General and Comparative Endocrinology

Corazonin is implicated in regulating diverse behavioral and physiological responses in insects, yet its role in honey bees remains unclear. Work in social and non-social species suggests an ancestral function for corazonin as a metabolic stress signal and a derived function as a pro-foraging signal in social insects. To investigate this hypothesis, we examined corazonin signaling across worker roles and metabolic states and tested its regulatory relationships with pathways central to worker division of labor. Central corazonin levels (both transcript and peptide) were approximately threefold higher in foragers than in nurses. Acute metabolic challenge did not alter brain corazonin but strongly upregulated fat body corazonin receptor (CrzR) transcript in nurses only, suggesting role-specific induction of peripheral sensitivity to corazonin signaling. Injection of synthetic corazonin decreased fat body insulin receptor substrate transcript, while transcripts of vitellogenin (Vg), unpaired-like A, ecdysone receptor B, and Cyp314a1 were unaffected. Measures of gustatory responsiveness, starvation resistance, and hemolymph sugar levels were similarly unaffected by corazonin injection. Reducing Vg through RNA interference in nurse-age bees did not affect CrzR transcript levels, despite vitellogenin's established roles in stress buffering, antioxidant defense, and lifespan. This contrast highlights the specificity of CrzR upregulation in nurses as a response to metabolic challenge rather than general stress. Together, these findings support corazonin as a co-opted nutritional signal that helps shape the forager physiological state, suggesting that it may act in part through interactions with insulin signaling rather than directly regulating classical nutritional or stress-response pathways.

Progesterone governs the establishment and maintenance of pregnancy in ruminants, acting through the nuclear progesterone receptor (PGR) and, potentially, through membrane progesterone receptors (mPRs) of the PAQR family. The cellular distribution of mPRs in ruminant reproductive tissues, however, remains undefined. We generated and validated rabbit polyclonal antibodies against the intracellular C-terminal peptides of bovine PAQR6 (mPR{delta}) and PAQR8 (mPR{beta}), and used them, with quantitative PCR of the uterus and conceptus, to map these receptors in the ovine uterus and conceptus and in the bovine ovary. Both antisera showed high ELISA titer against their immunizing peptides, negligible preimmune reactivity, and complete loss of tissue signal after peptide pre-absorption. By qPCR, PAQR6, PAQR8 and PGR transcript levels did not change significantly across the peri-implantation period in either the conceptus or the endometrium; in contrast, the progesterone-responsive gene ZBTB16 increased markedly in the conceptus (up to ~45-fold by day 21, p < 0.05 at days 17, 19 and 21), whereas FKBP5 showed a numerical increase without reaching statistical significance. Both genes remained relatively stable in the endometrium, indicating conceptus-specific changes in progesterone-responsive gene expression. At the protein level, PAQR6 and PAQR8 localized to the luminal and glandular epithelium of the endometrium across the cycle and early pregnancy, and to follicular (granulosa) and luteal cells of the ovary. Dual immunofluorescence in the ovine endometrium showed that both PAQR6 and PAQR8 are enriched at the apical surface of the luminal epithelium and are spatially distinct from the basolateral adherens-junction marker E-cadherin. These results provide a protein-level map of PAQR6 and PAQR8 in the ruminant reproductive tract, identify the apical epithelial surface as a site of receptor enrichment, and show that the endometrial epithelium retains membrane progesterone receptors while progesterone-responsive gene expression changes dynamically in the conceptus during the peri-implantation period. The validated ruminant-reactive antibodies provide a resource for future functional studies.

Developing in suboptimal temperatures can have widespread negative effects in organisms, but early exposure to thermal challenges can also trigger increased investment in thermoregulatory capacity. Within birds, the effects of cold exposure during incubation may differ between precocial and altricial species due to differences in the ontogeny of thermoregulation. To date, most of the evidence showing that embryonic cold exposure shapes future thermoregulatory capacity comes from a few precocial species in laboratory settings. Less is known about sensitivity to low-temperature incubation in altricial species which only become fully endothermic after hatching. In this study, we tested the effects of cold temperatures during embryonic development by temporarily cooling the nest boxes of free-living tree swallows (Tachycineta bicolor) during late incubation and subsequently exposing nestlings to an acute cold challenge. Cold exposure during early development made nestlings better at maintaining their body temperatures during the acute challenge. Developmentally cold-exposed birds also had higher thyroxine (T4) levels when sampled at lower ambient temperatures, whereas control birds showed the opposite relationship. Among nestlings that failed to maintain their body temperature during the acute cold challenge, developmentally cold-exposed nestlings secreted more corticosterone during the acute cold challenge than control nestlings. Despite these changes, cold-exposed birds did not differ from controls in cold-induced metabolic rates, body mass, or bacteria killing ability. These results are, to our knowledge, the first to show that developmental cold exposure increases the capacity to maintain body temperature during future cold challenges in a songbird. These findings suggest that experiencing even a mild decline in ambient temperatures during embryonic development could prime birds to cope more effectively with harsh or variable environmental conditions later in life.

