022). Sensory plasticity in a socially plastic bee. Journal of Evolutionary Biology, 35(9), 1218-1228.
Price TN, Field J (2022). Sisters doing it for themselves: extensive reproductive plasticity in workers of a primitively eusocial bee.
Behavioral Ecology and Sociobiology,
76(7).
Abstract:
Sisters doing it for themselves: extensive reproductive plasticity in workers of a primitively eusocial bee
. Abstract
. Plasticity is a key trait when an individual’s role in the social environment, and hence its optimum phenotype, fluctuates unpredictably. Plasticity is especially important in primitively eusocial insects where small colony sizes and little morphological caste differentiation mean that individuals may find themselves switching from non-reproductive to reproductive roles. To understand the scope of this plasticity, workers of the primitively eusocial sweat bee Lasioglossum malachurum were experimentally promoted to the reproductive role (worker-queens) and their performance compared with foundress-queens. We focussed on how their developmental trajectory as workers influenced three key traits: group productivity, monopolisation of reproduction, and social control of foraging nest-mates. No significant difference was found between the number of offspring produced by worker-queens and foundress-queens. Genotyping of larvae showed that worker-queens monopolised reproduction in their nests to the same extent as foundress queens. However, non-reproductives foraged less and produced a smaller total offspring biomass when the reproductive was a promoted worker: offspring of worker-queens were all males, which are the cheaper sex to produce. Greater investment in each offspring as the number of foragers increased suggests a limit to both worker-queen and foundress-queen offspring production when a greater quantity of pollen arrives at the nest. The data presented here suggest a remarkable level of plasticity and represent one of the first quantitative studies of worker reproductive plasticity in a non-model primitively eusocial species.
.
. Significance statement
. The ability of workers to take on a reproductive role and produce offspring is expected to relate strongly to the size of their colony. Workers in species with smaller colony sizes should have greater reproductive potential to insure against the death of the queen. We quantified the reproductive plasticity of workers in small colonies of sweat bees by removing the queen and allowing the workers to control the reproductive output of the nest. A single worker then took on the reproductive role and hence prevented her fellow workers from producing offspring of their own. These worker-queens produced as many offspring as control queens, demonstrating remarkable worker plasticity in a primitively eusocial species.
.
Abstract.
2021
Field J (2021). Hover Wasps (Stenogastrinae). In (Ed) Encyclopedia of Social Insects, Springer Nature, 500-504.
Pennell TM, Field J (2021). Split sex ratios and genetic relatedness in a primitively eusocial sweat bee.
Behavioral Ecology and Sociobiology,
75(1).
Abstract:
Split sex ratios and genetic relatedness in a primitively eusocial sweat bee
Abstract: in eusocial Hymenoptera, queens and their helper offspring should favour different sex investment ratios. Queens should prefer a 1:1 investment ratio, as they are equally related to offspring of both sexes (r = 0.5). In contrast, helpers should favour an investment ratio of 3:1 towards the production of female brood. This conflict arises because helpers are more closely related to full sisters (r = 0.75) than brothers (r = 0.25). However, helpers should invest relatively more in male brood if relatedness asymmetry within their colony is reduced. This can occur due to queen replacement after colony orphaning, multiple paternity and the presence of unrelated alien helpers. We analysed an unprecedentedly large number of colonies (n = 109) from a UK population of Lasioglossum malachurum, an obligate eusocial sweat bee, to tease apart the effects of these factors on colony-level investment ratios. We found that multiple paternity, unrelated alien helpers and colony orphaning were all common. Queen-right colonies invested relatively more in females than did orphaned colonies, producing a split sex ratio. However, investment ratios did not change due to multiple paternity or the presence of alien helpers, reducing inclusive fitness pay-offs for helpers. Queen control may also have been important: helpers rarely laid male eggs, and investment in female brood was lower when queens were large relative to their helpers. Genetic relatedness between helpers and the brood that they rear was 0.43 in one year and 0.37 in another year, suggesting that ecological benefits, as well as relatedness benefits, are necessary for the maintenance of helping behaviour. Significance statement: How helping behaviour is maintained in eusocial species is a key topic in evolutionary biology. Colony-level sex investment ratio changes in response to relatedness asymmetries can dramatically influence inclusive fitness benefits for helpers in eusocial Hymenoptera. The extent to which helpers in primitively eusocial colonies can respond adaptively to different sources of variation in relatedness asymmetry is unclear. Using data from 109 colonies of the sweat bee Lasioglossum malachurum, we found that queen loss, but not multiple paternity or the presence of alien helpers, was correlated with colony sex investment ratios. Moreover, we quantified average helper-brood genetic relatedness to test whether it is higher than that predicted under solitary reproduction (r = 0.5). Values equal to and below r = 0.5 suggest that relatedness benefits alone cannot explain the maintenance of helping behaviour. Ecological benefits of group living and/or coercion must also contribute.
Abstract.
2020
Field J, Gonzalez-Voyer A, Boulton RA (2020). The evolution of parental care strategies in subsocial wasps.
