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SituationPharmacists are fundamental components of the neonatal workforce and should have job plans with protected capacity for providing advice and support in neonatal pharmacy.1Using Neonatal and Paediatric Pharmacists Group staffing recommendations2a shortfall of 0.675 whole time equivalent (wte) band 8a pharmacist resource was identified. A business case was developed and funding was approved to increase the existing neonatal pharmacist’s input to the neonatal intensive care unit (NICU) from 0.325 wte to 1 wte from June 2021. The main driver was the number of medication incidents reported, particularly involving gentamicin. Prior to June 2021 the neonatal pharmacist was part of a multi-disciplinary task and finish group established to reduce medication, especially gentamicin, errors. A detailed action plan and a new gentamicin guideline and prescription were developed which included significant training and teaching of both medical and nursing staff. A review of all gentamicin errors reported electronically via Datix from June 2019 to June 2022 was undertaken. A reduction in gentamicin errors was achieved prior to June 2021 and was successfully sustained up to June 2022.Also feedback was sought from a multi-disciplinary team to ascertain the impact of increased pharmacist resource. The following improvements were identified:Sustained improvement in other medication related incidents.Bedside teaching for nursing and junior medical staffPharmacist attendance at handover and on ward rounds.Co-operative decision making on neonatal treatments in real time with consultants.Pharmacist prescribing.Development of guidelines, prescribing proformas and prescription charts.Communication between pharmacists in network providing peer support.Support with unlicensed medicines and drug shortages.Support in neonatal governance, perinatal mortality review and palliative care.Safety improvements in storage, transport, and use of resuscitation medications.Support with discharge and community follow up of medication challenges.ConclusionThe role of the neonatal pharmacist is pivotal to ensuring safe and effective use of medicines on a NICU. A key element of the role is to provide training and support to medical and nursing staff to ensure medication safety and utilisation is followed. Sustenance in quality improvement is a well-recognised challenge in health-care settings which was achieved as a likely result of increased pharmacy presence. The improvements identified all contribute to improved patient safety. This may be further improved by the development of standard prescription charts, guidelines, and drug formulary, across the local network or nationally.ReferencesDepartment of health. Toolkit for high quality Neonatal services. October 2009. Available at: Toolkit for High-Quality Neonatal Services (londonneonatalnetwork.org.uk)Neonatal and Paediatric Pharmacists Group. Neonatal Pharmacy staffing on Neonatal Units – Recommendations for Trusts Commissioning. October 2018. Available at: http://www.nppg.org.uk/wp-content/uploads/2018/10/NPPG-Neonatal-Pharmaciststaffing-recommendations-published-with-RPS-Oct-2018.pdf

Background In England, neonatal care is delivered in operational delivery networks, comprising a combination of the Neonatal Intensive Care (NICU), Local-Neonatal (LNU) or Special-Care Units (SCU), based on their ability to care for babies with different degrees of illness or prematurity. With the development of network care pathways, the most premature and sickest are mostly triaged for delivery in services linked to NICU. This has created anxiety for teams in LNU and SCU. Less exposure to sicker babies has resulted in limited opportunities to maintain expertise for when these babies unexpectedly deliver at their centre and thereafter require transfer for care, to NICU. Simultaneously, LNU and SCU teams develop skills in the care of the less ill and premature baby which would also be of benefit to NICU teams. A need for mutual learning through inter-unit multidirectional collaborative learning and engagement (hereafter also called neonatal networking) between teams of different designations emerged. Here, neonatal networking is defined as collaboration, shared clinical learning and developing an understanding of local systems strengths and challenges between units of different and similar designations. We describe the responses to the development of a clinical and systems focussed platform for this engagement between different teams within our neonatal ODN. Method An interactive 1-day programme was developed in the West Midlands, focussing on a non-hierarchical, equal partnership between neonatal teams from different unit designations. It utilised simulation around clinical scenarios, with a slant towards consultant engagement. Four groups rotating through four clinical simulation scenarios were developed. Each group participated in a clinical simulation scenario, led by a consultant and supported by nurses and doctors in training together with facilitators, with a further ~two consultants, as observers within the group. All were considered learners. Consultant candidates took turns to be participants and observers in the simulation scenarios so that at the end of the day all had led a scenario. Each simulation-clinical debrief session was lengthened by a further ~ 20 min, during which freestyle discussion with all learners occurred. This was to promote further bonding, through multidirectional sharing, and with a systems focus on understanding the strengths and challenges of practices in different units. A consultant focus was adopted to promote a long-term engagement between units around shared care. There were four time points for this neonatal networking during the course of the day. Qualitative assessment and a Likert scale were used to assess this initiative over 4 years. Results One hundred fifty-five individuals involved in frontline neonatal care participated. Seventy-seven were consultants, supported by neonatal trainees, staff grade doctors, clinical fellows, advanced neonatal nurse practitioners and nurses in training. All were invited to participate in the survey. The survey response rate was 80.6%. Seventy-nine percent felt that this learning strategy was highly relevant; 96% agreed that for consultants this was appropriate adult learning. Ninety-eight percent agreed that consultant training encompassed more than bedside clinical management, including forging communication links between teams. Thematic responses suggested that this was a highly useful method for multi-directional learning around shared care between neonatal units. Conclusion Simulation, enhanced with systems focussed debrief, appeared to be an acceptable method of promoting multidirectional learning within neonatal teams of differing designations within the WMNODN.

