Biology subjects

Smith, G. C.

Publications and source records attributed to Smith, G. C..

At least 19 recordsLinked to original sources

bioRxiv2026

A novel genetically distinct Amdoparvovirus in Sorex araneus in the United Kingdom highlights an unexplored ancestral link

Amdoparvoviruses have historically been documented almost exclusively in carnivores, with recent detections in bats. However, endogenous viral elements in rodent genomes suggest a more ancient and taxonomically broader evolutionary history. Despite this, small mammals have never been systematically surveyed for extant amdoparvovirus infections. In this study, we used whole genome sequencing to screen four different shrew species and wild American mink in the UK, which may act as a reservoir host for amdoparvoviruses. We identified a highly divergent amdoparvovirus in native common shrews (Sorex araneus) from northern England, tentatively named Shrew parvovirus 1(SP 1). Classical amdoparvovirus sequences were also detected in wild American mink (Neogale vison), confirming the presence of known amdoparvovirus strains in UK mustelids. Phylogenetic analysis revealed that the shrew virus, SP 1, forms a distinct clade, suggesting ancient divergence or long-term cryptic circulation in small mammal reservoirs. These findings fundamentally challenge the hypothesis that amdoparvoviruses are carnivore-restricted pathogens and underscore the importance of systematic wildlife surveillance for understanding viral host range evolution and assessing spillover risks.

evolutionary biology↗

bioRxiv2025

Identifying and prioritising conflicts between human and wildlife interests in Great Britain

O_LIA literature review was conducted to identify human-wildlife conflicts associated with British terrestrial mammal species. Conflicts were classified as economic, health, environmental or social, divided into 32 subcategories, and ranked using a Generic Impact Scoring System (GISS). C_LIO_LIWe identified 48 species associated with 200 conflicts. Sika deer were involved in the most conflicts. The highest ranked conflicts were measurable on an economic scale (involving rabbits, badgers, brown rats, grey squirrels), with the total estimated cost of all economic conflicts exceeding {pound}0.5 billion. C_LIO_LIThe most common conflicts were reservoirs of disease and zoonotic disease, with non-native species scoring statistically higher than native species for the latter. Generally, we scored these conflicts low, deemed localised and mild, but highlighted the importance of surveillance to monitor and control disease spread. C_LIO_LIMost species caused minimal conflict, likely due to their limited distribution. We identified potential impact increased as a function of biomass and population size, therefore a GISS may help identify species capable of expanding beyond their current range, such as recently reintroduced beavers. C_LIO_LIA GISS is useful for identifying conflict species but there is also the need to understand the value of British wildlife. We identified costs-to-benefits trade-offs for several high impact species, including rabbits, deer, badgers and foxes, which underlie human-conflict and/or coexistence and are critical for informed decision-making. As one in four British mammal species face local extinction, the emphasis should encourage focus away from conflict resolution to acceptance and/or tolerance where wildlife and people coexist. C_LI

ecology↗

bioRxiv2025

Predicting the distribution of common wild mammal species across Europe - are there sufficient occurrence data?

ContextKnowledge of where wildlife species are and in what number is critical to support robust contingency planning for diseases affecting animal and human health. For common widespread species in particular, comprehensive surveillance is impractical and challenging to coordinate. This is where models can be useful, to fill in the gaps and direct survey efforts to maximise understanding. The ENETWILD project was commissioned by EFSA in 2017 to review available data and modelling methods to predict distributions for key species involved in diseases of concern (e.g., wild boar and African swine fever). Here, we outline the latest methodology to predict species distributions based on occurrence data and outline the areas where further data would be most helpful. MethodWe present a generic framework to model the distribution of common mammal species in Europe, using global data. Based on occurrence records from large scale repositories, our method first attempts to address known biases to produce a presence-absence dataset and then applies random forest modelling to predict habitat suitability. We apply this approach to twelve species spanning distinct survey methodologies within mammal recording (visual observation, trapping, and bats/audio monitoring). ResultsModel performance was acceptable across all species within the limits of the available training data (AUC close to or above 0.7). However, beyond these limits the reliability of prediction was substantially reduced. Assessment of the available data suggested large areas of Eastern and Southern (particularly mountainous) parts of Europe have a distinct environmental signature not sufficiently captured by the existing sampling. ConclusionsWithin Europe there remain environmental conditions which are not well represented by existing surveillance, predominantly in Eastern and Southern regions. To reliably apply a robust modelling approach to a Europe-wide context targeted data collection is required.