Behavioral Ecology and Sociobiology,
74(6).
Abstract:
The evolution of parental care strategies in subsocial wasps
. Abstract
. Insect parental care strategies are particularly diverse, and prolonged association between parents and offspring may be a key precursor to the evolution of complex social traits. Macroevolutionary patterns remain obscure, however, due to the few rigorous phylogenetic analyses. The subsocial sphecid wasps are a useful group in which to study parental care because of the diverse range of strategies they exhibit. These strategies range from placing a single prey item in a pre-existing cavity to mass provisioning a pre-built nest, through to complex progressive provisioning where a female feeds larvae in different nests simultaneously as they grow. We show that this diversity stems from multiple independent transitions between states. The strategies we focus on were previously thought of in terms of a stepping-stone model in which complexity increases during evolution, ending with progressive provisioning which is a likely precursor to eusociality. We find that evolution has not always followed this model: reverse transitions are common, and the ancestral state is the most flexible rather than the simplest strategy. Progressive provisioning has evolved several times independently, but transitions away from it appear rare. We discuss the possibility that ancestral plasticity has played a role in the evolution of extended parental care.
.
. Significance statement
. Parental care behaviour leads to prolonged associations between parents and offspring, which is thought to drive the evolution of social living. Despite the importance of insect parental care for shaping the evolution of sociality, relatively few studies have attempted to reconstruct how different strategies evolve in the insects. In this study, we use phylogenetic methods to reconstruct the evolution of the diverse parental care strategies exhibited by the subsocial digger wasps (Sphecidae). Contrary to expectations, we show that parental care in this group has not increased in complexity over evolutionary time. We find that the ancestral state is not the simplest, but may be the most flexible strategy. We suggest that this flexible ancestral strategy may have allowed rapid response to changing environmental conditions which might explain the diversity in parental care strategies that we see in the digger wasps today.
.
Abstract.
2019
Field J (2019). Hover Wasps (Stenogastrinae). In (Ed) Encyclopedia of Social Insects, Springer Nature, 1-5.
Field JP, Couchoux C (2019). Parental manipulation of offspring size in social groups: a test using
paper wasps. Behavioral Ecology and Sociobiology
Field JP, Parsons P, Grinsted L (2019). Partner choice correlates with fine scale kin structuring in the paper wasp Polistes dominula. PLoS ONE
Field J, Toyoizumi H (2019). The evolution of eusociality: no risk‐return tradeoff but the ecology matters.
Ecology Letters,
23(3), 518-526.
Abstract:
The evolution of eusociality: no risk‐return tradeoff but the ecology matters
AbstractThe origin of eusociality in the Hymenoptera is a question of major interest. Theory has tended to focus on genetic relatedness, but ecology can be just as important a determinant of whether eusociality evolves. Using the model of Fu et al. (2015), we show how ecological assumptions critically affect the conclusions drawn. Fu et al. inferred that eusociality rarely evolves because it faces a fundamental ‘risk‐return tradeoff’. The intuitive logic was that worker production represents an opportunity cost because it delays realising a reproductive payoff. However, making empirically justified assumptions that (1) workers take over egg‐laying following queen death and (2) productivity increases gradually with each additional worker, we find that the risk‐return tradeoff disappears. We then survey Hymenoptera with more specialised morphological castes, and show how the interaction between two common features of eusociality – saturating birth rates and group size‐dependent helping decisions – can determine whether eusociality outperforms other strategies.
Abstract.
2018
Field JP, Pennell TM, Holman L, Morrow EH (2018). Building a new research framework for social evolution: intralocus caste antagonism. Biological Reviews
Field JP, Accleton C, Foster W (2018). Crozier’s effect and the acceptance of intraspecific brood parasites. Current Biology, 28, 3267-3272.
Davison PJ, Field J (2018). Environmental barriers to sociality in an obligate eusocial sweat bee. Insectes Sociaux, 65(4), 549-559.
Field JP, Davison P (2018). Limited social plasticity in the socially polymorphic sweat bee Lasioglossum calceatum. Behavioral Ecology and Sociobiology, 72, 56-56.
Field JP, Grinsted L (2018). Predictors of nest growth: diminishing returns for subordinates in the paper wasp Polistes dominula. Behavioral Ecology and Sociobiology, 72, 88-88.
2017
Grinsted L, Field J (2017). Biological markets in cooperative breeders: quantifying outside options.
Proceedings of the Royal Society B: Biological Sciences,
284(1856), 20170904-20170904.
Abstract:
Biological markets in cooperative breeders: quantifying outside options
. A major aim in evolutionary biology is to understand altruistic help and reproductive partitioning in cooperative societies, where subordinate helpers forego reproduction to rear dominant breeders' offspring. Traditional models of cooperation in these societies typically make a key assumption: that the only alternative to staying and helping is solitary breeding, an often unfeasible task. Using large-scale field experiments on paper wasps (
. Polistes dominula
. ), we show that individuals have high-quality alternative nesting options available that offer fitness payoffs just as high as their actual chosen options, far exceeding payoffs from solitary breeding. Furthermore, joiners could not easily be replaced if they were removed experimentally, suggesting that it may be costly for dominants to reject them. Our results have implications for expected payoff distributions for cooperating individuals, and suggest that biological market theory, which incorporates partner choice and competition for partners, is necessary to understand helping behaviour in societies like that of
. P. dominula
. Traditional models are likely to overestimate the incentive to stay and help, and therefore the amount of help provided, and may underestimate the size of reproductive concession required to retain subordinates. These findings are relevant for a wide range of cooperative breeders where there is dispersal between social groups.