Background: In England neonatal care is delivered within operational delivery networks. Units within these networks are one of three designations (Neonatal Intensive Care, Local-Neonatal or Special-Care Units), based on their ability to care for babies with different degrees of illness or prematurity. With the development of network care-pathways, the most premature and sickest are triaged where possible for delivery in services linked to Neonatal Intensive Care units. This has created anxiety for teams in Local-Neonatal and Special-Care units. Less exposure to sicker babies meant limited opportunities to maintain expertise for when they do unexpectedly deliver at services linked to their own units, and thereafter require transfer for ongoing care, to Neonatal Intensive Care units. Simultaneously, Local-Neonatal and Special-Care teams develop skills in care of the less ill and premature baby which was considered of benefit to all. A need for mutual learning through networking between teams of different designations emerged.Method: An interactive programme, ‘Supporting The Sick Neonate’ was developed in the West Midlands. It focused on equal partnership between unit designations, employing high, medium and low fidelity simulation as the vehicle around which networking between units was centered. Sessions of simulation and debrief were augmented with novel networking time to enable multidirectional learning and understanding of practices. Candidates and facilitators were regarded as participants, spanning different designations. A consultant-focus was adopted to promote long term networking. Qualitative assessment of the programme over four years was captured through -graded and free text surveys.Results: 155 individuals involved in frontline neonatal care participated. 77 were consultants, supported by neonatal trainees, staff grade doctors, clinical fellows, advanced neonatal nurse practitioners and nurses in training. All were invited to participate in the qualitative survey. 79% felt that it was highly relevant; 96% agreed that for consultants this was appropriate adult learning. 98% agreed that consultant training encompassed more than bedside clinical management, including forging communication links between teams. Thematic responses around networking were positive.Conclusion: Simulation augmented with networking time with a consultant-focused model proved successful for networking and shared learning for the Neonatal fraternity in the West Midlands.

Von Willebrand Disease (VWD) is the most common bleeding disorder. In addition to known major genes, genetic modifiers, such as ABO blood group, affect quantitative outcome measures for VWD. To study genetic modification of VWD, an 854-member Amish pedigree with established linkage of VWD to a known mutation in the Von Willebrand Factor (VWF) gene on chromosome 12 was utilized. Phenotypic information and genotypic data consisting of VWF mutation status and a genome screen of markers were available for 385 pedigree members. Genetic modifiers of the VWF mutation were investigated using known and new conditional linkage methods that search for modifier genes of a major gene with known mutation. The MCMC-based program LOKI (Heath, 1997) was used to conduct multipoint linkage analysis of VWD outcome measures while controlling for the known VWF mutation. Adjustment for the mutation did not eliminate the linkage signal on chromosome 12 in the same location as the VWF mutation. Evidence for quantitative trait loci (QTLs) was also found on six other chromosomes. Smod, a score statistic that detects evidence of a genetic modifier conditional on linkage to a major gene, was developed for sib pair data. To limit the modifier gene main effect, Smod was developed so that variance due to the modifier locus was bounded above by the variance of the interaction between major gene and modifier gene. The performance of Smod was compared to other published score statistics. Power to detect linkage to the modifier locus depended on major gene and modifier gene risk allele frequencies, relative contribution of the major gene main effect to the interaction effect, and the upper bound on the modifier gene main effect. The Amish pedigree was broken up into sib pair data and analyzed using Smod and other score statistics. Using these statistics, the strongest evidence for QTLs for VWD