Vertebrates cope with rapid temperature fluctuations by plastically adjusting their behaviour and physiology. This phenotypic plasticity is partly mediated by plastic changes in glucocorticoid levels; however, whether individual differences in endocrine plasticity are associated with fitness remains unknown. Here, we examined the relationship between individual variation in glucocorticoid plasticity in response to air temperature changes and reproductive success in a wild great tit population (Parus major). Over nine years, we collected repeated measurements of baseline and stress-induced corticosterone during nestling rearing. We found consistent reaction norm patterns in hormone response to temperature variation -- as shown in a previous study conducted over a shorter period. This provides robust evidence of individual differences in average hormone levels (intercepts) and the strength of the plastic response (slopes), indicating potential for evolution. However, neither intercepts nor slopes were associated with reproductive success (fledgling number or brood mass), suggesting that individual variation in endocrine plasticity was not under natural selection, at least within the environmental conditions experienced. This study provides a first empirical test of the evolutionary implications of endocrine plasticity in the wild and highlights the need to assess its fitness relevance under more extreme conditions, such as those expected under future climate scenarios.

Male-biased cooperative behaviours that produce public goods (male services) are widespread in primates. Recent behavioural studies suggest that male services may function beyond paternal investment, either as displays of competitive ability or as honest signals eliciting female choice. Because these hypotheses make contrasting predictions about the physiological state of service providers, endocrine measures offer a complementary approach for distinguishing between them. We investigated whether long-term testosterone and cortisol concentrations, measured from hair samples, were associated with four male services in wild vervet monkeys: alarm calling, participation in between-group conflicts (BGCs), leading river crossings, and sentinelling. Testosterone and cortisol concentrations increased with male competitive status, measured as a combination of dominance rank and recent rank trajectory, particularly during the mating period, establishing the endocrine profile associated with competition. In contrast, most male services showed few relationships with hormone concentrations: participation in BGCs was associated with lower cortisol concentrations and, to a lesser extent, lower testosterone concentrations. Because BGC participation is the strongest predictor of male mating frequency in this population, these findings indicate that males contributing to BGCs present an endocrine profile distinct from that associated with competitive state and instead support the prediction that high-quality males, irrespective of their dominance rank, can perform costly cooperative behaviours while maintaining relatively low physiological costs. More broadly, our results provide physiological support for reputation-based partner choice as a mechanism contributing to the maintenance of male services in primates.

Social relationships can buffer individuals against environmental challenges, reducing the physiological costs of disturbance. Assessing how social and environmental conditions jointly shape physiological stress is critical for predicting individual responses to disturbance, particularly in managed populations. We evaluated whether social and environmental stressors act additively or whether social context modifies physiological responses to environmental challenges. We combined behavioural data and faecal glucocorticoid metabolite samples from a small, intensively monitored population of African elephants (Loxodonta africana) in a fenced reserve. Using a Bayesian framework, we tested how social factors interacted with variation in the biophysical environment, including natural environmental and anthropogenic disturbances, to predict glucocorticoid concentrations. Natural environmental variables, including weather, water availability, and season, did not predict glucocorticoid concentrations. In contrast, helicopter use, a common management intervention, was associated with higher glucocorticoid concentrations. Social effects were context dependent. Following disturbance, low-ranking individuals showed higher glucocorticoid concentrations than high-ranking individuals, whereas this pattern reversed under low-disturbance conditions. Individuals with more social connections had lower glucocorticoid concentrations, but this effect was evident only under non-disturbance conditions. Measures of betweenness centrality did not predict glucocorticoid levels. These results demonstrate that social factors mediate physiological responses to anthropogenic disturbance and that management actions can impose uneven physiological costs across individuals. Quantifying interactions between social factors and the biophysical environment may improve conservation and management strategies for social species. Integrating physiological responses to interactions between social factors and the biophysical environment can guide conservation strategies and improve management interventions in social species.