.
Abstract.
Parsons PJ, Couchoux C, Horsburgh GJ, Dawson DA, Field J (2017). Identification of 24 new microsatellite loci in the sweat bee Lasioglossum malachurum (Hymenoptera: Halictidae).
BMC Res Notes,
10(1).
Abstract:
Identification of 24 new microsatellite loci in the sweat bee Lasioglossum malachurum (Hymenoptera: Halictidae).
OBJECTIVE: the objective here is to identify highly polymorphic microsatellite loci for the Palaearctic sweat bee Lasioglossum malachurum. Sweat bees (Hymenoptera: Halictidae) are widespread pollinators that exhibit an unusually large range of social behaviours from non-social, where each female nests alone, to eusocial, where a single queen reproduces while the other members of the colony help to rear her offspring. They thus represent excellent models for understanding social evolution. RESULTS: 24 new microsatellite loci were successfully optimized. When amplified across 23-40 unrelated females, the number of alleles per locus ranged from 3 to 17 and the observed heterozygosities 0.45 to 0.95. Only one locus showed evidence of significant deviation from Hardy-Weinberg equilibrium. No evidence of linkage disequilibrium was found. These 24 loci will enable researchers to gain greater understanding of colony relationships within this species, an important model for the study of eusociality. Furthermore, 22 of the same loci were also successfully amplified in L. calceatum, suggesting that these loci may be useful for investigating the ecology and evolution of sweat bees in general.
Abstract.
Author URL.
Grinsted L, Field J (2017). Market forces influence helping behaviour in cooperatively breeding paper wasps. Nature Communications, 8
DAVISON PJ, FIELD J (2017). Season length, body size, and social polymorphism: size clines but not saw tooth clines in sweat bees.
Ecological Entomology,
42(6), 768-776.
Abstract:
Season length, body size, and social polymorphism: size clines but not saw tooth clines in sweat bees
1. Annual insects are predicted to grow larger where the growing season is longer. However, transitions from one to two generations per year can occur when the season becomes sufficiently long, and are predicted to result in a sharp decrease in body size because available development time is halved. The potential for resulting saw‐tooth clines has been investigated only in solitary taxa with free‐living larvae.2. Size clines were investigated in two socially polymorphic sweat bees (Halictidae): transitions between solitary and social nesting occur along gradients of increasing season length, characterised by the absence or presence of workers and offspring that are individually mass provisioned by adults. How the body size changes with season length was examined, and whether transitions in social phenotype generate saw‐tooth size clines. We measured Lasioglossum calceatum and Halictus rubicundus nest foundresses originating from more than 1000 km of latitude, encompassing the transition between social and solitary nesting.3. Using satellite‐collected temperature data to estimate season length, it was shown that both species were largest where the season was longest. Body size increased linearly with season length in L. calceatum and non‐linearly in H. rubicundus but the existence of saw‐tooth clines was not supported.4. The present results suggest that because the amount of food consumed by offspring during development is determined by adults, environmental and social influences on the provisioning strategies of adult bees may be more important factors than available feeding time in determining offspring body size in socially polymorphic sweat bees.
Abstract.
2016
Schürch R, Accleton C, Field J (2016). Consequences of a warming climate for social organisation in sweat bees. Behavioral Ecology and Sociobiology, 70(8), 1131-1139.
Field J, Leadbeater E (2016). Cooperation between non-relatives in a primitively eusocial paper wasp. <i>Polistes dominula</i>.
Philosophical Transactions of the Royal Society B: Biological Sciences,
371(1687), 20150093-20150093.
Abstract:
Cooperation between non-relatives in a primitively eusocial paper wasp. Polistes dominula
. In cooperatively breeding vertebrates, the existence of individuals that help to raise the offspring of non-relatives is well established, but unrelated helpers are less well known in the social insects. Eusocial insect groups overwhelmingly consist of close relatives, so populations where unrelated helpers are common are intriguing. Here, we focus on
. Polistes dominula—
. the best-studied primitively eusocial wasp, and a species in which nesting with non-relatives is not only present but frequent. We address two major questions: why individuals should choose to nest with non-relatives, and why such individuals participate in the costly rearing of unrelated offspring.
. Polistes dominula
. foundresses produce more offspring of their own as subordinates than when they nest independently, providing a potential explanation for co-founding by non-relatives. There is some evidence that unrelated subordinates tailor their behaviour towards direct fitness, while the role of recognition errors in generating unrelated co-foundresses is less clear. Remarkably, the remote but potentially highly rewarding chance of inheriting the dominant position appears to strongly influence behaviour, suggesting that primitively eusocial insects may have much more in common with their social vertebrate counterparts than has commonly been thought.
