Research Articles (Zoology and Entomology)
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Item Keeping up with the times : the application of innovative techniques in forensic entomologyKotze, Zanthe; Martin-Vega, Daniel (Wiley, 2025-03)Advancements in technology have meant that there have been significant developments in the field of forensic entomology, allow researchers to develop tools to more accurately identify entomological evidence, as well as provide more accurate estimates of postmortem interval (PMI).Item Low genetic diversity and regional isolation of South Africa’s inshore Bryde’s whalesPaynee, Dominique Kelsi; Vermeulen, Els; Penry, Gwenith S.; Elwen, Simon; Matthee, Conrad; Andreotti, Sara; Bloomer, Paulette (Springer, 2026-02-03)Effective conservation of cryptic marine species depends on a sound understanding of genetic diversity, population structure and connectivity. These data allow for the delineation of conservation units and assessment of extinction risk and are especially valuable for species with fragmented distributions or suspected regional endemism. The Bryde’s whale (Balaenoptera edeni) exemplifies a challenge, being a poorly understood baleen whale species globally, with a complex of resident inshore and migratory offshore populations across temperate and sub-tropical waters. One such is the inshore population that inhabits South African coastal waters, where it is classified nationally as Vulnerable (D1) due to its small population size. This study uses a panel of 14 microsatellite markers and mitochondrial DNA control region sequences to advance our understanding of the genetic isolation and extinction risk of this population, informing the delineation of conservation units and guiding population-specific management actions. Results indicate that this population is characterized by moderate nuclear microsatellite and low mitochondrial DNA diversity and preliminarily indicate genetic differentiation between populations in the southern African region. On a global scale the findings show differentiation between broad ocean regions and the SAi while supporting the difference in evolutionary origin of SAi and SEA. These findings underscore the need for active conservation management for this isolated coastal population since they provide genetic evidence for the recognition of a discrete management unit. It is recommended that further refinement in understanding of the population’s evolutionary distinctiveness will strengthen conservation assessments, support listing decisions, and guide targeted management interventions.Item Unlocking opportunities for meaningful participation of land reform beneficiaries in the wildlife economyShwababa, Siviwe; Child, Matthew F.; De Vos, Alta; Mneno, Naledi; Clements, Hayley S. (Elsevier, 2025-07)Land reform is a key social justice movement across the world, typically focused on agricultural land uses. However, in many parts of the world, land reform properties exist in regions that have high biodiversity value, where options exist for integrating land reform with wildlife-based land uses to promote both conservation and socio-economic development. To effectively design and implement policies aimed at unlocking this under-explored pathway towards inclusive wildlife economies, we need information on the opportunities and barriers confronting the establishment and operation of viable wildlife enterprises on redistributed land. We conducted a survey of 19 landholders awarded land through reform in the Eastern Cape Province of South Africa. We aimed to understand the state of wildlife economy development and assess investment needs for these market entrants. Their characteristics were contrasted with data on 74 established wildlife ranches and 21 conventional livestock farms. Despite all land reform properties listing wildlife-based economic activities in their business plans and most (84 %) having wildlife, only 42 % were generating (very limited) income from their wildlife. Common barriers to upscaling revenues from wildlife were a lack of infrastructure (particularly fencing, water, accommodation) and wildlife stocks. Engagement in the wildlife economy is further hindered by lack of decision-support on viable wildlife business models and subsequent lack of access to skills development and market information. Our results show mismatches between activities that are supported by government and property business plans, and those that are context-appropriate and viable. We suggest that South Africa’s land reform programmes need to develop targeted infrastructure and skills development that consider the most appropriate business model for a given site. The barriers and opportunities outlined here could inform strategies that leverage state and private investment to more effectively create viable wildlife-based business models and achieve the dual goals of social justice and biodiversity conservation in South Africa.Item Extraction of saliva, haemolymph, salivary glands, and midgut from individual ticks (Acari: Ixodidae)Khogali, Rua Khogali Ibrahim; Getange, Dennis; Bastos, Armanda D.S.; Masiga, Daniel; Villinger, Jandouwe (MyJove Corporation, 2025-10-31)Ticks are blood-feeding ectoparasites recognised for their ability to transmit