The timing and duration of sexual brood production in ants can affect their rate of spread and colony growth. Because protein is key to larval growth, queen survival and fecundity, macronutrient collection by foraging workers is expected to favour protein prior to and throughout gyne production. However, food preference driven by the production of gynes may be overridden by a preference associated with worker production, especially if investment in workers vastly outweighs that of sexual brood and workers are produced on different schedules. Food preferences alone may not indicate the availability of that food type in the environment. On Christmas Island, Indian Ocean, sexual brood of the invasive Yellow Crazy Ant, Anoplolepis gracilipes (Smith, 1857), was produced annually during a single period associated with the onset of the wet season. However, workers were produced continuously throughout the year and colony investment to worker production measured by the standing biomass of eggs, larvae and pupae, typically exceeded 98%. High, aseasonal investment in worker production, together with aseasonal worker activity, would suggest that there should be no seasonal preference shown by workers at food stations containing both protein and carbohydrate. However, workers showed a preference for one food type over another on 46 of 61 occasions at one site and on 31 of 41 occasions at another. When a preference was shown, it was predominantly for protein-rich food during the dry season and almost always for carbohydrate at the onset and during the wet season. We suggest that these preferences reflect seasonal shortages in key resources when invertebrates (protein-rich) are scarce during the dry season and honeydew from scale insects (carbohydrate) is depleted by rain during the wet season. On Christmas Island, timing and duration of the dry season preference for protein has been exploited by the control program for A. gracilipes supercolonies, which deploys a toxin in a proteinaceous bait matrix during dry periods.

Populations of invasive species are often studied when their effects are perceived as a problem. Yet observing the dynamics of populations over longer time periods can highlight changes in effects on invaded communities, and assist with management decisions. In this study we revisit an invasion of the yellow crazy ant (Anoplolepis gracilipes) in the Tokelau archipelago to determine if the distribution and abundance of the ant has changed ~7 years after surveys completed in 2004. We were particularly interested in whether populations of a previously identified invasive haplotype (D) had increased in distribution and abundance, as this haplotype was implicated in negative effects on resident ant communities. Indeed, haplotype D populations have become more widespread since the initial survey, more likely owing to new introductions or movement by humans, rather than intrinsic characteristics of the haplotype. We also found that despite no significant change in the abundance of A. gracilipes overall, haplotype D populations have declined in abundance. Residents of the Tokelau atolls no longer consider the ant to be a pest as they did 7 years ago, when populations of this ant interfered with their food production and many other aspects of daily life. We observed no significant differences between A. gracilipes invaded and uninvaded communities, which suggests that the ant is at a level of abundance below which significant negative ecological effects may occur. Population declines of invasive species are not infrequent, and understanding these population dynamics, particularly the underlying mechanisms promoting population declines or stabilisation, should be a high priority for invasion ecology.

Invasive species can dramatically alter trophic interactions. Predation is the predominant trophic interaction generally considered to be responsible for ecological change after invasion. In contrast, how frequently competition from invasive species contributes to the decline of native species remains controversial. Here, we demonstrate how the trophic ecology of the remote atoll nation of Tokelau is changing due to competition between invasive ants (Anoplolepis gracilipes) and native terrestrial hermit crabs (Coenobita spp.) for carrion. A significant negative correlation was observed between A. gracilipes and hermit crab abundance. On islands with A. gracilipes, crabs were generally restricted to the periphery of invaded islands. Very few hermit crabs were found in central areas of these islands where A. gracilipes abundances were highest. Ant exclusion experiments demonstrated that changes in the abundance and distribution of hermit crabs on Tokelau are a result of competition. The ants did not kill the hermit crabs. Rather, when highly abundant, A. gracilipes attacked crabs by spraying acid and drove crabs away from carrion resources. Analysis of naturally occurring N and C isotopes suggests that the ants are effectively lowering the trophic level of crabs. According to delta(15) N values, hermit crabs have a relatively high trophic level on islands where A. gracilipes have not invaded. In contrast, where these ants have invaded we observed a significant decrease in delta(15) N for all crab species. This result concurs with our experiment in suggesting long-term exclusion from carrion resources, driving co-occurring crabs towards a more herbivorous diet. Changes in hermit crab abundance or distribution may have major ramifications for the stability of plant communities. Because A. gracilipes have invaded many tropical islands where the predominant scavengers are hermit crabs, we consider that their competitive effects are likely to be more prominent in structuring communities than predation.