Objectives: The bile acid nuclear receptor Farnesoid X Receptor (FXR, NR1H4) is a major regulator of metabolism and energy homeostasis in peripheral organs. It modulates bile acid, glucose, and lipid metabolism, as well as fat mass and body weight. However, FXR is also expressed in the brain, particularly in the hypothalamus, a key center for the regulation of energy homeostasis. Although one study has demonstrated a role for brain FXR activation in energy balance, its specific hypothalamic role is still unknown. Here, we examined the role of FXR in the mediobasal hypothalamus in the regulation of energy balance. Methods: We used a genetic approach combined with metabolic phenotyping to determine the effect of FXR invalidation in the mediobasal hypothalamus on metabolic parameters involved in the central regulation of energy homeostasis. Results: Our results demonstrate that hypothalamic FXR deficiency induces a positive energy balance, resulting in a reduction in energy expenditure due to alterations in glucose metabolism accompanied by structural changes in white adipose tissues. Conclusion: This study uncovers a previously unrecognized role for hypothalamic FXR in the central homeostatic control of energy balance, providing new insights into its contribution to peripheral glucose metabolism and adipose tissue structural remodeling.

Courtship is an essential component of reproductive success for many species and many courtship behaviors, such as vocalization, are energetically demanding. In order to successfully balance investment in courtship with feeding and foraging, individuals must be aware of their current energy balance, and hormonal signals of energetic state have been found to influence social signal effort across a variety of species. Ghrelin is one hormone that plays an important role in regulating energy balance by signaling hunger and promoting feeding. Previous studies have investigated the role of ghrelin in courtship, aggression, and mating behavior. In this study, we build on prior work by investigating the effects of ghrelin on ultrasonic vocalizations (USV) and other courtship behaviors of male mice. We expand on previous research by observing ghrelin's effects over longer interactions, allowing us to understand how ghrelin impacts the dynamics of USV production over time. Our results show that while males initially vocally court females at a high rate regardless of treatment, ghrelin reduces overall USV production by increasing the rate of decline of vocalization. Surprisingly, despite its effects on vocal courtship, we found no significant differences in the production or timing of other, non-vocal, courtship behaviors. This study deepens our understanding of the role of hormones traditionally associated with controlling hunger and feeding in regulating social behaviors.

Social animals must identify, evaluate, and appropriately respond to other individuals, often relying on multiple sources of information to guide context-dependent behavior. While individual recognition is thought to be widespread and critical for many social interactions (e.g. territoriality, dominance hierarchies), convincing demonstrations across animals beyond class-level recognition remain rare. Further, the cues animals use to recognize individuals remains poorly understood, especially in natural environments where they are exposed to numerous cues which may require cue integration. Here, we examine how socially dominant males of the African cichlid fish, Astatotilapia burtoni, use individual recognition to modulate aggression and whether this process depends on the spatial context. Using naturalistic experimental setups, we exposed males to familiar and unfamiliar neighbors while systematically manipulating spatial location and presenting a neighbor either singly or simultaneously to simulate competing social cues. Additionally, we measured circulating testosterone to assess endocrine correlates of recognition and aggression. We found that focal males habituated to familiar neighbors only when they remained in a consistent territorial location, demonstrating that spatial context is important for recognition. Further, when familiar and unfamiliar neighbors were presented simultaneously, males preferentially aggressed toward unfamiliar rival and adjust their aggressive response to the perceived threat of their neighbors, indicating that identity-based threat assessment is maintained under competing social demands. Together, our results show that recognition is a flexible, multi-faceted process that depends on the integration of identity and contextual information to guide territorial decision-making under dynamic social conditions.

Parasites decrease host fitness, more so during physiologically challenging life stages such as migration. However, parasites are unevenly distributed among individuals, and hosts with different physiological condition may face different costs of migration with infections. We tested whether the relationship between infection by haemosporidian parasites and oxidative balance during autumn migration in blackcaps depends on individual age and sex, two major sources of variation in prevalence and physiological condition. We captured blackcaps at stopover in central Spain and measured infection status and physiological parameters. Blackcaps physiologically more prepared to depart from stopover had lower antioxidant capacity of plasma, probably because of physiological adjustments prior to the upcoming flight stage. Plasmodium parasites occurred only in coinfections, which were more frequent among young blackcaps. Regardless of individual sex and age, coinfected birds had lower antioxidant capacity of plasma, and blackcaps coinfected with Plasmodium had more oxidative damage to lipids in their red blood cells. Our results support the idea that haemosporidian infections impair the oxidative balance of blackcaps during autumn migration, which could impair individual performance and ultimately fitness, with increased population impacts during the first year of life when a larger proportion of individuals migrate coinfected with harmful Plasmodium parasites.