several infectious pathogens to humans and animals. Tick-borne pathogen (TBP) surveillance generally relies on detecting pathogens in homogenates of entire ticks, including those acquired during blood feeding, which may not be transmitted by the tick. To better understand the pathogen transmission mechanism, it is essential to investigate the dissemination and concentration of TBPs in various tick tissues, which is important for elucidating transmission mechanisms in ticks and determining their vector competence. This, in turn, rests on procedures for isolating saliva, haemolymph, salivary glands, and the midgut of individual ticks in order to examine the location of TBPs within these tissues and fluids. In this study, we describe a protocol for tick tissue collection, including a novel procedure for the collection of haemolymph. The results confirm that Rickettsia africae occurs at higher levels in the haemolymph of Amblyomma gemma, affirming the likely role of this tick species as a competent vector for R. africae. In contrast, Hyalomma dromedarii exhibited high rates of R. africae in the midgut, but the bacterium was absent in the haemolymph. The presence of TBPs in the haemolymph is therefore a valuable indicator of vector competence, and rests on the availability of a method that ensures ease of collection.Item Systematics of African rough-scaled lizards, with description of two new species from eastern Angola (Squamata: Lacertidae: Ichnotropis Peters, 1854)Conradie, Werner; Keates, Chad; Greenbaum, Eli; Lobon-Rovira, Javier; Tolley, Krystal A.; Benito, Max; Pinto, Pedro Vaz; Van Breda, Reuben V.; Verburgt, Luke (Pensoft Publishers, 2025-11)Ichnotropis is a genus of medium-sized lacertids endemic to sub-Saharan Africa, characterised by rough head shields. The genus currently comprises six nominal species distributed across much of southern, central, and eastern Africa. Some species are apparently active at only certain times of the year, resulting in limited specimen collections and severely hampering research. This scarcity of material has historically made comprehensive systematic reviews of the genus difficult and has led to the description of numerous regional morphological variants as distinct species or subspecies. Material collected in recent years has enabled us to provide a new phylogenetic hypothesis of Ichnotropis using two mitochondrial genes (16S and ND4) and two nuclear genes (c-mos and RAG-1). Our phylogenetic dataset includes 56 individuals representing five of the six currently recognised species (excluding I. chapini). Additionally, the broad geographical sampling of the widespread I. capensis group has allowed us to explore the taxonomic status of several species and subspecies within the group. As a result, we demonstrate the monophyly of Ichnotropis in relation to other African lacertids and present the most comprehensive phylogeny of the genus to date. We also provide the first phylogenetic placements for I. tanganicana and I. grandiceps, which allows us to validate their taxonomic statuses. Furthermore, we recovered a new cryptic species closely related to I. grandiceps, and identified several well-supported clades within the I. capensis group, all corroborated by multi-locus species delimitation analyses. One of these clades is described herein as a new species, while the remaining taxa of interest are discussed and highlighted for future investigation. Based on our findings, we recommend the following taxonomic revisions: Ichnotropis longipes and I. macrolepidota should remain synonyms of I. capensis; I. bivittata pallida and I. capensis nigrescens are treated as a junior synonyms of I. bivittata; and I. overlaeti is considered a junior synonym of I. tanganicana. Although we could not determine the phylogenetic placement of I. chapini due to the lack of genetic material, its head morphology and scalation support its reassignment to the I. bivittata group. Thus, it is retained as a valid species pending the availability of new material for further taxonomic actions. In conclusion, this study resolves several long-standing taxonomic issues within one of Africa’s most understudied lacertid genera and lays a solid foundation for future research on the genus Ichnotropis.Item Multi-locus sequence analysis of Anaplasma in the common warthog (Phacochoerus africanus) from South AfricaRea, Keaton; Buss, Peter Erik; Bastos, Armanda D.S. (Elsevier, 2025-12)The prevalence and diversity of Anaplasma in common warthog (Phacochoerus africanus) was investigated using a multi-locus sequence analysis (MLSA) approach targeting the 16S rRNA, citrate synthase (gltA) and heat-shock operon (groESL) genes. PCR screening of 100 warthog samples from the Kruger National Park in South Africa with eight published assays identified 50 positive animals, all of which were initially identified with the 16S rRNA assay. In contrast, the gltA and six groESL assays recovered PCR-positivity rates of 2 % and 0 %-4 %, respectively. As optimisation did not improve Anaplasma detection rates, an alternative groESL assay targeting a 923 bp region was designed. This new assay detected 45 positive animals, all of which were positive with the 16S rRNA assay. Nucleotide sequencing of the three MLSA gene targets