Positive interactions play a widespread role in facilitating biological invasions. Here we use a landscape-scale ant exclusion experiment to show that widespread invasion of tropical rainforest by honeydew-producing scale insects on Christmas Island (Indian Ocean) has been facilitated by positive interactions with the invasive ant Anoplolepis gracilipes. Toxic bait was used to exclude A. gracilipes from large (9-35 ha) forest patches. Within 11 weeks, ant activity on the ground and on trunks had been reduced by 98-100%, while activity on control plots remained unchanged. The exclusion of ants caused a 100% decline in the density of scale insects in the canopies of three rainforest trees in 12 months (Inocarpus fagifer, Syzygium nervosum and Barringtonia racemosa), but on B. racemosa densities of scale insects also declined in control plots, resulting in no effect of ant exclusion on this species. This study demonstrates the role of positive interactions in facilitating biological invasions, and supports recent models calling for greater recognition of the role of positive interactions in structuring ecological communities.

The Argentine ant is native to South America and has spread widely across the globe. In this study, we use genetic analyses and behavioural assays to examine the colony structure of Argentine ants in New Zealand. Diet modification studies were also carried out in order to help identify what factors influence these behavioural assays. There was no aggression observed between any pairings tested across the North Island of New Zealand, though we found that diet manipulations in the laboratory could lead to low levels of aggression between previously amiable Argentine ant nests. The New Zealand population of Argentine ants was characterized by low levels of genetic variation in six microsatellite loci from their nuclear genome. Additionally, the population also lacked significant genetic structuring with no patterns of regional differentiation or isolation by distance. An analysis of molecular variation(AMOVA) found that themajority of genetic variation was present at a nest level (93% of total genetic variance), with little genetic differentiation observed within or between regions (3 – 4% of total genetic variance). No correlation between aggression and genetic relatedness was observed. This evidence suggests that Argentine ants in New Zealand effectively form a unicolonial population, which is likely the result of colonization from a single source population. As far as we know, this is the first country to have an entirely unicolonial population of Argentine ants.

Ant invasions exert a range of effects on recipient communities, from displacement of particular species to more complex community disruption. While species loss has been recorded for a number of invasion events, a little examined aspect of these invasions is the mechanisms for coexistence with resident ant species.The yellow crazy ant, Anoplolepis gracilipes (Smith), is considered one of the world’s worst ant invaders and has recently undergone rapid population growth in Tokelau. We surveyed the ground-dwelling ant fauna in two plots on each of five invaded and three uninvaded islands across two atolls in Tokelau to examine community characteristics of the ant fauna in areas with and without yellow crazy ants. We also used three types of food bait (tuna, jam and peanut butter) to experimentally test if species are able to coexist by consuming different food resources. Anoplolepis gracilipes was found to coexist with two to six other ant species at any one site, and coexisted with a total of 11 ant species. Four species never co-occurred with A. gracilipes. Non-metric multidimensional scaling showed significant differences in community composition and the relative abundance of species between areas that had, and had not, been invaded by A. gracilipes. The number of other ant species was significantly lower in communities invaded by the yellow crazy ant, but did not decline with increasing A. gracilipes abundance, indicating that impacts were independent of population density. The yellow crazy ant dominated all tuna and jam baits, but had a low attendance on peanut butter, allowing four other ant species to access this resource. Our results demonstrate community level impacts of an ant invader on a tropical oceanic atoll and suggest that differing use of food resources can facilitate coexistence in ant communities.

In this paper we describe how digital technologies can be used to enhance collaboration and student engagement in a large, multicampus undergraduate science unit. Four innovations developed and implemented over a period of eight years are described: use of electronic whiteboards, on-line discussion forums, social media and blogs. In showing the intermediate steps in the evolution of the use of digital and communication technologies, we demonstrate that to be effective, good educational principles are paramount.