Human and non-human animals often coordinate their behavior, a phenomenon thought to strengthen relationships by enabling sequential assessment of an interaction partners quality as a mate or rival, a process that directly affects evolutionary fitness. There is increasing evidence that behavioral coordination is reflected by synchronized neural activity of the on interacting partners, though few studies have examined synchronization at the level of gene expression. Here, we use Burtons Mouthbrooder cichlid, Astatotilapia burtoni, to examine how neural transcriptomes are synchronized while male-female pairs engaged in variable amounts of reproductive behavior. A. burtoni females naturally display highly coordinated reproductive behavior with a male partner only directly prior to spawning, yet this behavior can be experimentally induced with exogenous prostaglandin F2 alpha (PGF2a), which also acts by releasing pheromones to promote male courtship behavior. We quantified reproductive behavior and circulating sex steroid hormones of PGF2a-treated pairs. We then used transcriptome analysis of the preoptic area - a key node in the regulation of reproductive behavior across vertebrates - and identified gene co-expression modules that showed sex-specific activity in modulating reproductive behavior. Our results, which implement a novel approach to measure transcriptome synchronization, demonstrate a remarkable degree of male-female POA transcriptome synchronization that depends largely on the reproductive responsiveness of the female, mirroring how natural reproduction is driven by female behavior. Together, our work advances our understanding of the molecular mechanisms by which interacting individuals align their actions and how they experience social interaction.

Host-microbiota interactions are crucial in adapting to environmental changes, such as fluctuating energy availability. Yet, the extent to which hosts and their microbiota exhibit coordinated plasticity in response to transient energy limitation remains unclear. Here, we examined the capacity for parallel reversible plasticity in hosts and gut microbiota to temporary dietary restriction in hosts with differing energy needs. We subjected bank voles (Clethrionomys glareolus) from a long-term artificial selection experiment for high aerobic metabolism (A-lines) and control lines (C-lines) to dietary restriction (food dilution with insoluble fiber) followed by a recovery period. We measured traits relevant for vole energy consumption and fecal microbiota composition at baseline, after dietary restriction, and after recovery. We hypothesized that A-line voles would experience more severe and prolonged physiological effects of dietary restriction than C-line voles, which might be counteracted by higher microbiota responsiveness. Dietary restriction caused a temporary increase in food consumption, decrease in body mass and resting metabolic rate, and significant shifts in gut microbiota composition, all of which returned to near baseline levels during the recovery period. These effects were largely similar for the selection lines, but contrary to our prediction, the effect of dietary restriction on bacterial diversity was stronger in C-lines. This suggests higher resistance of the A-line microbiota to dietary changes, perhaps resulting from increased host control over microbial communities due to the directional selection for high metabolic capacity. Overall, our findings highlight a substantial capacity for reversible plasticity in host physiology and gut microbiota in fluctuating environments.

{beta}-arrestins 1 and 2 are intracellular adaptor proteins that regulate the subcellular localisation and signalling of GPCRs including Parathyroid Hormone Receptor 1 (PTH1R), which produces {beta}-arrestin-dependent signalling that may selectively stimulate bone anabolism. {beta}-arrestins can themselves be regulated by post-translational modifications including phosphorylation, which dictates the translocation and signalling of the few GPCRs studied in this context to date. We aimed to investigate whether phosphorylation of {beta}-arrestins modulates their subcellular translocation in response to PTH1R activation. Translocation of {beta}-arrestins to the plasma membrane and early endosomes was quantified using BRET biosensors and immunocytochemistry with high content analysis. Phosphoknockout or phosphomimetic mutations were introduced to previously demonstrated phosphorylation sites in {beta}-arrestins 1 and 2, initially in bulk to assess overall effects. Plasma membrane translocation was altered only subtly, whereas early endosome translocation was markedly reduced for both mutations but to a greater degree for the phosphomimetic. Contributions of individual or paired sites were assessed by restoration to wildtype from the bulk phosphomimetic mutants. Dual restoration of S13 and T275 in {beta}-arrestin 1, or the analogous sites in {beta}-arrestin 2, restored the greatest degrees of early endosomal translocation, with complete restoration for {beta}-arrestin 1 and partial for {beta}-arrestin 2. Restoration of other sites had minimal or no effect. Dephosphorylation therefore appears to be required for PTH1R-stimulated {beta}-arrestin early endosomal translocation, with different phosphorylation sites implicated than some other GPCRs. These findings raise the possibility of differential {beta}-arrestin regulation by distinct stimuli which may have implications in therapeutic targeting of {beta}-arrestin-dependent pathways.