confirmed that 50 % (50/100) of warthogs were Anaplasma-positive. Juvenile warthogs displayed a significantly higher infection rate (15/18; 83.3 %) than adults (35/82; 42,68 %). Phylogenetic analyses of individual and concatenated gene datasets confirmed that the Anaplasma species in warthogs is closely related to the species detected in Ornithodoros soft ticks from Zambia. This, together with the high levels of nucleotide sequence identity (≥98.97 %), suggests the likely existence of a host-restricted cycle involving warthogs and the soft ticks that inhabit their burrows. Based on the distinctiveness and monophyly of the Anaplasma species in warthogs and Ornithodoros soft ticks, confirmed through genetic characterisation of three gene regions, we propose that Candidatus status be assigned and suggest “Candidatus Anaplasma ornithodorii”. HIGHLIGHTS • Overall sequence-confirmed Anaplasma prevalence of 50 % in warthogs. • Three gene regions (16S rRNA, gltA and groEL) were characterised. • Anaplasma species in warthogs matches species detected in Ornithodoros soft ticks.Item Reproductive females of a cooperatively breeding rodent are in better body condition when living in large groupsFinn, K.T.; Janse van Vuuren, Andries Koch; Suess, Tobias; Hart, Daniel William; Bennett, Nigel Charles; Zottl, M. (Wiley, 2025-07)Cooperation and group living have been suggested to facilitate survival in varying environments and under challenging conditions. However, group living may also be associated with costs, particularly in species where individuals within groups may compete for limited resources. The costs and benefits of cooperative group living on cooperatively breeding mammals in varying environments remain unclear. Here, we use data collected from wild, cooperatively breeding Natal mole-rats (Cryptomys hottentotus natalensis) inhabiting a seasonally varying environment to assess whether body condition changes between seasons and whether these changes are contingent upon group size. We demonstrate that the body condition of reproductive females improved with increasing helper number during both the benign summer and the harsher winter seasons. However, the body condition of other group members showed little dependency on group size or season. Only when including one extremely large group did the body condition of non-breeders weakly, albeit significantly, change depending on group size and seasonality. These results suggest that larger group sizes may yield some benefits for non-breeding group members during winter and may invoke some costs during summer. Group living in Natal mole-rats is likely promoted by a combination of collective foraging, thermoregulatory benefits, and potentially some indirect fitness benefits through improved body condition of the breeding female.Item Fertility up in flames : reduced fertility indices as a consequence of a simulated heatwave on small African mammalsJacobs, Paul Juan; Bennett, Nigel Charles; Du Plessis, L.; Hart, Daniel William (Wiley, 2025-03)With the increasing frequency and intensity of heatwaves due to climate change, the survival and reproductive success of mammals could be under significant threat. However, the specific effects of these environmental stressors on mammalian reproductive fitness remain insufficiently explored. This study investigates the impact of a simulated heatwave on male fertility indices in two African rodent species: the mesic four-striped field mouse (Rhabdomys dilectus) and the Namaqua rock mouse (Micaelamys namaquensis) during the breeding season. We measured key indicators of male fertility, including testes mass, testes volume, seminiferous tubule diameter, the presence of sperm, and plasma testosterone levels. Our findings reveal that both species experienced significant effects on male fertility indices, with the smaller R. dilectus showing a decline in all fertility indices following a simulated heatwave. These results suggest that the projected increase in heatwave events may compromise the reproductive success of small mammals, potentially leading to population declines. Finally, this study highlights the need for focused studies on the effect of heatwaves on long-term reproductive success in both males and females.Item Examining alterations in fGCM concentrations post-defaecation across three animal feeding classes (ruminants, hindgut fermenters and carnivores)Osburn, Kayla Rae; Crossey, Bruce Gareth; Majelantle, Tshepiso Lesedi; Ganswindt, Andre (Wiley, 2025-05)Quantification of faecal glucocorticoid metabolites (fGCMs) is a popular non-invasive technique for monitoring wildlife's response to stressors, demanding an understanding of the stability of fGCM concentrations post-defaecation to ensure comparability of determined fGCM values across samples. To provide species-specific recommendations for the duration within which sampling can take place, we measured the rate at which the fGCM concentrations of nine different species changed throughout a 7-day period post-defaecation. In this study, we explored the temporal dynamics of fGCM concentrations in nine species across three feeding classes (ruminants, hindgut fermenters and carnivores): impala (Aepyceros melampus), giraffe (Giraffa camelopardalis), blue wildebeest (Connochaetes taurinus), plains zebra (Equus quagga), African elephant (Loxodonta africana), white rhino (Ceratotherium simum), cheetah (Acinonyx jubatus), spotted hyena (Crocuta crocuta) and leopard (Panthera pardus). Utilizing enzyme immunoassays already established for each of the focal species, we identified broader feeding class-specific patterns. All herbivores exhibited a significant decrease in fGCM concentrations over time, starting from 6 h (impala) to 48 h (giraffe, blue wildebeest, white rhino and African elephant) post-defaecation. For carnivores, concentrations remained fairly comparable for 12–24 h, after which fGCM concentrations either decreased (spotted hyena), increased (leopard) or remained stable (cheetah), with notable variation in triplicate concentrations (cheetah and leopard). These findings offer insights into scheduling faecal sampling for endocrine monitoring, particularly from free-roaming wildlife, to ensure comparability of determined hormone metabolite concentrations. Furthermore, the species-specific variation in fGCM concentration post-defaecation demonstrated in this study underlines the necessity to investigate every new species to ensure accurate and comparable results. Future studies ought to investigate how the mass of collected material, sex and drying methodologies affect the measurement of fGCMs post-defaecation.Item Endemic plants and animals are susceptible to extinction in an imperilled alpine hotspot in southern AfricaTaylor, Peter J.; Bredenhand, Emile; Monadjem, Ara; Armstrong, Adrian J.; Rakotoarivelo, Andrinajoro R.; Mdluli, Veli Monday; Howard, Alexandra; Modise, Serero; Motitsoe, Samuel N.; Ntloko, Pindiwe; Kirkaldy, Abigail P.; Kleynhans, Dewald J.; Jankielsohn, Astrid; Mosikidi, Toka; Oosthuizen, Maria Kathleen; Payne, Stephanie; Munyai, Thinandavha C.; Carbutt, Clinton; Ramoejane, Mpho; Bereng, Mosiuoa; Stiller, Michael; Haddad, Charles R.; Steenhuisen, Sandy-Lynn; Mlambo, Musa C.; Moyo, Sibusisiwe; Nyembe, Nthatisi I.; Mofokeng, Lehlohonolo; Van As, Johann; Malekana, Lesego; Daniel, Gimo M.; Gwate, Onalenna; Van As, Michelle; Harrison, James Du Guesclin; Thabethe, Nokubonga F.; Kheswa, Nozipho; Moloi, Karabo; Sishange, Nkanyiso; Clark, V. Ralph (South African National Biodiversity Institute, 2025-11)BACKGROUND : As global temperatures rise, alpine species at the upper limit of their distribution are at risk of decline and extinction due to shrinking habitats downslope. The alpine (> 2 800 m a.s.l.) biodiversity of the Maloti-Drakensberg is poorly known but may be threatened by climate change. OBJECTIVES : Using expert BioBlitzes, we documented species richness and elevational patterns of distribution in 14 plant and animal higher taxa from alpine and upper-montane zones in an unexplored corner of the Maloti-Drakensberg. METHODS : Using standardised methods such as Sherman traps, acoustic monitoring, bird timed counts, pitfall traps, sweep nets, aquatic SASS5 kick-nets, timed searches and herbarium collections, we assessed elevational zonation of flowering plant and selected invertebrate and vertebrate diversity in the Witsieshoek Community Conservation Area (WCCA). RESULTS : GBIF records complemented expert BioBlitz data, together enumerating 1 216 plant, vertebrate and invertebrate species along an elevation gradient from 1 760 m to 3 145 m at WCCA. Birds, insects and plants showed concordant beta diversity patterns from BioBlitz and GBIF data: high turnover compared to nestedness in more sedentary insects and plants, and the opposite in more mobile birds (GBIF data not available for bats). Although identifications are ongoing, 17% of species or morphospecies were exclusively recorded in the alpine zone, including 82 species of plants and 92 of animals. CONCLUSION : Alpine endemics are vulnerable to the ‘escalator to extinction’ process due to climate change. Surveys of under-explored alpine hotspots should be prioritised, drawing on mountain tourism-based citizen science. We advocate an ecotourism- and community-centred, restoration and rewilding approach for this strategic and biodiverse community conservation area.Item A South African perspective on the 2023 IPBES Thematic Assessment Report on Invasive Alien Species and their controlWilson, John R.U.; Faulkner, Katelyn T.; Winzer, L. Fernandez; Mcculloch-Jones, E.J.; Van Wilgen, B.W.; Blanchard, R.; Carbutt, C.; Dechoum, M.S.; Foxfroft, L.C.; Greve, Michelle; Hui, C.; Ivey, P.; Kgope, B.; Kumschick, S.; Le Roux, Peter Christiaan; Masehela, T.S.; Measey, J.; Miza, S.; Mogapi, T.; Mpikanisi, F.; Mulaudzi, L.; Nelukalo, K.; Nnzeru, L.; Nsikani, M.M.; Pattison, Z.; Rahlao, S.J.; Richardson, D.M.; Robinson, T.B.; Shackleton, R.T.; Tererai, F.; Tshidada, N.; Tshikhudo, P.P.; Tshivhandekano, I.; Wanjau, K.; Ziller, S.R.; Zengeya, Tsungai Alfred (South African National Biodiversity Institute, 2025-11-06)BACKGROUND : Biological invasions are a major threat to biodiversity and sustainable development. A global assessment of biological invasions released in 2023 by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), concluded that while invasions ‘…cause dramatic and, in some cases, irreversible changes…’ they can be ‘…overcome through a context-specific integrated governance approach’. AIM : Here