Populations of invasive species often exhibit a high degree of spatial and temporal variability in abundance and hence their effects on resident communities. Here, we examine behavioural, genetic and environmental factors that influence variation in populations of the yellow crazy ant, Anoplolepis gracilipes, on the remote Nukunonu Atoll of Tokelau, Pacific Ocean. Behavioural assays revealed high levels of aggression between two groups of yellow crazy ants from different islands, and genetic analysis confirmed the presence of two distinct populations with unique mitochondrial (mt)DNA haplotypes, designated A and D. The two populations likely resulted from two separate invasion events. The populations exhibited significant differences in abundance of A. gracilipes, with a mean sevenfold difference in relative abundance between the two main haplotypes. The higher density haplotype D population coexisted with 50% fewer other ant species and altered ant community composition. Vegetation composition was also significantly different on islands harbouring the two populations. The results suggest genetic differences could play a role in the spatial and temporal variation in the effect of the yellow crazy ant on a small oceanic atoll. We could not differentiate between genetic effects and effects of vegetation. However, our results indicate that spatial variability in behaviour and impacts within populations of invasive species could be in part due to genetic differences, and play a substantial role in influencing the outcome of biological invasions.

This paper combines published and new collection records to provide a comprehensive list of ant species collected on Tokelau, a Pacific is- land nation with the world's smallest land area. Twenty-eight ant species have been recorded since the late 1950s, 10 in recent surveys, and the majority of which are tramp species. Known invasive spe- cies such as Anoplolepis gracilipes, Monomorium pharaonis, Pheidole megacephala, and Tapinoma melanocephalum are present but currently appear to have a limited distribution on two of the three atolls. There are no ant species endemic to Tokelau, but two Pacific endemics, and 11 Pacific natives; 26 listed ant species are present in Samoa, which is the likely point of origin for most of Tokelau's ant fauna. Pit- fall trap collections from three visits between 2002 and 2005 highlight how different sampling intensi- ties and locations alter the species accumulation rate and species richness and diversity estimates. The relationship between total ant species and land area of Pacific islands is linear, but combined with earlier records, this study reports more ant species from Tokelau than the analysis predicts. This study indicates the remote and small nation of Tokelau is as susceptible to invasive species as other larger, more populated, land masses in the Pacific.

Key to the management of invasive species is an understanding of the scope of an invasion, the rate of proliferation and the rate at which invaded habitats become degraded. This study examines the spatial dynamics of high-density supercolonies of the invasive yellow crazy ant, Anoplolepis gracilipes, on Christmas Island, Indian Ocean, and the associated impacts at their boundaries. Since the early 1990s, A. gracilipes supercolonies have occupied over 30% of the 10,000 ha of rainforest on Christmas Island. Thirty-four discrete high-density supercolonies formed between 1989 and 2003, ranging in size across nearly three orders of magnitude from 0.9 to 787 ha. Supercolonies boundaries are diffuse, and ants were observed in low densities in some cases up to 200 m from the main high-density supercolony. The 13 boundaries examined were all dynamic over a 10-20 observation month period: nine boundaries expanded, and the maximum rate of spread was 0.5 m day -1 . Across boundary transition zones, between high-density supercolonies and intact rainforest, yellow crazy ants reduced other ant species richness, occupied red crab burrows and killed resident red crabs, which was the trigger for 'invasional meltdown' on Christmas Island. The highly variable and unpredictable nature of A. gracilipes boundaries poses a challenge for incorporation into a predictive framework, as well as for their management.

Ants have the capacity to reach unusually high densities, mostly in their introduced ranges. Numerical dominance is often cited as key to the ability of exotic ants to displace native ant species, reduce the abundance of invertebrates and negatively impact upon bird, land crab and other vertebrate populations. On Christmas Island, Indian Ocean, the yellow crazy ant, Anoplolepis gracilipes (Jerdon), forms supercolonies, where extremely high densities of foraging ants have contributed to ‘invasional meltdown’ in rainforest areas. Densities of up to 2254 foraging ants per m2 and a biomass of 1.85 g per m2 were recorded, and nest densities reached 10.5 nest entrances per m2. Populations of A. gracilipes can overcome and kill red endemic land crabs (Gecarcoidea natalis) over 100 times their own biomass. This is the highest recorded density of foraging ants, and adds another element to the definition of ‘supercolony’ of unicolonial ants. This paper documents one extreme in a continuum of densities of unicolonial, invasive ant species and highlights the need to incorporate forager densities into invasive ant research.

