Health and Survival of Moon Jellies (Aurelia Aurita) in Hand-Built Pseudo-Kreisel Aquaria

Jellies are typically considered difficult organisms to raise in the lab by many scientists. This is due to their requirements for constant water current and the absence of corners. In the wild, jellies such as moon jellies (Aurelia aurita) rarely encounter habitats outside of the open ocean where they are part of the plankton, so they are not adapted to navigate obstacles or get out of small spaces such as the corners of aquaria. In order to conduct an experiment utilizing live moon jellies to assess their utility in bioremediation of oil spills, we designed and built 4 pseudo-kreisel aquaria to house our jellies using a limited budget and many readily-available materials. Here, we present the methods used to construct these aquaria inexpensively (important for undergraduate research!) and evidence of their effectiveness in long-term housing of live jellies so that other researchers interested in jelly research can construct similar housing. Briefly, we removed the corners from 10 gallon aquaria and also provided for continuous circular water currents by adding quarter pieces of the sides of 5 gallon buckets attached via silicon sealant. Current was provided by spray bars that provided even water flow in all areas of the aquaria, driven by pumps in the external sump and filtration systems. We built the sump/filtration systems using 5-gallon buckets containing bio-balls and filter floss. Water was delivered to the sumps via PVC overflow plumbed into the aquaria via a bulkhead set into the glass at the desired water level. The overflows were covered with a small piece of fine screen and directly behind the spray bars in order to prevent jellies from becoming stuck as water leaves the system for filtration. Results of husbandry including survival and indicators of jelly health such as pulsing rate and holes in their bells over approximately 3 months will be presented

History of the introduction of a species resembling the benthic foraminifera Nonionella stella in the Oslofjord (Norway): morphological, molecular and paleo-ecological evidences

Specimens resembling the benthic foraminifera Nonionella stella (Cushman and Moyer, 1930), a morphospecies originally described from the San Pedro Basin, California, USA, were observed for the first time in the Oslofjord (Norway) in 2012. This study investigates the Oslofjord Nonionella population in order to confirm its non-indigenous species (NIS) status and assess its introduction time. Morphological characterisation based on SEM imaging complemented by molecular identification using small subunit (SSU) rDNA sequencing and assessment of the recent past record (sediment core), were performed on material collected in the Oslofjord in 2016. Examination of the dead fauna showed that specimens resembling N. stella only appeared recently in the Oslofjord, confirming the NIS status of this population. Moreover, DNA results indicate that the Oslofjord specimens differ genetically from N. stella sampled in the Santa Barbara Basin (California USA). Hence, we propose to use the name Nonionella sp. T1 for the specimens sampled in the Oslofjord for the time being. In the southern part of the Skagerrak, specimens morphologically similar to Nonionella sp. T1 were reported as NIS in the Gullmar fjord (Sweden) in 2011 and in the Skagerrak in 2015. Molecular data indicate that the two populations from Gullmar- and Oslofjords are identical, based on their SSU rDNA sequences. In addition, analyses of foraminiferal dead assemblages suggest that the population from the Gullmar fjord settled prior to the Oslofjord population, i.e. ~ 1985 and about 2010, respectively. This implies that Nonionella sp. T1 may have been transported from Sweden to Norway by northward coastal currents.Publisher PDFPeer reviewe

Side-Payments and the Costs of Conflict

Conflict and competition often impose costs on both winners and losers, and conflicting parties may prefer to resolve the dispute before it occurs. The equilibrium of a conflict game with side-payments predicts that with binding offers, proposers make and responders accept side-payments, generating settlements that strongly favor proposers. When side-payments are non-binding, proposers offer nothing and conflicts always arise. Laboratory experiments confirm that binding side-payments reduce conflicts. However, 30 % of responders reject binding offers, and offers are more egalitarian than predicted. Surprisingly, non-binding side-payments also improve efficiency, although less than binding. With binding side-payments, 87 % of efficiency gains come from avoided conflicts. However, with non-binding side-payments, only 39 % of gains come from avoided conflicts and 61 % from reduced conflict expenditures

A Low Concentration of Ethanol Impairs Learning but Not Motor and Sensory Behavior in Drosophila Larvae