Oxytocin (OT) and vasopressin (AVP) are neuropeptide hormones involved in regulating animal social behavior and a broad spectrum of physiological processes. Although their distributions are well documented in neuroendocrine regions of the forebrain and midbrain, their expression in the hindbrain remains poorly understood. Here, we used immunohistochemistry to quantify OT and AVP immunoreactive puncta within three auditory brainstem nuclei, the lateral superior olive (LSO), the medial superior olive (MSO), and the medial nucleus of the trapezoid body (MNTB) in six wild-caught rodent species differing in sociality. We also quantified the volume of these nuclei and examined variation in total brain volume across species and sociality. OT and AVP puncta count differed among species and social groups. Group-living species exhibited higher OT and AVP puncta counts than monogamous and solitary species in the LSO and MNTB. In the MSO, OT puncta counts did not differ among social groups, whereas AVP puncta counts were higher in group-living than in monogamous and solitary species. Total brain volume and the volumes of the MNTB and MSO differed among species, but not across social groups, whereas LSO volume did not differ among species or sociality. These findings revealed sociality-related variation in OT and AVP immunoreactive puncta within auditory brainstem circuits and suggest that neuropeptide signaling within early auditory brainstem pathways may contribute to the neural integration of social and auditory information.

Stressful events are associated with long-term adverse health impacts, but the causal mechanisms linking these exposures to subsequent disease remain poorly understood. One plausible mechanism is persistent changes to hormonal signaling that regulate metabolic homeostasis. Here, we examine the long-term impacts of stress associated with exposure to the 2004 Indian Ocean tsunami on levels of free triiodothyronine (FT3), a circulating measure of biologically active thyroid hormone, using data from the Study of Tsunami Aftermath and Recovery. We measure biomarkers 20 years after the tsunami in a population-representative sample age 35y+ in 2024 who, at the time of the tsunami, were living along the coast of Aceh, Indonesia, the most affected part of the Indian Ocean Basin. Because respondents were first interviewed before the tsunami and subsequently tracked regardless of migration, the sample avoids a major source of selection bias common in long-term disaster studies. We identify the causal effect of tsunami exposure using variation in community-level tsunami mortality, comparing communities within the same sub-district. We find that greater tsunami exposure reduced levels of FT3 20 years later. Exposure also altered relationships between FT3, body composition, and cortisol and increased cardiometabolic risk. These findings identify persistent alteration of thyroid hormone physiology as a potential pathway linking severe stressful exposures to long-term cardiometabolic disease risk.

Menopause is a major neuroendocrine transition characterised by substantial changes in endocrine milieu, physiological, psychological, and psychosexual health. Although menopausal symptoms are common, their range and severity vary considerably between individuals, suggesting that menopause is a multifaceted process. Endocrine markers (luteinising, follicle-stimulating & anti-Mullerian hormone), together with perceived well-being, may contribute to this variability. Thus, the aim was to capture the complex impact of endocrine and well-being markers on psychosexual health and menopausal symptoms. Therefore, we first applied principal component analyses to identify individual endocrine and well-being profiles, to then assess their association with psychosexual health and menopausal symptoms in pre- and post-menopausal females. Post- compared to pre-menopausal females report reduced psychosexual health and greater urogenital and psychological menopausal symptom burden. Endocrine and well-being profiles interact with reproductive status: Post-menopausal females with lower subjective well-being and a stronger menopause-like endocrine milieu report decreased overall psychosexual health and more sexual related pain. Additionally, endocrine milieu interacted with reproductive status on urogenital symptoms: Post-menopausal females with a stronger menopause-like endocrine milieu report less urogenital symptoms. Together, these findings suggest that endocrine factors and subjective well-being jointly influence psychosexual health and menopausal symptoms after menopause. No association is seen before menopause. Therefore, females after menopause need to be considered separately in research and clinic. Multivariate analyses capture patterns that are not identified using individual biomarkers and conventional univariate approaches. Our findings highlight the value of integrative multivariate approaches for improving the assessment of menopausal health and characterising individual variability across the menopausal transition.