.
Abstract.
Green JP, Almond EJ, Williamson J, Field J (2016). Regulation of host colony activity by the social parasite Polistes semenowi. Insectes Sociaux, 63(3), 385-393.
Davison PJ, Field J (2016). Social polymorphism in the sweat bee Lasioglossum (Evylaeus) calceatum. Insectes Sociaux, 63(2), 327-338.
2015
Field J, Shreeves G, Kennedy M, Brace S, Gilbert JDJ (2015). Sex-biased parental care and sexual size dimorphism in a provisioning arthropod. Behavioral Ecology and Sociobiology, 69(12), 1897-1906.
2014
Donaldson L, Thompson FJ, Field J, Cant MA (2014). Do paper wasps negotiate over helping effort?.
Behavioral Ecology,
25(1), 88-94.
Abstract:
Do paper wasps negotiate over helping effort?
Recent theory and empirical studies of avian biparental systems suggest that animals resolve conflict over parental care via a process of behavioral negotiation or "rules for responding." Less is known, however, about whether negotiation over helping effort occurs in cooperatively breeding animal societies or whether behavioral negotiation requires a relatively large brain. In this study, we tested whether negotiation over help occurs in a social insect, the paper wasp Polistes dominulus, by recording individual responses to both observed and experimentally induced foraging returns by other group members. In our experiments, we manipulated food delivery to the nest in 2 ways: 1) by catching departing foragers and giving them larval food to take back to the nest and 2) by giving larval food directly to wasps on the nest, which they then fed to larvae, so increasing food delivery independently of helper effort. We found no evidence from Experiment 1 that helpers adjusted their own foraging effort according to the foraging effort of other group members. However, when food was provided directly to the nest, wasps did respond by reducing their own foraging effort. One interpretation of this result is that paper wasp helpers adjust their helping effort according to the level of offspring need rather than the work rate of other helpers. Negotiation based on indicators of demand rather than work rate is a likely mechanism to resolve conflict over investment in teams where helpers cannot observe each other's work rate directly, as is commonly the case in insect and vertebrate societies. © the Author 2013.
Abstract.
Thompson FJ, Donaldson L, Johnstone RA, Field J, Cant MA (2014). Dominant aggression as a deterrent signal in paper wasps. Behavioral Ecology, 25(4), 706-715.
Toyoizumi H, Field J (2014). Dynamics of social queues. Journal of Theoretical Biology, 346, 16-22.
Toyoizumi H, Field J (2014). Reduction of Foraging Work and Cooperative Breeding. Acta Biotheoretica, 62(2), 123-132.
Green JP, Cant MA, Field J (2014). Using social parasitism to test reproductive skew models in a primitively eusocial wasp.
Proceedings. Biological sciences,
281(1789).
Abstract:
Using social parasitism to test reproductive skew models in a primitively eusocial wasp.
Remarkable variation exists in the distribution of reproduction (skew) among members of cooperatively breeding groups, both within and between species. Reproductive skew theory has provided an important framework for understanding this variation. In the primitively eusocial Hymenoptera, two models have been routinely tested: concessions models, which assume complete control of reproduction by a dominant individual, and tug-of-war models, which assume on-going competition among group members over reproduction. Current data provide little support for either model, but uncertainty about the ability of individuals to detect genetic relatedness and difficulties in identifying traits conferring competitive ability mean that the relative importance of concessions versus tug-of-war remains unresolved. Here, we suggest that the use of social parasitism to generate meaningful variation in key social variables represents a valuable opportunity to explore the mechanisms underpinning reproductive skew within the social Hymenoptera. We present a direct test of concessions and tug-of-war models in the paper wasp Polistes dominulus by exploiting pronounced changes in relatedness and power structures that occur following replacement of the dominant by a congeneric social parasite. Comparisons of skew in parasitized and unparasitized colonies are consistent with a tug-of-war over reproduction within P. dominulus groups, but provide no evidence for reproductive concessions.
Abstract.
2013
Leadbeater E, Dapporto L, Turillazzi S, Field J (2013). Available kin recognition cues may explain why wasp behavior reflects relatedness to nest mates. Behavioral Ecology, 25(2), 344-351.
Lucas ER, Field J (2013). Caste determination through mating in primitively eusocial societies. Journal of Theoretical Biology, 335, 31-39.
Green JP, Leadbeater E, Carruthers JM, Rosser NS, Lucas ER, Field J (2013). Clypeal patterning in the paper wasp Polistes dominulus: no evidence of adaptive value in the wild. Behavioral Ecology, 24(3), 623-633.
2012
Toyoizumi H, Field J (2012). Analysis of the dynamics of social queues by quasi-birth-and-death processes (abstract only). ACM SIGMETRICS Performance Evaluation Review, 39(4), 29-30.
