Transcriptomes of parents identify parenting strategies and sexual conflict in a subsocial beetle

This work was funded by UK NERC grants to M.G.R. and A.J.M. an NERC studentship to D.J.P. the University of Georgia and a US NSF grant to A.J.M. and M.G.R.Parenting in the burying beetle Nicrophorus vespilloides is complex and, unusually, the sex and number of parents that can be present is flexible. Such flexibility is expected to involve specialized behaviour by the two sexes under biparental conditions. Here, we show that offspring fare equally well regardless of the sex or number of parents present. Comparing transcriptomes, we find a largely overlapping set of differentially expressed genes in both uniparental and biparental females and in uniparental males including vitellogenin, associated with reproduction, and takeout, influencing sex-specific mating and feeding behaviour. Gene expression in biparental males is similar to that in non-caring states. Thus, being ‘biparental’ in N. vespilloides describes the family social organization rather than the number of directly parenting individuals. There was no specialization; instead, in biparental families, direct male parental care appears to be limited with female behaviour unchanged. This should lead to strong sexual conflict.Publisher PDFPeer reviewe

The Genome and Methylome of a Beetle with Complex Social Behavior,Nicrophorus vespilloides(Coleoptera: Silphidae)

Testing for conserved and novelmechanisms underlying phenotypic evolution requires a diversity of genomes available for comparisonspanning multiple independent lineages. For example, complex social behavior in insects has been investigated primarily witheusocial lineages, nearly all of which are Hymenoptera. If conserved genomic influences on sociality do exist, we need data from awider range of taxa that also vary in their levels of sociality. Here,we present the assembled and annotated genome of the subsocialbeetle Nicrophorus vespilloides, a species long used to investigate evolutionary questions of complex social behavior. We used thisgenome to address two questions. First, do aspects of life history, such as using a carcass to breed, predict overlap in gene modelsmore strongly than phylogeny? We found that the overlap in gene models was similar between N. vespilloides and all other insectgroups regardless of life history. Second, like other insects with highly developed social behavior but unlike other beetles, doesN. vespilloides have DNA methylation?We found strong evidence for an active DNA methylation system. The distribution of methylationwassimilar to other insects with exons having themostmethylatedCpGs. Methylation status appears highly conserved; 85%of themethylated genes in N. vespilloides are alsomethylated in the hymentopteran Nasonia vitripennis. The addition of this genomeadds a coleopteran resource to answer questions about the evolution and mechanistic basis of sociality and to address questionsabout the potential role of methylation in social behavior

Ethological principles predict the neuropeptides co-opted to influence parenting

Ethologists predicted that parental care evolves by modifying behavioural precursors in the asocial ancestor. As a corollary, we predict that the evolved mechanistic changes reside in genetic pathways underlying these traits. Here we test our hypothesis in female burying beetles, Nicrophorus vespilloides, an insect where caring adults regurgitate food to begging, dependent offspring. We quantify neuropeptide abundance in brains collected from three behavioural states: solitary virgins, individuals actively parenting or post-parenting solitary adults and quantify 133 peptides belonging to 18 neuropeptides. Eight neuropeptides differ in abundance in one or more states, with increased abundance during parenting in seven. None of these eight neuropeptides have been associated with parental care previously, but all have roles in predicted behavioural precursors for parenting. Our study supports the hypothesis that predictable traits and pathways are targets of selection during the evolution of parenting and suggests additional candidate neuropeptides to study in the context of parenting

Data from: The effect of hydroperiod and predation on the diversity of temporary pond zooplankton communities

In temporary pond ecosystems, it is hypothesized that the two dominant structuring forces on zooplankton communities are predation and demographic constraints due to wetland drying. Both of these forces are deterministic processes that act most strongly at opposing ends of a hydroperiod gradient. Our objective was to test how these two processes affect α- and β-diversity of zooplankton communities derived from a diverse temporary pond system. We hypothesized that decreased hydroperiod length and the presence of salamander larvae as predators would decrease β-diversity and that intermediate hydroperiod communities would have the greatest species richness. Our 1-year mesocosm experiment (n = 36) consisted of two predation treatments (present/absent) and three hydroperiod treatments (short/medium/long) fully crossed, seeded from the resting egg bank of multiple temporary ponds. In total, we collected 37 species of microcrustacean zooplankton from our mesocosms. A reduction in hydroperiod length resulted in lower α-diversity, with short-hydroperiod treatments affected most strongly. Endpoint community dissimilarity (β-diversity) was greatest in the medium-hydroperiod treatment with regard to species presence/absence, but was greatest in the long-hydroperiod treatment when abundances were included. Predation by salamander larvae led to reduced β-diversity with respect to species presence/absence, but not among abundant species, and had no effect on α-diversity. Our results suggest that environmental changes that reduce hydroperiod length would result in reduced α-diversity; however, intermediate hydroperiod length appear to enhance β-diversity within a group of wetlands

Zokan 2015 Savannah River Site Zooplankton Data

The data associated with Marcus Zokan's dissertation (2015) on zooplankton communities of ephemeral wetlands (Carolina Bays) at the Savannah River Site

Data from: Zooplankton species diversity in the temporary wetland system of the Savannah River Site, South Carolina, USA

Understanding how diverse species communities develop and how the species within them coexist is one of the central questions in community ecology. The temporary wetland system occurring on the Savannah River Site near Aiken, South Carolina is home to the most species rich temporary wetland zooplankton assemblage known in the world. While previous research has documented this remarkable diversity, there has been little study directed at understanding how diversity is distributed at the landscape and local scales or on investigating potential mechanisms of what has led to the high richness of this system. The collection of studies presented here examine diversity patterns in the zooplankton community, links these patterns to spatial and temporal variation, experimentally tests the effects of two important environmental factors on diversity, and describes two new species. Results indicate that long hydroperiod lengths were associated with high species richness. Wetlands with similar species assemblages were generally closer together, suggesting the importance of dispersal. Over the course of a year, diversity increased during the spring and summer months and declined toward the fall, these changes were associated with low pH, low conductivity, and high water temperature. Vegetated areas within wetlands had greater diversity than did unvegetated areas, and diversity was particularly low in areas of decaying vegetation. Temporal comparisons provide evidence for distinct seasonal communities that arise every year. Experimental tests of the impact of hydroperiod length on diversity found that shorter hydroperiods resulted in reduced species richness, and communities dominated by just a few species. Predation was found to have no effect on diversity or community composition. During investigation of the diversity of these wetlands, two new species of the genus Chydorus were discovered and described. These two species differ from congeners both in morphology and phylogenetically. Together these studies describe how environmental variation can impact the diversity of the zooplankton communities within temporary wetlands and show how hydroperiod limits the richness of these systems. The results presented here provide insight into the forces that may lead to diverse communities in temporary wetlands, providing direction for future research into these dynamic ecosystems

Mesocosm_water_conditions

contains water condition data from each mesocosm collected at every sampling dat

Mesocosm_treatments

identifies the experimental treatments imposed on each mesocos

Mesocosm_sample_data

contains the abundance and identity of each taxon collecte