Drosophila melanogaster has proven to be a useful model system for the genetic analysis of ethanol-associated behaviors. However, past studies have focused on the response of the adult fly to large, and often sedating, doses of ethanol. The pharmacological effects of low and moderate quantities of ethanol have remained understudied. In this study, we tested the acute effects of low doses of ethanol (∼7 mM internal concentration) on Drosophila larvae. While ethanol did not affect locomotion or the response to an odorant, we observed that ethanol impaired associative olfactory learning when the heat shock unconditioned stimulus (US) intensity was low but not when the heat shock US intensity was high. We determined that the reduction in learning at low US intensity was not a result of ethanol anesthesia since ethanol-treated larvae responded to the heat shock in the same manner as untreated animals. Instead, low doses of ethanol likely impair the neuronal plasticity that underlies olfactory associative learning. This impairment in learning was reversible indicating that exposure to low doses of ethanol does not leave any long lasting behavioral or physiological effects

A new integrated approach to taxonomy: the fusion of molecular and morphological systematics with type material in benthic foraminifera (dataset)

Topotypic specimens: accession numbers KX228717 - KX22873

A new integrated approach to taxonomy: the fusion of molecular and morphological systematics with type material in benthic foraminifera (dataset)

Topotypic specimens: accession numbers KX228717 - KX22873

Resistance to <i>Rhynchosporium commune</i> in a collection of European spring barley germplasm

Key messageAssociation analyses of resistance to Rhynchosporium commune in a collection of European spring barley germplasm detected 17 significant resistance quantitative trait loci. The most significant association was confirmed as Rrs1.AbstractRhynchosporium commune is a fungal pathogen of barley which causes a highly destructive and economically important disease known as rhynchosporium. Genome-wide association mapping was used to investigate the genetic control of host resistance to R. commune in a collection of predominantly European spring barley accessions. Multi-year disease nursery field trials revealed 8 significant resistance quantitative trait loci (QTL), whilst a separate association mapping analysis using historical data from UK national and recommended list trials identified 9 significant associations. The most significant association identified in both current and historical data sources, collocated with the known position of the major resistance gene Rrs1. Seedling assays with R. commune single-spore isolates expressing the corresponding avirulence protein NIP1 confirmed that this locus is Rrs1. These results highlight the significant and continuing contribution of Rrs1 to host resistance in current elite spring barley germplasm. Varietal height was shown to be negatively correlated with disease severity, and a resistance QTL was identified that co-localised with the semi-dwarfing gene sdw1, previously shown to contribute to disease escape. The remaining QTL represent novel resistances that are present within European spring barley accessions. Associated markers to Rrs1 and other resistance loci, identified in this study, represent a set of tools that can be exploited by breeders for the sustainable deployment of varietal resistance in new cultivars

Resistance to Rhynchosporium commune in a collection of European spring barley germplasm

Key message Association analyses of resistance to Rhynchosporium commune in a collection of European spring barley germplasm detected 17 significant resistance quantitative trait loci. The most significant association was confirmed as Rrs1. Abstract Rhynchosporium commune is a fungal pathogen of barley which causes a highly destructive and economically important disease known as rhynchosporium. Genome-wide association mapping was used to investigate the genetic control of host resistance to R. commune in a collection of predominantly European spring barley accessions. Multi-year disease nursery field trials revealed 8 significant resistance quantitative trait loci (QTL), whilst a separate association mapping analysis using historical data from UK national and recommended list trials identified 9 significant associations. The most significant association identified in both current and historical data sources, collocated with the known position of the major resistance gene Rrs1. Seedling assays with R. commune single-spore isolates expressing the corresponding avirulence protein NIP1 confirmed that this locus is Rrs1. These results highlight the significant and continuing contribution of Rrs1 to host resistance in current elite spring barley germplasm. Varietal height was shown to be negatively correlated with disease severity, and a resistance QTL was identified that co-localised with the semi-dwarfing gene sdw1, previously shown to contribute to disease escape. The remaining QTL represent novel resistances that are present within European spring barley accessions. Associated markers to Rrs1 and other resistance loci, identified in this study, represent a set of tools that can be exploited by breeders for the sustainable deployment of varietal resistance in new cultivars.PostprintPeer reviewe