ecology↗

bioRxiv2025

Bovine tuberculosis model validation against a field study of badger vaccination with selective culling

Bovine tuberculosis (TB) is a costly disease in Britain and Ireland shared by cattle and badgers (Meles meles), and to reduce the infection in cattle to low levels some form of badger management is considered necessary. We compare the results of a badger field trial where test-positive badgers are culled, and test-negative badgers vaccinated (a TVR approach) with the results of the simulation model originally used to predict the effect of the trial in Northern Ireland. Initial model results depended strongly on whether social perturbation occurred in the badger population following culling, and the field study demonstrated no evidence for such behavior. Here we re-run the model with the initial conditions of the TVR study and with no social perturbation and predict a similar outcome in terms of number of badgers caught, number testing positive, and the substantial decline in prevalence. These results validate our model and demonstrate the utility of such predictive modelling for this disease system. This is particularly important as the UK government moves away from widespread badger culling in England toward more vaccination, as this combined approach gives a more robust method of disease management than just vaccination on its own.

ecology↗

bioRxiv2025

Immune response to co-administration of bovine tuberculosis and contraceptive vaccines in badgers (Meles meles)

Controlling bovine tuberculosis (bTB) in livestock is often hindered by the presence of a wildlife reservoir, such as the Eurasian badger in the UK and Ireland. Vaccinating badgers against bTB can reduce the severity of Mycobacterium bovis infection and potential onwards transmission to cattle, badgers and other species, thus combined with population control might provide additional benefits (and reference models). To evaluate the effects of co-administration of a bTB vaccine (BCG) and a contraceptive vaccine (GonaCon), captive badgers were injected intramuscularly with either BCG only, GonaCon only or BCG+GonaCon (phase 1). The duration of immune response to BCG vaccination and booster vaccination was also evaluated in the BCG only group over a 24-month period (phase 2). The cellular immune responses to purified protein derivatives PPDA and PPDB, used to measure the effects of BCG, did not differ significantly between the BCG only and BCG+GonaCon badgers but were significantly different between the BCG only and GonaCon only badgers. Anti-GnRH antibody titres, quantified to measure the effect of GonaCon, peaked at the first sampling point for the majority of badgers in the GonaCon only and BCG+GonaCon groups. Throughout phase 1, lasting three months post-vaccination, badgers in both GonaCon treatment groups maintained high anti-GnRH antibody titres (1:128,000 or above) that are associated with infertility in this species, with no significant difference between the two GonaCon groups. The immune responses to BCG vaccination in the BCG only badgers (phase 2) were elevated at the first sampling point, approximately three weeks after initial vaccination and booster vaccination, generally declining thereafter. The results from the current study suggest that co-administration of BCG and GonaCon do not have notable deleterious effects on either of the vaccines and that the protective effect of BCG is enhanced by booster vaccination. The protective effects afforded by both vaccines when given together, in terms of reduced disease burden or fecundity, should be determined by further studies.

immunology↗

bioRxiv2024

Voluntary adolescent alcohol exposure does not increase adulthood consumption of alcohol in multiple mouse and rat models

Adolescence is a period of increased risk taking, including increased alcohol and drug use. Multiple clinical studies report a positive relationship between adolescent alcohol consumption and risk of developing an alcohol use disorder (AUD) in adulthood. However, few preclinical studies have attempted to tease apart the biological contributions of adolescent alcohol exposure, independent of other social, environmental, and stress factors, and studies that have been conducted show mixed results. Here we use several adolescent voluntary consumption of alcohol models, conducted across four labs in three institutes and with two rodent species, to investigate the ramifications of adolescent alcohol consumption on adulthood alcohol consumption in controlled, pre-clinical environments. We consistently demonstrate a lack of robust increases in adulthood alcohol consumption. This work highlights that risks seen in both human datasets and other murine drinking models may be due to unique social and environmental factors - some of which may be unique to humans. HIGHLIGHTSO_LIAdolescent drinking-in-the-dark (DID) binge drinking does not increase adulthood consumption in a DID model or a two bottle choice model in male and female SST-Cre:Ai9 mice C_LIO_LIAdolescent pair-housed intermittent access consumption of alcohol does not increase adulthood consumption in an identical adulthood model in male and female C57BL/6J mice C_LIO_LIAdolescent intermittent access to alcohol does not increase adulthood consumption in male and female Wistar or Fischer 344 rats C_LIO_LIThese complementary datasets across murine models, labs and institutions highlight the need to consider human social factors as well as biological factors C_LI