Neonatal cerebral abscess is a rare but serious complication of sepsis, with high mortality and morbidity. We present a case of enterobacter cerebral abscesses in a 26+1-week gestation infant with birth weight of 850 g, managed conservatively. Baby A was born in poor condition after prolonged rupture of membranes, requiring full resuscitation. He developed profound sepsis with blood cultures positive for Enterobacter cloacae at 12 hours. First-line antibiotics (benzylpenicillin and gentamicin) were changed to meropenem. Serial cranial ultrasound scans showed …

Recent research has investigated the relationship between personality and social support in predicting various forms of adjustment. This study explores this relationship in a sample of 137 human service professionals engaged in post-degree clinical skills training at the Christian Counselling Centre in Vellore, India. The impact of certain forms of social support on burnout was examined, after controlling for the effect of the personality trait of anxiety. As hypothesized, perceived social support was negatively associated with burnout, even after controlling for the effects of anxiety. This pattern was strongest for the males in this sample. Emotional exhaustion and depersonalization were the components of burnout most strongly related to perceived support. The perception of support received from ‘work-related’ and ‘other’ relationships made a stronger contribution than did ‘family’ or ‘social’ ties with respect to burnout. Implications for future cross-cultural investigation of the relationships among personality, social support and adjustment are discussed. Copyright © 2003 John Wiley & Sons, Ltd.

In multiply invaded ecosystems, introduced species should interact with each other as well as with native species. Invader-invader interactions may affect the success of further invaders by altering attributes of recipient communities and propagule pressure. The invasional meltdown hypothesis (IMH) posits that positive interactions among invaders initiate positive population-level feedback that intensifies impacts and promotes secondary invasions. IMH remains controversial: few studies show feedback between invaders that amplifies their effects, and none yet demonstrate facilitation of entry and spread of secondary invaders. Our results show that supercolonies of an alien ant, promoted by mutualism with introduced honeydew-secreting scale insects, permitted invasion by an exotic land snail on Christmas Island, Indian Ocean. Modeling of land snail spread over 750 sites across 135 km2 over seven years showed that the probability of land snail invasion was facilitated 253-fold in ant supercolonies but impeded in intact forest where predaceous native land crabs remained abundant. Land snail occurrence at neighboring sites, a measure of propagule pressure, also promoted land snail spread. Site comparisons and experiments revealed that ant supercolonies, by killing land crabs but not land snails, disrupted biotic resistance and provided enemy-free space. Predation pressure on land snails was lower (28.6%), survival 115 times longer, and abundance 20-fold greater in supercolonies than in intact forest. Whole-ecosystem suppression of supercolonies reversed the probability of land snail invasion by allowing recolonization of land crabs; land snails were much less likely (0.79%) to invade sites where supercolonies were suppressed than where they remained intact. Our results provide strong empirical evidence for IMH by demonstrating that mutualism between invaders reconfigures key interactions in the recipient community. This facilitates entry of secondary invaders and elevates propagule pressure, propagating their spread at the whole-ecosystem level. We show that identification and management of key facilitative interactions in invaded ecosystems can be used to reverse impacts and restore resistance to further invasions.

Background The relative importance of chance and determinism in structuring ecological communities has been debated for nearly a century. Evidence for determinism or assembly rules is often evaluated with null models that randomize the occurrence of species in particular locales. However, analyses of the presence or absence of species ignores the potential influence of species abundances, which have long been considered of major importance on community structure. Here, we test for community assembly rules in ant communities on small islands of the Tokelau archipelago using both presence-absence and abundance data. We conducted three sets of analyses on two spatial scales using three years of sampling data from 39 plots on 11 islands. Results First, traditional null model tests showed support for negative species co-occurrence patterns among plots within islands, but not among islands. A plausible explanation for this result is that analyses at larger spatial scales merge heterogeneous habitats that have considerable effects on species occurrences. Second, analyses of ant abundances showed that samples with high ant abundances had fewer species than expected by chance, both within and among islands. One ant species, the invasive yellow crazy ant Anoplolepis gracilipes, appeared to have a particularly strong effect on community structure correlated with its abundance. Third, abundances of most ant species were inversely correlated with the abundances of all other ants at both spatial scales. This result is consistent with competition theory, which predicts species distributions are affected by diffuse competition with suites of co-occurring species. Conclusion Our results support a pluralistic explanation for ant species abundances and assembly. Both stochastic and deterministic processes interact to determine ant community assembly, though abundance patterns clearly drive the deterministic patterns in this community. These deterministic patterns were observed at two spatial scales. Results indicate that abundance-based null models may be more sensitive in detecting non-random patterns in community assembly than species co-occurrences analyses.