Field J, Paxton R, Soro A, Craze P, Bridge C (2012). Body size, demography and foraging in a socially plastic sweat bee: a common garden experiment. Behavioral Ecology and Sociobiology, 66(5), 743-756.
Lengronne T, Leadbeater E, Patalano S, Dreier S, Field J, Sumner S, Keller L (2012). Little effect of seasonal constraints on population genetic structure in eusocial paper wasps. Ecology and Evolution, 2(10), 2615-2624.
Johnstone RA, Cant MA, Field J (2012). Sex-biased dispersal, haplodiploidy and the evolution of helping in social insects.
Proc Biol Sci,
279(1729), 787-793.
Abstract:
Sex-biased dispersal, haplodiploidy and the evolution of helping in social insects.
In his famous haplodiploidy hypothesis, W. D. Hamilton proposed that high sister-sister relatedness facilitates the evolution of kin-selected reproductive altruism among Hymenopteran females. Subsequent analyses, however, suggested that haplodiploidy cannot promote altruism unless altruists capitalize on relatedness asymmetries by helping to raise offspring whose sex ratio is more female-biased than the population at large. Here, we show that haplodiploidy is in fact more favourable than is diploidy to the evolution of reproductive altruism on the part of females, provided only that dispersal is male-biased (no sex-ratio bias or active kin discrimination is required). The effect is strong, and applies to the evolution both of sterile female helpers and of helping among breeding females. Moreover, a review of existing data suggests that female philopatry and non-local mating are widespread among nest-building Hymenoptera. We thus conclude that Hamilton was correct in his claim that 'family relationships in the Hymenoptera are potentially very favourable to the evolution of reproductive altruism'.
Abstract.
Author URL.
Green JP, Rose C, Field J (2012). The Role of Climatic Factors in the Expression of an Intrasexual Signal in the Paper Wasp <i><scp>P</scp>olistes dominulus</i>.
Ethology,
118(8), 766-774.
Abstract:
The Role of Climatic Factors in the Expression of an Intrasexual Signal in the Paper Wasp Polistes dominulus
AbstractWithin a species, variation in the use of sexual signals is observed between different populations. For intersexual traits, differences in the environmental conditions experienced by populations can play an important role in driving variation in male ornaments and female preferences. However, little is known about the factors maintaining variation in intrasexual traits used in competition. In this study, we investigate the role of climatic conditions in maintaining variation in the expression of an intrasexual signal in the paper wasp Polistes dominulus. The results of an experiment in which pupae were housed under different temperature and humidity conditions revealed a strong effect of temperature during pupal development on the expression of the signal. Furthermore, a comparison of survival and body weight between wasps reared at different temperatures indicates that signal expression exhibits phenotypic plasticity in response to developmental temperature. The effect of temperature on signal expression is consistent with patterns of signal expression observed across populations in the wild and suggests that climatic conditions may act to constrain signal expression in some populations but not in others, driving variation in signal use within P. dominulus. Environmental conditions may therefore be important in defining the scope for intrasexual signalling in animal populations and, in doing so, may play a role in maintaining variation in intrasexual traits in the face of sexual selection.
Abstract.
2011
FIELD J, OHL M, KENNEDY M (2011). A molecular phylogeny for digger wasps in the tribe Ammophilini (Hymenoptera, Apoidea, Sphecidae). Systematic Entomology, 36(4), 732-740.
Lucas ER, Field J (2011). Active and effective nest defence by males in a social apoid wasp. Behavioral Ecology and Sociobiology, 65(8), 1499-1504.
Green JP, Field J (2011). Assessment between species: information gathering in usurpation contests between a paper wasp and its social parasite. Animal Behaviour, 81(6), 1263-1269.
Lucas ER, Field J (2011). Assured fitness returns in a social wasp with no worker caste.
Proceedings of the Royal Society B: Biological Sciences,
278(1720), 2991-2995.
Abstract:
Assured fitness returns in a social wasp with no worker caste
. The theory of assured fitness returns proposes that individuals nesting in groups gain fitness benefits from effort expended in brood-rearing, even if they die before the young that they have raised reach independence. These benefits, however, require that surviving nest-mates take up the task of rearing these young. It has been suggested that assured fitness returns could have favoured group nesting even at the origin of sociality (that is, in species without a dedicated worker caste). We show that experimentally orphaned brood of the apoid wasp
. Microstigmus nigrophthalmus
. continue to be provisioned by surviving adults for at least two weeks after the orphaning. This was the case for brood of both sexes. There was no evidence that naturally orphaned offspring received less food than those that still had mothers in the nest. Assured fitness returns can therefore represent a real benefit to nesting in groups, even in species without a dedicated worker caste.
.
Abstract.
Zanette LRS, Field J (2011). Founders versus joiners: group formation in the paper wasp Polistes dominulus. Animal Behaviour, 82(4), 699-705.
Abbot P, Abe J, Alcock J, Alizon S, Alpedrinha JAC, Andersson M, Andre J-B, van Baalen M, Balloux F, Balshine S, et al (2011). Inclusive fitness theory and eusociality.
Nature,
471(7339), E1-E4.