neuroscience↗

bioRxiv2024

MODERATE ALCOHOL CONSUMPTION INDUCES LASTING IMPACTS ON PREFRONTAL CORTICAL SIGNALING IN MICE

Both alcohol use disorder (AUD) and Alzheimers Disease and Related Dementias (ADRD) appear to include disruption in the balance of excitation and inhibition in the cortex, but their potential interactions are unclear. We examined the effect of moderate voluntary binge alcohol consumption on the aged, pre-disease neuronal environment by measuring intrinsic excitability and spontaneous neurotransmission on prefrontal cortical pyramidal (excitatory, glutamatergic) and non-pyramidal (inhibitory, GABAergic) neurons following a prolonged period of abstinence from alcohol in mice. Results highlight that binge alcohol consumption has lasting impacts on the electrophysiological properties of prefrontal cortical neurons. A profound increase in excitatory events onto layer 2/3 non-pyramidal neurons following alcohol consumption was seen, along with altered intrinsic excitability of pyramidal neurons, which could have a range of effects on Alzheimers Disease progression in humans. These results indicate that moderate voluntary alcohol influences the pre-disease environment in aging and highlight the need for further mechanistic investigation into this risk factor. HIGHLIGHTSO_LIModerate voluntary alcohol consumption leads to disruption of prefrontal cortical signaling at protracted ages in both male and female mice C_LIO_LIExcitatory glutamatergic events onto prelimbic cortex GABAergic neurons, but not pyramidal neurons, are increased 6 months following alcohol exposure C_LIO_LIBoth pyramidal neurons and GABAergic neurons show altered intrinsic excitability 6 months following alcohol exposure C_LI

neuroscience↗

bioRxiv2023

Fetally-encoded GDF15 and maternal GDF15 sensitivity are major determinants of nausea and vomiting in human pregnancy

Human pregnancy is frequently accompanied by nausea and vomiting that may become severe and life-threatening, as in hyperemesis gravidarum (HG), the cause of which is unknown. Growth Differentiation Factor-15 (GDF15), a hormone known to act on the hindbrain to cause emesis, is highly expressed in the placenta and its levels in maternal blood rise rapidly in pregnancy. Variants in the maternal GDF15 gene are associated with HG. Here we report that fetal production of GDF15, and maternal sensitivity to it, both contribute substantially to the risk of HG. We found that the great majority of GDF15 in maternal circulation is derived from the feto-placental unit and that higher GDF15 levels in maternal blood are associated with vomiting and are further elevated in patients with HG. Conversely, we found that lower levels of GDF15 in the non-pregnant state predispose women to HG. A rare C211G variant in GDF15 which strongly predisposes mothers to HG, particularly when the fetus is wild-type, was found to markedly impair cellular secretion of GDF15 and associate with low circulating levels of GDF15 in the non-pregnant state. Consistent with this, two common GDF15 haplotypes which predispose to HG were associated with lower circulating levels outside pregnancy. The administration of a long-acting form of GDF15 to wild-type mice markedly reduced subsequent responses to an acute dose, establishing that desensitisation is a feature of this system. GDF15 levels are known to be highly and chronically elevated in patients with beta thalassemia. In women with this disorder, reports of symptoms of nausea or vomiting in pregnancy were strikingly diminished. Our findings support a causal role for fetal derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by pre-pregnancy exposure to GDF15, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

genetics↗

bioRxiv2022

More hot air: measuring the paradox of European ecology conferences

As scientists we cause an above average carbon footprint for work-related travel. International conferences are a common way for us to meet and discuss, and we do not address the environmental costs of these meetings. Knowing the costs might help us to reduce them. Here we estimated the carbon footprint of the last five physical conferences of the European Wildlife Disease Association (EWDA). We obtained the number of participants from each country for those conferences, and along with assumed travel options, commuting, accommodation, meals and printing, estimated the carbon emissions for each conference. The estimate ranged from 155 to 1205 tons CO2 per conference, or 0.7 to 2.4 tons per person. The outlying upper value was due to one joint global conference of the EWDA and the American mother association (WDA), which takes place every eight years. The geocentre was calculated for both the country of origin of the average conference attendants and for the society membership. The former was located in Luxembourg, and the latter near Dusseldorf, Germany, just approximately 170 km to the north. This represents the shortest total distance attendees would travel. Air transport to the conference country was the major source of CO2 emissions (87-97%), and the average distance flown per person increased from 1000 km (2010) to over 2000 km (2018), since later conferences were generally further from the geocentre. The biggest reduction in carbon emissions (up to 100 tons CO2) could therefore be achieved by decreasing air travel. This could be brought about by reducing the overall travel distance to the conference, i.e. a conference location near the membership geocentre, or - by a lesser amount - by encouraging travel to the conference by train or bus, i.e. conference location near good public travel hubs, and by promoting virtual attendance. Minor but yet substantial savings could be made elsewhere (2-6 tons CO2), including providing accommodation in greener hotels located closer to the conference venue and offering vegan/local food as the default option.