we evaluate insights from the IPBES assessment in the context of South Africa and explore how these insights could inform the development of a national policy and strategy to address biological invasions. RESULTS : Trends and status of biological invasions in South Africa are similar to those seen globally, but there are some distinct local nuances. South Africa has: 1) a long history of invasions with negative impacts caused especially by invasive trees and freshwater fishes, whilst invasive marine invertebrates have transformed large parts of the coastline; 2) a long history of control (biological control was first implemented in 1913) with large-scale, state-run invasive species management programmes currently in place; 3) a comprehensive regulatory system (e.g., there is provision for beneficial invasive species to be used under permits); 4) relatively high levels of awareness and engagement (at least among some stakeholder groups); and 5) a well-connected community of practice. DISCUSSION : Efforts to limit introductions (intentional or unintentional) are difficult given South Africa’s extensive and porous borders and the pressing need to increase trade and travel. Regulatory and implementation efforts aimed at prevention are improving, with the newly established Border Management Authority aiming to integrate biosecurity interventions at ports of entry. Such integrated governance is, we argue, needed more broadly if affected sectors, society groups and stakeholders are to be effectively included in decision-making and management. A more systematic flow of information from observation to action is essential, as is better feedback between research, policy and implementation at all scales. Biological invasions will continue to pose threats, but many of these can be effectively mitigated through focussed interventions. Co-ordinating such interventions in the context of other cross-cutting global change challenges and initiatives is a cost-effective way of protecting and improving livelihoods, human health, quality of life and biodiversity.Item The role of hyperthermia in avian tolerance of hot and humid conditionsFreeman, Marc Trevor; Coulson, Bianca; Ngcamphalala, Celiwe A.; Makola, Mathome Otto; McKechnie, Andrew E. (Elsevier, 2025-12)Pronounced hyperthermia is thought to be important for thermoregulation during hot weather in animals inhabiting humid environments, where high atmospheric humidity constrains evaporative cooling. To assess the role of facultative, reversible hyperthermia in avian thermoregulation under hot, humid conditions, we examined how humidity influences thermoregulatory performance at air temperatures (Tair) exceeding normothermic body temperature (Tb) in red-billed queleas (Quelea quelea), a species capable of extreme hyperthermia (Tb > 48 °C). Using flow-through respirometry, we exposed queleas to Tair = 34 °C–50 °C at four experimental absolute humidities (6 g H2O m− 3, 13 g H2O m− 3, 19 g H2O m− 3, and 25 g H2O m−3). Across these humidity treatments, resting metabolic rate, evaporative water loss and maximum evaporative cooling efficiency responded similarly to increasing Tair, and maximum tolerable body temperature (Tbmax) remained consistent (48.60 ± 0.40 °C). Heat tolerance limits (HTL; environmental temperatures associated with thermoregulatory failure) averaged Tair = 48.41 ± 1.03 °C among humidity treatments. At Tair > ∼44.5 °C, evaporative cooling efficiency plateaued and queleas became poikilothermic, with Tb tracking Tair ≤ ∼48.4 °C. These findings demonstrate extreme hyperthermia tolerance can offset the constraints on evaporative cooling imposed by high humidity, allowing some birds to tolerate extreme combinations of heat and humidity. We propose a modification to an existing conceptual framework of the thermoregulatory roles of facultative hyperthermia to accommodate the effects of humidity on evaporative cooling and heat tolerance limits.Item Parental heat stress has transgenerational physiological- but not ecological-progeny fitness advantage in the larger grain borerMlambo, Shaw; Machekano, Honest; Mvumi, Brighton Marimanzi; Nyamukondiwa, Casper (Emerald, 2026-03)Climate change forecasts predict that global temperature and variability will continue rising owing to anthropogenic activities. This poses significant stress on ectotherms, whose bodily function depends on ambient temperatures. The ability of species to adapt within and/or across generations through phenotypic plasticity is thus a critical ecological topic. We investigated transgenerational thermal plasticity of the larger grain borer, Prostephanus truncatus, a devastating postharvest maize pest. Specifically, we tested the effects of parental exposure to sublethal heat stress (35 and 38 °C for 2 h; 80 % RH) on progeny thermal— and ecological—performance. Following acclimation, the colonies were separately maintained on shelled maize at optimum conditions of 32 °C at 65 ± 10 % RH. After 21 d, adult beetles were removed and the emerging progeny respectively labelled as F1 treatments (F1_35 °C and F1_38 °C). Subcultures from these 2 × F1 treatments were sampled in the same manner to obtain F2 (F2_35 °C and F2_38 °C) and subsequently F3 (F3_35 °C and F3_38 °C) generations which were then