Neville Pillay

Urban wildlife must persist in close proximity to humans. A reduced flight initiation distance (FID) is a widely reported behavioural correlate of this exposure. FID is lower in rock hyraxes ( Procavia capensis ) near permanent human settlements than in undisturbed populations in a national park landscape, but whether similar variation exists at finer spatial scales within a single suburban site has not been tested. We measured FID in three hyrax colonies differing in distance from human dwellings at Meyersdal Eco Estate, Johannesburg, South Africa, with and without food present, in the warm and cool months. Inter‐colony distances (1.8–2.1 km) exceeded the typical hyrax home‐range size and reported dispersal distances, supporting the treatment of the colonies as independent sampling units. Colony and food treatment each accounted for a similar proportion of variance in FID ( η ² = 0.148 and 0.150 respectively), with no evidence that the effect of food differed among colonies. The colony furthest from human dwellings had longer FID than the two closer colonies, which did not differ from each other, indicating a threshold rather than a continuous relationship with distance. The presence of food reduced FID consistently across colonies, but season had no effect. These patterns are consistent with reduced escape responses at closer proximity to humans and with feeding motivation acting as an independent, similarly weighted influence on escape decisions. However, the single colony per distance design means that the colony effect cannot be separated from other between‐colony differences. The results indicate to a multi‐factor view of urban antipredator behaviour in which exposure to people and immediate behavioural context both influence flight initiation decisions.

Pyracantha koidzumii (Hayata) Rehder is native to Taiwan, where it has an endangered IUCN conservation status, although it is invasive in other parts of the world. It was introduced to South Africa as an ornamental species. In South Africa, P. koidzumii is classified as having density-based negative impacts, although its distribution is sparse and no impact assessments have been conducted to date, compared with its established congener, Pyracantha angustifolia. We asked the following questions: (1) does the current distribution of P. koidzumii and P. angustifolia indicate any relationship with anthropogenic activities as the main driver of plant invasions; (2) what are the seed viability and germination capacity of P. koidzumii?; and (3) what is the current distribution and habitat suitability of P. koidzumii relative to P. angustifolia, and does P. koidzumii show any potential to be invasive in different climate change scenarios (i.e., SSP1 and SSP5). We found a significant relationship between land use and cover and species occurrence records, with disturbed areas having the highest occurrence records (43.5%; N = 4297), followed by grassland (23.4%). The seed viability and germination capacity were high (78.6–87.2%; n = 50), confirming that P. koidzumii can successfully recruit in southern Africa. Climate suitability projections across scenarios for both species yielded a strong data fit (i.e., training AUCs above 0.9), with precipitation as the most important climate predictor. The climate-based habitat suitability projections showed greater net expansion for both species in SSP1, with P. angustifolia projected to invade 254,974 km², while P. koidzumii could invade 49,829 km². Alternatively, there was contraction (i.e., positive net habitat loss) of suitable habitat in SSP5, characterised by significant area loss for P. angustifolia (12,0139 km²), while P. koidzumii displayed a moderate loss (13,174 km²). For the first time, this study showed that P. koidzumii has high potential to invade the southern African grassland biome, driven by high germination combined with biophysical disturbance, and that its future habitat occupancy will be moderately affected by extreme environmental temperature conditions.

Olfactory enrichment is recommended for captive felids, but systematic evidence on practical implementation in multiple species and institutions is limited. We evaluated a simple, keeper-safe scent diffuser delivering spice-based odours to captive lions (Panthera leo), tigers (Panthera tigris), jaguars (Panthera onca), leopards (Panthera pardus), cheetahs (Acinonyx jubatus) and pumas (Puma concolor) at two zoological institutions in Johannesburg, South Africa. Behaviour was recorded during baseline and scent-exposure conditions in 23 individuals. Behavioural diversity (number of distinct behaviours per 15-min session) was the primary outcome. Engagement duration, latency to approach and individual response consistency were also quantified. Animals were exposed to a compound spice blend and four component spices (coriander, paprika, black pepper and garlic) and subsequently to decreasing concentrations of their most preferred scent. Behavioural diversity increased significantly during scent exposure at both institutions (1.9 times greater at Lory Park and 1.8 times greater at Johannesburg Zoo), with large effect sizes at both sites (Cohen’s d ≥ 1.2). Spice type did not significantly affect behavioural diversity, but individual animals showed consistent engagement preferences, approach latencies and response profiles during repeated exposures. Full odour concentrations showed significantly longer engagement durations than low concentrations at both institutions (approximately twofold at Lory Park and threefold at Johannesburg Zoo), but behavioural diversity did not differ significantly between concentration levels. No significant species differences were detected, indicating that assessment by individuals is more informative than species level predictions for enrichment planning. Spice-based diffusers provide a practical, low-cost enrichment tool suitable for multi-institutional implementation. Moreover, enrichment programmes should be evaluated and tailored at the individual animal level.

Early‐life environments can shape behavioural development trajectories without altering DNA. In this review, we consider how non‐genetic factors, particularly parental care, shape behavioural development in rodents, using African striped mice ( Rhabdomys ) as our primary model. The Rhabdomys system is particularly informative because it encompasses a natural gradient from solitary to group‐living strategies, demonstrates marked social plasticity and combines field observations with laboratory experimental manipulations. Long‐term studies of Rhabdomys , integrated with broader rodent research including laboratory rats, mice and voles, reveal that early parental care creates lasting changes in sociality, stress physiology, cognition and reproductive behaviour. These changes are mediated through epigenetic, hormonal and neuroendocrine mechanisms that can persist across generations. We frame this review within Developmental Systems Theory (DST), which considers development as the emergent dynamic interplay of genes, environment and experience. Maternal care, via tactile stimulation, diet and social context, forms the primary basis of early caregiving, while paternal and communal care contribute significantly to development in biparental and group‐living species. Cross‐fostering and isolation experiments demonstrate that caregiving can modify developmental trajectories independent of genetic inheritance. This plasticity enables behavioural adjustments to local ecological conditions; when outcomes are adaptive and transgenerationally stable, caregiving itself becomes a target of selection. Understanding developmental plasticity as an evolutionary force, rather than noise around a genetic mean, improves our ability to predict behavioural trajectories under environmental change. This framework has direct applications in conservation biology, captive breeding programmes and perinatal medicine. Because these developmental mechanisms are conserved across vertebrates, rodent studies provide broad insights into how plasticity in caregiving contributes to rapid behavioural evolution.