scientific communication and education↗

bioRxiv2022

Adolescent binge drinking leads to long lasting changes in cortical microcircuits

Adolescent drug consumption has increased risks to the individual compared to consumption in adulthood, due to the likelihood of long-term and permanent behavioral and neurological adaptations. However, little is known about how adolescent alcohol consumption influences the maturation and trajectory of cortical circuit development. Here, we explore the consequences of adolescent binge drinking on somatostatin (SST) neuronal function in superficial layers of the prelimbic (PL) cortex in male and female SST-Ai9 mice. We find that adolescent drinking-in-the-dark (DID) produces sex-dependent increases in intrinsic excitability of SST neurons, with no change in overall SST cell number, persisting well into adulthood. While we did not find evidence of altered GABA release from SST neurons onto other neurons within the circuit, we found a complementary reduction in layer II/III pyramidal neuron excitability immediately after binge drinking; however, this hypoexcitability rebounded towards increased pyramidal neuron activity in adulthood in females, suggesting long-term homeostatic adaptations in this circuit. Together, this suggests that binge drinking during key developmental timepoints leads to permanent changes in PL microcircuitry function, which may have broad behavioral implications.

neuroscience↗

bioRxiv2022

Somatostatin peptide signaling dampens cortical circuits and promotes exploratory behavior

Somatostatin (SST) neurons in the prelimbic (PL) cortex mediate a variety of behavioral states. However, little is known about the actions of somatostatin peptide signaling in shaping cortical functioning and behavior. Here, we sought to characterize the unique physiological and behavioral roles of the SST peptide in the PL cortex. We employed a combination of ex vivo pharmacologic and optogenetic electrophysiology, in vivo calcium monitoring, and in vivo peptide pharmacology to explore the role of SST neuron and peptide signaling in the mouse PL cortex. Whole-cell slice electrophysiology was conducted in pyramidal and GABAergic neurons in the PL cortex of C57BL/6J and SST-IRES-Cre male and female mice to characterize the pharmacological mechanism of SST signaling. Fiber photometry of GCaMP6f fluorescent calcium signals from SST neurons was conducted to characterize the activity profile of SST neurons during exploration of an elevated plus maze (EPM) and open field test (OFT). We further used local delivery of both a broad SST receptor (SSTR) agonist and antagonist into bilateral PL cortex to test causal effects of SST administration and receptor blockade on these same exploratory behaviors. SSTR activation broadly hyperpolarized layer 2/3 pyramidal neurons in the PL cortex in both male and female mice ex vivo, an effect that was recapitulated with optogenetic stimulation of SST neurons, through both monosynaptic and polysynaptic GABA neuron-mediated mechanisms of action. This hyperpolarization was blocked by pre-application of the SSTR antagonist cyclo-somatostatin (cyclo-SST) and was non-reversible. SST neurons in PL were activated during EPM and OFT exploration, indicating task-related recruitment of these neurons. Lastly, in line with this exploration-related activity profile, SSTR agonist administration directly into the PL enhanced open arm exploration in the EPM, while in vivo administration of an antagonist had no effect. Together, this work describes a broad ability for SST peptide signaling to modulate microcircuits within the prefrontal cortex and related exploratory behaviors.

neuroscience↗

bioRxiv2021

Differentiation of cortical brain organoids and optic nerve-like structures from retinal confluent cultures of pluripotent stem cells

Advances in the study of neurological conditions have been possible due to induced pluripotent stem cell technologies and the generation of neural cell types and organoids. Numerous studies have described the generation of neural ectoderm-derived retinal and brain structures from pluripotent stem cells. However, the field is still troubled by technical challenges, including high culture costs and organoid-to-organoid variability. Here, we describe a simple and economical protocol that reproducibly gives rise to the neural retina and cortical brain regions from confluent cultures of stem cells. The spontaneously generated cortical organoids were isolated and cultured in suspension conditions for maturation and are transcriptionally comparable to organoids generated by other methods and to human foetal cortex. Furthermore, these organoids show spontaneous functional network activity with proteomic analysis and electron microscopy demonstrating the presence of synaptic components and maturity. The generation of retinal and brain organoids in close proximity also enabled their mutual isolation. Further culture of this complex organoid system demonstrated the formation of optic nerve-like structures connecting retinal and brain organoids, which might facilitate the investigation of the mechanisms of neurological diseases of the eye and brain.