evaluated against parental (control) cultures maintained at optimal conditions 32 °C (P_32 °C). Our results showed that parental heat acclimation: (i) had transgenerational physiological— but not ecological-progeny fitness advantage; (ii) decreased critical thermal limit ranges; (iii) had cross-protection improvement in cold tolerance; and (iv) had transgenerational physiological responses that may last generations. Transgenerational plastic responses may help in understanding how species and ecosystems adapt to environmental temperature changes. This is the first report documenting transgenerational heat tolerance plasticity in P. truncatus. HIGHLIGHTS • Parental heat acclimation had transgenerational physiological- but not ecological-progeny fitness advantage. • Parental heat acclimation decreased progeny critical thermal limit ranges. • Parental heat acclimation had cross protective improvement in progeny cold tolerance. • Transgenerational physiological responses may last generations.Item Using physiology to unravel the implications of heatwaves for big brown bats (Eptesicus fuscus)De Mel, Ruvinda K.; Baloun, Dylan E.; Freeman, Marc Trevor; Probert, Anna F.; Cangemi, Taylor B.; Watters, Tina K.; Lausen, Cori L.; Kearney, Michael R.; Brigham, Mark; Czenze, Zenon J. (Company of Biologists, 2025-10)Nocturnal endotherms are vulnerable to high ambient temperatures (Ta) during the day when sequestered in retreat sites. Artificial roost design must therefore account for the thermal sensitivity of target species and the potential roost temperatures during heatwave conditions at installation sites. We recorded physiological responses of big brown bats (Eptesicus fuscus) under naturally observed roost temperatures using flow-through respirometry. We used the resulting data to parameterise a biophysical model with which we calculated the evaporative cooling requirements as percent body mass during the hottest day of 2023 and a heatwave during 2021. Our data revealed that the evaporative cooling requirements of bats roosting in certain artificial roosts would have exceeded the lethal dehydration threshold for both females and males during the 2021 heatwave (>22.1% body mass). Regardless of the availability of freestanding water in the environment, bats roosting in artificial roosts prone to overheating are at risk of lethal dehydration during heatwaves, even in high latitude habitats. Therefore, conservation management of small nocturnal endotherms should incorporate both physiological data and roost microclimate data when designing and deploying artificial roosts.Item Metabolic expenditure of submaximal locomotion in naked mole-rats (Heterocephalus glaber) and Damaraland mole-ratsThirkell, Jack E.; Bennett, Nigel Charles; Hart, Daniel William; Faulkes, Chris G.; Daley, Monica A.; Portugal, Steven J. (Company of Biologists, 2025-06)Despite extensive studies on the physiology of subterranean rodents, there is comparatively little work documenting the energetics specifically associated with their locomotory energetics. The energetic cost associated with burrowing is great and, in part, explains why subterranean species often maintain their burrows and tunnels across generations. Indeed, the digging metabolic rate of five African mole-rats has been determined to be between three and five times higher than their respective resting metabolic rate, yet the energetic cost of non-digging locomotion (i.e. walking) has not been recorded. Digging in most subterranean species tends to lead to specialisation of the forelimbs and teeth, which may significantly affect the energetic cost associated with non-digging locomotion. Unlike many comparably sized burrowing and tunnelling mammals, African mole-rats appear, superficially at least, to have almost identical forelimbs and hindlimbs. This study explored the locomotory energetics associated with sustained submaximal locomotion (i.e. fast walking; 10 cm s−1) in two African mole-rat species (Fukomys damarensis and Heterocephalus glaber), utilising open-flow respirometry and a small animal treadmill. The mean locomotory energetic rate for F. damarensis was a near 1-fold increase (91.4%) above resting metabolic rate and a 2-fold increase (203.2%) for H. glaber. Net cost of transport was higher overall for H. glaber (2.9±0.6 ml O2 kg−1 m−1) than for F. damarensis (2.4±0.5 ml O2 kg−1 m−1). A trade-off likely exists between limb specialisation for digging and economic locomotion, and thus for most obligately subterranean species, locomotion represents an energetic investment.Item Microallopatric speciation in southern African dung beetle genus macroderes driven by miocene aridification and ancestral flight lossDaniel, Gimo M.; Abdalla, Ishtiag H.; Scholtz, Clarke H.; Sole, Catherine L. (Wiley, 2025-12)AIM : Southern Africa harbours a diverse array of dung beetles (Scarabaeidae: Scarabaeinae), with many species endemic to the region. Despite this diversity, the historical drivers of their evolution remain largely unexplored. This study investigates the evolutionary history of the flightless dung beetle genus Macroderes, testing its monophyly and assessing the role of environmental transitions in shaping its diversification. Location Southwestern Africa, particularly the