This study quantifies spatial patterns and socio-economic drivers of wildlife-related losses at the agricultural–conservation interface in north-eastern South Africa. Using structured interviews with 249 farmers across five localities (Limpopo, Mpumalanga, KwaZulu-Natal), 173 respondents reported wildlife incursions. Crop damage was dominated by primates vervet monkeys and chacma baboons while leopards were the principal game/livestock predator. Subsistence households bore the heaviest burden: they accounted for most crop-raiding reports. They faced heightened food-security risks, whereas commercial operations suffered larger monetary losses but had greater capacity to deploy deterrents. Irrigation was associated with increased conflict incidence, and electrified fencing reduced losses for some subsistence farms but was not uniformly effective in high-risk localities. Larger household size correlated with greater exposure to incursions than small households. We recommend targeted, locality-specific, multi-species mitigation: prioritise support and maintenance for effective deterrents in vulnerable communal areas, integrate community engagement and monitoring, and align conservation policy with livelihood resilience to reduce inequitable impacts.

Phenotypic responses to climate affect individual fitness, but the extent to which this translates into effects on population dynamics remains poorly understood. We assemble 213 time series on phenotypes and population sizes of wild vertebrates globally and match them with local climate data. Our meta-analysis shows that morphological traits are mostly climate insensitive. However, phenology is earlier in warmer-than-average years, which contributes positively to population growth in most species. At lower latitudes, temperature has weaker effects on phenology but stronger direct negative effects on population growth, likely because these populations are less capable of tracking climate via plasticity. Variation in the phenology-mediated effect of temperature on population growth cannot be explained by latitude, generation time, migratory mode, or diet. This suggests that simple relationships between species characteristics and population responses to warming may not occur in nature. Instead, we may need to embrace ecological complexity by considering local-scale predictors that capture intra-specific variation.

Spatial and social population structures can influence intra- and interspecific genetic processes. We investigated the spatial and social genetic structure of two sister species and evaluated whether there was evidence of hybridisation between them at a microgeographic scale, in syntopy. Our study models were Rhabdomys bechuanae (Rbech) and Rhabdomys dilectus dilectus (Rdil). We generated population genetic data using microsatellite markers and cross-referenced some of these results with published behavioural data from a prior study, reanalysed here. We compared genetic diversity and gene flow both in sympatry and allopatry, we tested for hybridisation between the sister species in sympatry and assessed the relationship between kinship and fine-scale spatial and social organisation. Genetic diversity was high within all populations of the two species. Population genetic substructure was more pronounced in Rbech than in Rdil, consistent with stronger group cohesion reported for Rbech. STRUCTURE and NEWHYBRIDS analyses suggested that sympatric individuals, 5% in Rbech, and 2% in Rdil, might have hybrid ancestry. Our results indicate social fences may limit gene flow within and between species. Further, limited hybridisation suggests that, despite syntopy, only rare events of hybridisation may occur, possibly at phases of density troughs and/or that F1 hybrids have a relatively low fitness.

Animals are adapted to cope with harsh environments. Understanding these adaptations is crucial to assessing species resilience to global change. Harsh environments are characterised by persistent and long‐lasting factors that threaten homeostasis and survival, such as reduced food and water availability, seasonal cold or heat. We review two decades of field studies exploring how African striped mice ( Rhabdomys pumilio ) are adapted to harshness in the Succulent Karoo semi‐desert, which is characterised by hot, dry and food‐restricted summers and moist, benign winters. Striped mice adapted to harshness via multiple behavioural and physiological mechanisms, which reduce energy consumption and increase water retention. These mechanisms include social flexibility, communal huddling, sun‐basking, reducing activity, a broad range of blood glucose regulation, decreased levels of metabolic hormones and decreased resting metabolic rate. Together, these mechanisms lead to an overall reduction of daily energy expenditure during harsh summers. This harshness response contrasts with the physiological stress response, which is characterised by increased energy expenditure to overcome the stress via the secretion of catecholamines and glucocorticoids. In contrast, the harshness response is characterised by reduced levels of glucocorticoids and allows endurance of the harsh conditions. We conclude that the harshness response is fundamentally different from the stress response.

Animals in arid environments must maintain water balance despite persistent drought, heat and low food availability. Blood serum osmolality offers an integrative physiological measure of hydration, yet no prior study has examined it in wild mammals across multiple seasons and years. Using 12 years of field data from African striped mice (Rhabdomys pumilio) inhabiting the Succulent Karoo semi-desert, we investigated seasonal variation in serum osmolality. This region features cold, moist winters with high food availability and hot, dry summers with scarce resources. Season, maximum temperature and food availability were collinear and tested independently – each was statistically significant. Serum osmolality was higher during the dry season, particularly when food availability was low. While temperature best predicted osmolality across seasons, food availability explained more variation within the dry season. Our findings establish serum osmolality as an indicator of environmental harshness in xeric mammals.