neuroscience↗

bioRxiv2020

Phylodynamic analysis of an emergent Mycobacterium bovis outbreak in an area with no previously known wildlife infections

Understanding how an emergent pathogen successfully establishes itself and persists in a previously unaffected population is a crucial problem in disease ecology. In multi-host pathogen systems this problem is particularly difficult, as the importance of each host species to transmission is often poorly characterised, and the epidemiology of the disease is complex. Opportunities to observe and analyse such emergent scenarios are few. Here, we exploit a unique dataset combining densely-collected data on the epidemiological and evolutionary characteristics of an outbreak of Mycobacterium bovis (M. bovis, the causative agent of bovine tuberculosis, bTB) in a population of cattle and badgers in an area considered low-risk for bTB, that has no previous record of either persistent infection in cattle, or of any infection in wildlife. We analyse the outbreak dynamics using a combination of mathematical modelling, machine learning and Bayesian evolutionary analyses. Comparison to M. bovis whole-genome sequences from Northern Ireland confirmed this to be a single introduction of the pathogen from the latter region, with evolutionary analysis supporting an introduction directly into the local cattle population at least six years prior to its first discovery in badgers. Once introduced, the evidence supports M. bovis epidemiological dynamics passing through two phases, the first dominated by cattle-to-cattle transmission before becoming established in the local badger population. These findings emphasise the importance of disease surveillance for early containment of outbreaks, in particular for pathogens not causing immediately evident symptoms in the infected host, and highlight the utility of combining dynamic modelling and phylogenetic analyses for understanding the often complex infection dynamics associated with emergent outbreaks.

ecology↗

bioRxiv2020

DNA methylation is required to maintain DNA replication timing precision and 3D genome integrity

DNA replication timing and three-dimensional (3D) genome organisation occur across large domains associated with distinct epigenome patterns to functionally compartmentalise genome regulation. However, it is still unclear if alternations in the epigenome, in particular cancer-related DNA hypomethylation, can directly result in alterations to cancer higher order genome architecture. Here, we use Hi-C and single cell Repli-Seq, in the colorectal cancer DNMT1 and DNMT3B DNA methyltransferases double knockout model, to determine the impact of DNA hypomethylation on replication timing and 3D genome organisation. First, we find that the hypomethylated cells show a striking loss of replication timing precision with gain of cell-to-cell replication timing heterogeneity and loss of 3D genome compartmentalisation. Second, hypomethylated regions that undergo a large change in replication timing also show loss of allelic replication timing, including at cancer-related genes. Finally, we observe the formation of broad ectopic H3K4me3-H3K9me3 domains across hypomethylated regions where late replication is maintained, that potentially prevent aberrant transcription and loss of genome organisation after DNA demethylation. Together, our results highlight a previously underappreciated role for DNA methylation in maintenance of 3D genome architecture.

molecular biology↗

bioRxiv2020

Nicotinamide mononucleotide (NMN) de-amidation by the gut microbiome and evidence for indirect upregulation of the NAD+ metabolome

Oral administration of nicotinamide mononucleotide (NMN) is a prominent strategy to elevate nicotinamide adenine dinucleotide (NAD+) levels to treat age-related pathologies, where it is assumed to be directly incorporated into the NAD+ metabolome through the canonical recycling pathway. During oral delivery, NMN is exposed to the gut microbiome, which can modify the NAD+ metabolome through enzyme activities that are not present in mammals. Here, we show that orally delivered NMN can undergo direct deamidation and incorporation in mammalian tissue via the de novo pathway, and that this deamidation is reduced in animals treated with antibiotics to ablate the gut microbiome. Further, we show that antibiotics treatment increases the overall availability of NAD+ metabolites in the gut epithelium, with one possibility that the gut microbiome could be in competition with the host for dietary NAD+ precursors. Together, these data highlight previously undescribed interactions between orally delivered NMN and the gut microbiome.

biochemistry↗

bioRxiv2020

Developing methods for measuring national distributions and densities of wild mammals using camera traps: A Kosovo study