Greater Cape Floristic Region. Taxon The dung beetle genus Macroderes (Scarabaeidae: Scarabaeinae). METHODS : We conducted molecular phylogenetic analyses across multiple Macroderes species to test monophyly. Using BIOGeoBEARS, we inferred its ancestral range. To explore its biogeographical history and assess how late Cenozoic aridification in southwestern Africa shaped present-day microallopatric speciation patterns, we performed ancestral character reconstruction analyses. These examined Macroderes' origins, environmental adaptations (semi-arid vs. moist habitats), and the emergence of flight-lessness as an adaptive trait, specifically investigating whether the genus descended from volant or flightless ancestors. Bayesian diversification models evaluated diversification dynamics. RESULTS : Our findings support Macroderes' monophyly, with its most recent common ancestor (MRCA) originating in the late Miocene (~8.44 mya; 95% CI: 9.74–7.06 mya). The MRCA was flightless and associated with a semi-arid environment resembling the present-day Succulent Karoo biome. Subsequent diversification involved multiple southward colonisation events into Fynbos, indicating repeated environmental transitions. MAIN CONCLUSIONS : The evolutionary history of Macroderes highlights how aridification and flightlessness have shaped its diversification. Flightlessness in Macroderes is closely linked to adaptation to semi-arid environments, restricting dispersal and contributing to the genus's short-range endemicity. Repeated southward movement highlights the dynamic evolutionary history of Macroderes and the significant role of environmental transitions in shaping its lineage. Our findings highlight the role of historical climatic changes in driving speciation within flightless dung beetles.Item Diversification and biogeographic history of African dormice (genus Graphiurus) revealed by ultraconserved elements and mitochondrial dataOnditi, Kenneth Otieno; Demos, Terrence C.; Kerbis-Peterhans, Julian C.; Nicolas, Violaine; Mikula, Ondřej; Bryjová, Anna; Hounmavo, Amétépé; Monadjem, Ara; Bryja, Josef (Elsevier, 2026-04)The sub-Saharan Africa endemic dormouse genus Graphiurus is a morphologically diverse group of rodents that has lacked a genus-wide genetic framework, hindering inference of their evolution and biogeography. Here, we assembled the first comprehensive, range-wide genomic dataset for Graphiurus, including ultraconserved elements and the cytochrome b gene. We used phylogenetic reconstruction, divergence-time estimation, and ancestral area reconstruction to clarify biogeographic histories and evaluate how historical range dynamics may have influenced lineage diversification. Graphiurus is the earliest-diverging lineage within Gliridae sister to all other extant genera. Within Graphiurus, we recovered 24 molecular operational taxonomic units (MOTUs) forming two reciprocally monophyletic, deeply divergent clades: a West African lineage comprising three MOTUs and a pan-sub-Saharan Africa lineage comprising 21 MOTUs. Genetic distances between these clades are equal to or greater than those used to distinguish genera. Diversification within Graphiurus started in the middle Miocene, peaking in a rapid radiation during the Plio-Pleistocene. These diversification events coincided with increased climatic instability that fragmented forests into isolated refugia. Ancestral-area reconstructions suggest a Graphiurus origin in the Upper Guinean rainforest, followed by jump dispersal across the Afrotropics, with most subsequent divergences occurring in East Africa. As the first comprehensive phylogenetic analysis of Graphiurus, our study underscores the urgent need for an integrated taxonomic revision of the genus that couples genomic data with detailed morphology and critical re-examination of type material to resolve species limits and formally describe the recovered MOTUs. Many MOTUs appear range restricted, underscoring vulnerability to ongoing habitat loss within montane refugia. HIGHLIGHTS • The first phylogenomic dataset clarifies evolutionary relationships and highlights diversity within Graphiurus. • 24 highly supported genetic lineages in two deeply divergent, reciprocally monophyletic clades at genera level identified. • Divergence started in early Miocene, but major diversification aligned with Pliocene–Pleistocene climatic fluctuations. • Long-term habitat refugia in the Eastern African highlands were critical for lineage persistence. • An integrative taxonomic revision of the genus is needed.Item Strength in numbers : group size enhances individual survival and colony longevity in Damaraland mole-rats Fukomys damarensisJacobs, Paul Juan; Hart, Daniel William; Jarvis, Jennifer U.M.; Bennett, Nigel Charles (Elsevier, 2026-02)Cooperative behaviour presents an evolutionary paradox because although dispersal may increase direct fitness, many individuals forego reproduction to assist others. In arid-dwelling subterranean mammals, the high energetic costs of underground foraging, together with scarce and patchily distributed food resources are thought to have favoured the evolution of group living and cooperative breeding. These social systems are believed to enhance foraging efficiency and improve the survival prospects