Abstract:
Inclusive fitness theory and eusociality.
Arising from M. A. Nowak, C. E. Tarnita & E. O. Wilson 466, 1057-1062 (2010); Nowak et al. reply. Nowak et al. argue that inclusive fitness theory has been of little value in explaining the natural world, and that it has led to negligible progress in explaining the evolution of eusociality. However, we believe that their arguments are based upon a misunderstanding of evolutionary theory and a misrepresentation of the empirical literature. We will focus our comments on three general issues.
Abstract.
Author URL.
Green JP, Field J (2011). Interpopulation variation in status signalling in the paper wasp Polistes dominulus. Animal Behaviour, 81(1), 205-209.
Leadbeater E, Carruthers JM, Green JP, Rosser NS, Field J (2011). Nest Inheritance is the Missing Source of Direct Fitness in a Primitively Eusocial Insect.
Science,
333(6044), 874-876.
Abstract:
Nest Inheritance is the Missing Source of Direct Fitness in a Primitively Eusocial Insect
. Fitness benefits from the inheritance of breeding resources may explain why
. Polistes
. wasps cooperate with nonrelatives.
.
Abstract.
Lucas ER, Martins RP, Field J (2011). Reproductive skew is highly variable and correlated with genetic relatedness in a social apoid wasp. Behavioral Ecology, 22(2), 337-344.
2010
Cronin AL, Bridge C, Field J (2010). Climatic correlates of temporal demographic variation in the tropical hover wasp Liostenogaster flavolineata. Insectes Sociaux, 58(1), 23-29.
Field J, Paxton RJ, Soro A, Bridge C (2010). Cryptic Plasticity Underlies a Major Evolutionary Transition. Current Biology, 20(22), 2028-2031.
SORO A, FIELD J, BRIDGE C, CARDINAL SC, PAXTON RJ (2010). Genetic differentiation across the social transition in a socially polymorphic sweat bee, Halictus rubicundus. Molecular Ecology, 19(16), 3351-3363.
Lucas ER, Martins RP, Zanette LRS, Field J (2010). Social and genetic structure in colonies of the social wasp Microstigmus nigrophthalmus. Insectes Sociaux, 58(1), 107-114.
Leadbeater E, Carruthers JM, Green JP, van Heusden J, Field J (2010). Unrelated Helpers in a Primitively Eusocial Wasp: is Helping Tailored Towards Direct Fitness?. PLoS ONE, 5(8), e11997-e11997.
2009
LUCAS ER, HORSBURGH GJ, DAWSON DA, FIELD J (2009). Characterization of microsatellite loci isolated from the wasp, <i>Microstigmus nigrophthalmus</i> (Hymenoptera).
Molecular Ecology Resources,
9(6), 1492-1497.
Abstract:
Characterization of microsatellite loci isolated from the wasp, Microstigmus nigrophthalmus (Hymenoptera)
AbstractFifty‐two microsatellite loci were characterized in 22–31 unrelated females of the wasp (Microstigmus nigrophthalmus) collected from the Mata do Paraiso, Viçosa, M.G. Brazil. Fifty‐one of these loci were developed from a microsatellite‐enriched genomic library derived from M. nigrophthalmus and one was derived from the wasp, Ormyrus nitidulus. The genus Microstigmus represents an independent origin of social behaviour in the Hymenoptera and is thus of great potential in the study of social evolution.
Abstract.
Zanette L, Field J (2009). Cues, concessions, and inheritance: dominance hierarchies in the paper wasp Polistes dominulus. Behavioral Ecology, 20(4), 773-780.
Field J, Cant, M.A. (2009). Reproductive skew in primitively eusocial insects: lessons for vertebrates. In Hager R, Jones CB (Eds.)
Reproductive Skew in Vertebrates, Cambridge: Cambridge University Press, 305-334.
Abstract:
Reproductive skew in primitively eusocial insects: lessons for vertebrates.
Abstract.
Field J, Cant MA (2009). Social stability and helping in small animal societies.
Philos Trans R Soc Lond B Biol Sci,
364(1533), 3181-3189.
Abstract:
Social stability and helping in small animal societies.
In primitively eusocial societies, all individuals can potentially reproduce independently. The key fact that we focus on in this paper is that individuals in such societies instead often queue to inherit breeding positions. Queuing leads to systematic differences in expected future fitness. We first discuss the implications this has for variation in behaviour. For example, because helpers nearer to the front of the queue have more to lose, they should work less hard to rear the dominant's offspring. However, higher rankers may be more aggressive than low rankers, even if they risk injury in the process, if aggression functions to maintain or enhance queue position. Second, we discuss how queuing rules may be enforced through hidden threats that rarely have to be carried out. In fishes, rule breakers face the threat of eviction from the group. In contrast, subordinate paper wasps are not injured or evicted during escalated challenges against the dominant, perhaps because they are more valuable to the dominant. We discuss evidence that paper-wasp dominants avoid escalated conflicts by ceding reproduction to subordinates. Queuing rules appear usually to be enforced by individuals adjacent in the queue rather than by dominants. Further manipulative studies are required to reveal mechanisms underlying queue stability and to elucidate what determines queue position in the first place.