Reliable morphological criteria for sexing birds without the need for invasive procedures are scientifically and ethically valuable. Smith et al (2005) reported that iris colour assigns the genetic sex of Starlings Sturnus vulgaris with 98% accuracy, and bill base colour with 100% accuracy when birds are in breeding condition, but these figures have not been tested independently. We applied their criteria to 31 captive Starlings in breeding condition, using three observers blind to genetic sex, two of them new to Starling sexing. Bill base colour correctly predicted genetic sex for all 29 birds scored, with complete observer agreement. Mean iris score was correct for 27 of 31 (87.1%), fewer than the 94 of 96 reported by Smith et al (2005) for birds in breeding condition (Fisher exact test, P = 0.031), although with so few errors in either study this comparison is imprecise. Observer agreement was high, so these errors reflect iris colouration conflicting with genetic sex rather than inconsistent scoring; bill base colour was correct for all four misassigned birds. Body mass and tarsus length classified 77% and 58% of birds correctly, their published thresholds missing in opposite directions. We conclude that bill base colour should be the primary criterion for sexing Starlings in breeding condition; the accuracy of iris colour should not be assumed to be 98%.

Ethanol occurs naturally in sugar-rich foods used by insects, but its effects in bees have been studied primarily in honeybees. We tested whether dietary ethanol affects survival and locomotor performance in workers of the bumblebee Bombus terrestris (L.). In the survival experiment, workers were fed ethanol (0, 1, or 10%) for 21 days; in the locomotor experiment, they were fed the same doses for one or seven days, after which we measured spontaneous movement using an open-field assay. We measured the proportion of time in movement, speed of movement, path meander (curviness), and arena exploration. The 10% ethanol concentration greatly increased the risk of mortality, whereas the estimated effect of 1% ethanol was smaller and statistically inconclusive. In terms of locomotion, the largest differences occurred after seven days of exposure to 10% ethanol. Workers in this treatment showed greater path meander and lower exploration than control workers. Speed was also lowest in this group. Evidence that exposure for seven days was worse than for one day at the same concentration was detected only for exploration. No clear locomotor effect was detected at 1% ethanol exposure. These findings provide comparative data on sustained ethanol exposure in bumblebees and show a strong concentration-dependent contrast, with substantial effects under high-concentration challenge but no clear effects on the measured endpoints at 1%.

The consequences of maternal effects for offspring fitness can depend on the environmental conditions offspring encounter and the fitness traits considered. We used a transgenerational experiment in Daphnia magna to test how maternal exposure to warming and elevated salinity influenced offspring survival, reproduction and body size across matching, mismatching and multiple-stressor environments. Maternal exposure to salinity enhanced offspring survival under matching salinity, and benefits extended to mismatching environments. In contrast, maternal exposure to warming provided no survival benefit under matching warming and reduced survival in mismatching environments, while accelerating reproduction across contexts. Multiple-stressor conditions revealed pronounced maternal effects, while contrasting responses across survival, reproduction and body size showed that benefits to one fitness trait did not extend to others. Our findings demonstrate that environmental matching alone is insufficient to predict maternal effects, whose consequences depend on offspring environmental complexity and the fitness trait considered.

Pesticide use is ubiquitous. While pesticide resistance in target species such as insects is a well-known phenomenon, it is less known how pesticide exposures affect the genetics of non-target species. Here, we demonstrate the research value of integrating existing datasets to study the relationship between chemicals and biodiversity from the genetics perspective by analyzing spatial pesticide concentration data and genetic data from Europe that were not initially generated for toxicological purposes. Specifically, we found associations between environmental pesticide concentrations and genetic variation (i.e., single nucleotide polymorphisms, SNPs) in a non-target species, the wild boar. Gene Ontology (GO) terms and biological signaling pathways related to nervous system function were overrepresented for the impacted genes, especially for insecticides and fungicides. Further, we found that external studies characterizing the molecular mechanisms of these pesticides revealed the same pesticide - GO relationships as those observed in our analysis. Our results show that pesticide-induced genetic changes may not be constrained to target species but may also have an impact on the long-term viability of other wildlife populations. We therefore encourage further research into this area and collaboration across disciplines to develop more comprehensive designated datasets for such analyses. This finding also urges the consideration and inclusion of chemical exposure into conservation protection strategies and greater consideration of genetic impacts from chemicals in environmental risk assessment.