of individuals and groups. Using a longitudinal dataset from a wild population of Damaraland mole-rats (Fukomys damarensis) in arid central Namibia, we examine how group size predicts survival and persistence at both the individual and group levels. Our findings show that larger groups confer significant apparent survival benefits, that is the probability that an individual survives and remains available for recapture or resighting, reflecting both true survival and site fidelity, and also enhance colony persistence relative to solitary animals or pairs. We further demonstrate that these very small social-unit states are inherently unstable as without increases in group size, they are unlikely to persist within the population for extended periods. Larger groups clearly enhance survival, making remaining in the natal colony more beneficial than dispersing in an arid environment where dispersal is highly risky. HIGHLIGHTS • Dispersal is risky for Damaraland mole-rats in arid environments. • Solitary individuals and pairs did not persist for an extended period in the same state. • Larger group sizes provide survival benefits for individuals and for colonies.Item Large herbivores are linked to higher herbaceous plant diversity and functional redundancy across spatial scalesTrepel, Jonas; Atkinson, Joe; Le Roux, Elizabeth; Abraham, Andrew J.; Aucamp, Margerie; Greve, Michelle; Greyling, Marilize; Kalwij, Jesse M.; Khosa, Steven; Lindenthal, Lukas; Makofane, Caroline; Mokoena, Londiwe; Oosthuizen, Anika; Rech, Bent J.; Lundgren, Erick; Svenning, Jens-Christian; Buitenwerf, Robert (Wiley, 2026-01)Large herbivores can strongly influence plant communities. However, these effects are highly variable, potentially depending on the herbivore regime, that is, herbivore diversity and density. However, the role of the herbivore regime has been challenging to evaluate across spatial scales due to widespread defaunation and a lack of data on herbivore communities and their densities. Here, we investigated the effects of large herbivores along a gradient of trophic complexity (low to high herbivore diversity) and herbivory intensity (estimated from herbivore biomass and visitation frequency) on plant taxonomic and functional diversity at different scales (plot [n = 250], site [n = 50] and landscape [n = 10]) in 10 reserves in the savanna biome in South Africa. We found higher total plant species richness, driven by higher herbaceous (but not woody) plant species richness, in areas with higher herbivory intensity across multiple scales. While herbivores had no significant relationship with plant functional richness, we observed higher functional redundancy at all scales in areas more frequently visited by herbivores. Overall, herbivore–vegetation relationships were largely consistent across scales, and the strongest effects emerged at the largest scale. Our results show a positive relationship between large herbivores and both herbaceous plant species richness and plant functional redundancy, the latter suggesting higher vegetation resilience (the capacity of ecosystems to quickly recover from disturbances as different species compensate for the loss or decline of others). These effects are largely consistent across scales, indicating that the impact of herbivore regimes on plant communities is predominantly scale-independent and that large herbivores drive vegetation dynamics at both local and large scales. However, the stronger effects observed at the landscape scale imply that herbivore impacts manifest most prominently at larger scales. Altogether, our results suggest that restoring large herbivore populations can be expected to promote herbaceous plant diversity and ecosystem resilience.Item Breeding male mole-rats (Fukomys) use strong bites to defend reproductive monopolySumbera, Radim; Kraus, Andrea; Mikula, Ondrej; Okrouhlik, Jan; Measey, John; Begall, Sabine; Bennett, Nigel Charles; Zottl, Markus; Herrel, Anthony; Lovy, Matej (Nature Research, 2026-01)Bite force is a simple trait indicating an animal’s performance related to foraging, social dominance, and defence, all of which influence individual reproductive success. We examine the effect of breeding status on bite force in four social species of Fukomys, a genus of subterranean African rodents (Bathyergidae). These species are cooperative breeders, where reproduction is limited typically to a breeding pair. We collected in vivo bite force data, head width, and upper incisors width from 404 individuals from 75 families and tested whether breeders exhibit stronger bite force. We reveal that breeding males of all four species outperform non-breeders, with bite force in non-breeding males and females being 12% and 22% lower, respectively. In contrast, breeding females underperform relative to other categories, with bite force approximately 31% lower than in breeding males, and many are reluctant to bite. Head width and upper incisors width corroborate these findings. We propose that breeding males require a stronger bite force because of repeated competition with non-related males that may try to enter the family. In contrast, there is much less competition for the breeding position among females, as females rarely intrude into established families.