Abstract.
Author URL.
2008
Paxton RJ, Ayasse M, Field J, Soro A (2008). Complex sociogenetic organization and reproductive skew in a primitively eusocial sweat bee, Lasioglossum malachurum, as revealed by microsatellites. Molecular Ecology, 11(11), 2405-2416.
Zanette LRS, Field J (2008). Genetic relatedness in early associations of Polistes dominulus : from related to unrelated helpers. Molecular Ecology, 17(11), 2590-2597.
2007
Field J, Cant MA (2007). Direct fitness, reciprocity and helping: a perspective from primitively eusocial wasps.
Behav Processes,
76(2), 160-162.
Author URL.
Shreeves G, Field J (2007). Parental care and sexual size dimorphism in wasps and bees. Behavioral Ecology and Sociobiology, 62(5), 843-852.
Bridge C, Field J (2007). Queuing for dominance: gerontocracy and queue-jumping in the hover wasp Liostenogaster flavolineata. Behavioral Ecology and Sociobiology, 61(8), 1253-1259.
Cronin A, Field J (2007). Social aggression in an age-dependent dominance hierarchy. Behaviour, 144(7), 753-765.
2006
Bolton A, Sumner S, Shreeves G, Casiraghi M, Field J (2006). Colony genetic structure in a facultatively eusocial hover wasp. Behavioral Ecology, 17(6), 873-880.
Field J, Turner E, Fayle T, Foster WA (2006). Costs of egg-laying and offspring provisioning: multifaceted parental investment in a digger wasp.
Proceedings of the Royal Society B: Biological Sciences,
274(1608), 445-451.
Abstract:
Costs of egg-laying and offspring provisioning: multifaceted parental investment in a digger wasp
. Nest-building Hymenoptera have been a major testing ground for theories of parental investment and sex allocation. Investment has usually been estimated by the likely costs of offspring provisioning, ignoring other aspects of parental care. Using three experimental treatments, we estimated the costs of egg-laying and provisioning separately under field conditions in a digger wasp
. Ammophila pubescens
. In one treatment, we increased the provisioning effort required per offspring by removing alternate prey items as they were brought to the nest. In two other treatments, we reduced parental effort by either preventing females from provisioning alternate nests or preventing them from both ovipositing and provisioning. Our results indicate that both egg-laying and provisioning represent significant costs of reproduction, expressed as differences in productivity but not survival. A trade-off-based model suggests that other components of parental care such as nest initiation may also represent significant costs. Costs of egg production and nest initiation are probably similar for male and female offspring, so that taking them into account leads to a less male-biased expected sex ratio. Mothers compensated only partially for prey removal in terms of the total provisions they gave to individual offspring.
.
Abstract.
Cant MA, English S, Reeve HK, Field J (2006). Escalated conflict in a social hierarchy.
Proc Biol Sci,
273(1604), 2977-2984.
Abstract:
Escalated conflict in a social hierarchy.
Animals that live in cooperative societies form hierarchies in which dominant individuals reap disproportionate benefits from group cooperation. The stability of these societies requires subordinates to accept their inferior status rather than engage in escalated conflict with dominants over rank. Applying the logic of animal contests to these cases predicts that escalated conflict is more likely where subordinates are reproductively suppressed, where group productivity is high, relatedness is low, and where subordinates are relatively strong. We tested these four predictions in the field on co-foundress associations of the paper wasp Polistes dominulus by inducing contests over dominance rank experimentally. Subordinates with lower levels of ovarian development, and those in larger, more productive groups, were more likely to escalate in conflict with their dominant, as predicted. Neither genetic relatedness nor relative body size had significant effects on the probability of escalation. The original dominant emerged as the winner in all except one escalated contest. The results provide the first evidence that reproductive suppression of subordinates increases the threat of escalated conflict, and hence that reproductive sharing can promote stability of the dominant-subordinate relationship.
Abstract.
Author URL.
Field J, Cronin A, Bridge C (2006). Future fitness and helping in social queues. Nature, 441(7090), 214-217.
Cant MA, Llop JB, Field J (2006). Individual variation in social aggression and the probability of inheritance: theory and a field test.
The American naturalist,
167(6), 837-852.
Abstract:
Individual variation in social aggression and the probability of inheritance: theory and a field test.
Recent theory suggests that much of the wide variation in individual behavior that exists within cooperative animal societies can be explained by variation in the future direct component of fitness, or the probability of inheritance. Here we develop two models to explore the effect of variation in future fitness on social aggression. The models predict that rates of aggression will be highest toward the front of the queue to inherit and will be higher in larger, more productive groups. A third prediction is that, in seasonal animals, aggression will increase as the time available to inherit the breeding position runs out. We tested these predictions using a model social species, the paper wasp Polistes dominulus. We found that rates of both aggressive "displays" (aimed at individuals of lower rank) and aggressive "tests" (aimed at individuals of higher rank) decreased down the hierarchy, as predicted by our models. The only other significant factor affecting aggression rates was date, with more aggression observed later in the season, also as predicted. Variation in future fitness due to inheritance rank is the hidden factor accounting for much of the variation in aggressiveness among apparently equivalent individuals in this species.