Understanding the distributions and density of wild mammals is integral to the implementation of wildlife management strategies, particularly for controlling diseases and conservation management. Recent advances in camera trap technology together with the development of the Random Encounter Model have provided a non-invasive method for estimating mammal densities. In addition, the development of citizen science initiatives have advanced ecological data collection. This study describes a national camera trap survey delivered by local stakeholders in eleven forest sites in Kosovo from 2014 to 2015 to measure the distributions and abundance of medium to large wild mammals as part of the Control and/or eradication of animal diseases project. The Random Encounter Model was used to calculate density data for each species, which appear realistic when compared to densities found in other European countries. The study particularly focussed on the red fox (Vulpes vulpes) and the grey wolf (Canis lupus) as potential vectors of rabies and wild boar (Sus scrofa) as a vector of classical swine fever. These species were found to be three of the most widely distributed species in Kosovo and were present at the majority of sites at high densities. The camera survey also provided information on species of conservation concern such as the Eurasian brown bear (Ursus arctos) and provided the first physical evidence of a live Eurasian golden jackal (Canis aureus) in Kosovo. Although sources of bias were identified, these estimates are likely to be more accurate than those devised from methods such as hunting bags and the findings of this study suggest that, with a moderate amount of development, camera trapping implemented by local stakeholders can be used as an effective and practicable method to estimate national distributions and population sizes of medium to large sized wild mammals.

ecology↗

bioRxiv2019

Running rabid: modelling of European bat lyssavirus (EBLV) pathways in a bat population

Worldwide the 16 species of lyssaviruses all exhibit a similar pathology in most mammals, including man; with successful infections usually ending with death. Recently it has been demonstrated that European bat lyssaviruses (EBLV) are not invariably fatal in their wild reservoir host bat species, however the mechanisms and epidemiological consequences of this resistance are interesting and unexplored and the fundamental pathology in bats is still unclear. Here we modelled alternative pathological pathways to explore which appear most plausible, with respect to our limited knowledge of bat-rabies epidemiology and also host population dynamics. Two models were created, one based on a standard progression of disease (classic SEIR model) and the other modified to allow for animals to become either rabid or immune (flexible model). Of these our flexible model was found to be more plausible, demonstrating a much lower sensitivity to epidemiological parameters and by inference the more likely to represent the real-life process occurring in wild European bat populations, with a comparative state space ratio of 1:47. This result implies that it is highly probable survival and post-infection immunity is a widespread epidemiological phenomenon rather than an infrequent consequence of an aborted infection in few individuals. These results can be used to inform laboratory studies on bat immunology and future bat modelling work.

ecology↗

bioRxiv2019

Structuring the unstructured: estimating species-specific absence from multi-species presence data to inform pseudo-absence selection in species distribution models

O_LISpecies distribution models (SDMs) are an increasingly popular tool in ecology which, together with a vast wealth of data from citizen science projects, have the potential to dramatically improve our understanding of species behaviour for applications such as conservation and wildlife management. However, many of the best performing models require information regarding survey effort, specifically absence, which is typically lacking in opportunistic datasets. To facilitate the use of such models, pseudo-absences from locations without recorded presence must be assumed. Several studies have suggested that survey effort, and hence likely absence, could be estimated from presence-only data by considering records across \"target groups\" of species defined according to taxonomy.\nC_LIO_LIWe performed a probabilistic analysis, computing the conditional probability of recording a species given a particular set of species are also recorded, to test the validity of defining target groups by taxonomic order and to explore other potential groupings. Based on this quantification of recording associations we outline a new method to inform pseudo-absence selection comparing predictive performance, measured the area under curve (AUC) statistic, against the standard method of selection across a series of SDMs.\nC_LIO_LIOur findings show some support for target grouping classification based on taxonomy but indicate that an alternative classification using survey method may be more appropriate for informing effort and consequently absence. Across 49 terrestrial mammal species, pseudo-absence selection using our proposed method outperformed that of the standard method showing an improvement in the predictive performance of presence-absence models for 17 out of 22 with sufficient data to elicit a significant difference. Based on our method we also observed a substantial improvement in the performance of presence-absence models compared to that of presence-only models (MaxEnt) with a higher AUC for all 22 species showing a significant difference between approaches.\nC_LIO_LIWe conclude that our method produces sensible robust pseudo-absences which either compliment patterns in known presences or, where conflicts occur, are explainable in terms of ecological variables potentially improving our understanding of species behaviour. Furthermore, we suggest that presence-absence models using these pseudo-absences provide a viable alternative to MaxEnt when modelling using presence-only data.\nC_LI

ecology↗