Abstract.
Cronin AL, Field J (2006). Rank and colony defense against conspecifics in a facultatively eusocial hover wasp. Behavioral Ecology, 18(2), 331-336.
Mesterton-Gibbons M, Hardy ICW, Field J (2006). The effect of differential survivorship on the stability of reproductive queueing. Journal of Theoretical Biology, 242(3), 699-712.
2005
Field, J. (2005). Helping effort in a dominance hierarchy. Behavioral Ecology, 16, 708-715
Sumner S, Field J (2005). Highly polymorphic microsatellite loci in the facultatively eusocial hover wasp, Liostenogaster flavolineata and cross‐species amplification. Molecular Ecology Resources, 1(4), 229-231.
Field J (2005). The evolution of progressive provisioning. Behavioral Ecology, 16(4), 770-778.
2004
Field J, Brace S (2004). Pre-social benefits of extended parental care. Nature, 428(6983), 650-652.
2003
Shreeves G, Cant MA, Bolton A, Field J (2003). Insurance-based advantages for subordinate co-foundresses in a temperate paper wasp.
Proc Biol Sci,
270(1524), 1617-1622.
Abstract:
Insurance-based advantages for subordinate co-foundresses in a temperate paper wasp.
Recent explanations for the evolution of eusociality, focusing more on costs and benefits than relatedness, are largely untested. We validate one such model by showing that helpers in foundress groups of the paper wasp Polistes dominulus benefit from an insurance-based mechanism known as Assured Fitness Returns (AFRs). Experimental helper removals left remaining group members with more offspring than they would normally rear. Reduced groups succeeded in preserving the dead helpers' investment by rearing these extra offspring, even when helper removals occurred long before worker emergence. While helpers clearly gained from AFRs, offspring of lone foundresses failed after foundress death, so that AFRs represent a true advantage for helpers. Smaller, less valuable offspring were probably sacrificed to feed larger offspring, but reduced groups did not preferentially attract joiners or increase their foraging effort to compensate for their smaller workforce. We failed to detect a second insurance-based advantage, Survivorship Insurance, in which larger groups are less likely to fail than smaller groups. We suggest that through their use of small offspring as a food store to cope with temporary shortages, wasps may be less susceptible than vertebrates to offspring failure following the death of group members.
Abstract.
Author URL.
Paxton RJ, Arévalo E, Field J (2003). Microsatellite loci for the eusocial Lasioglossum malachurum and other sweat bees (Hymenoptera, Halictidae). Molecular Ecology Resources, 3(1), 82-84.
2002
Shreeves G, Field J (2002). Group Size and Direct Fitness in Social Queues. The American Naturalist, 159(1), 81-95.
Sumner S, Casiraghi M, Foster W, Field J (2002). High reproductive skew in tropical hover wasps. Proceedings of the Royal Society B, 269(1487), 179-186.
2001
Cant MA, Field J (2001). Helping effort and future fitness in cooperation animal societies.
Proc Biol Sci,
268(1479), 1959-1964.
Abstract:
Helping effort and future fitness in cooperation animal societies.
Little attention has been paid to a conspicuous and universal feature of animal societies: the variation between individuals in helping effort. Here, we develop a multiplayer kin-selection model that assumes that subordinates face a trade-off because current investment in help reduces their own future reproductive success. The model makes two predictions: (i) subordinates will work less hard the closer they are to inheriting breeding status; and (ii) for a given dominance rank, subordinates will work less hard in larger groups. The second prediction reflects the larger pay-off from inheriting a larger group. Both predictions were tested through a field experiment on the paper wasp Polistes dominulus. First, we measured an index of helping effort among subordinates, then we removed successive dominants to reveal the inheritance ranks of the subordinates: their positions in the queue to inherit dominance. We found that both inheritance rank and group size had significant effects on helping effort, in the manner predicted by our model. The close match between our theoretical and empirical results suggests that individuals adjust their helping effort according to their expected future reproductive success. This relationship has probably remained hidden in previous studies that have focused on variation in genetic relatedness.
Abstract.
Author URL.
2000
Field J, Shreeves G, Sumner S, Casiraghi M (2000). Insurance-based advantage to helpers in a tropical hover wasp. Nature, 404(6780), 869-871.
1999
Field J, Shreeves G, Sumner S (1999). Group size, queuing and helping decisions in facultatively eusocial hover wasps. Behavioral Ecology and Sociobiology, 45(5), 378-385.
FIELD J, FOSTER W (1999). Helping behaviour in facultatively eusocial hover wasps: an experimental test of the subfertility hypothesis. Animal Behaviour, 57(3), 633-636.
1998
Field J, Foster W, Shreeves G, Sumner S (1998). Ecological constraints on independent nesting in facultatively eusocial hover wasps. Proceedings of the Royal Society B, 265(1400), 973-977.
