Research Articles (Zoology and Entomology)

Permanent URI for this collectionhttp://hdl.handle.net/2263/1740

A collection containing some of the full text peer-reviewed/ refereed articles published by researchers from
the Department of Zoology and Entomology

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Staying alive : individual behavioral variation influences survival, but not reproductive success, in female group-living ground squirrels
Warrington, Miyako H.; Van der Marel, Annemarie; Sojka, Jennifer; Shofstall, Krista J.; Waterman, Jane M. (Wiley, 2025-07)
Animals living in harsh or unpredictable environments adopt adaptive strategies to improve their fitness, with behavioral variation playing a key role in shaping individual outcomes. We examined whether between-individual variation in behavioral traits (personality) was associated with reproductive success and survival in female Cape ground squirrels (Xerus inauris). Using a 10-year dataset (2011–2021), we quantified behavioral expressions of the animal's response to trapping and handling (trap response, as a proxy for docility), trapping rate (trappability, for boldness) and the number of different trapping locations an animal was trapped at (trap diversity, for exploration) and examined their associations with (1) annual reproductive success, (2) lifetime reproductive success, (3) annual survival, and (4) on-site persistence (a proxy for lifespan). Response measures taken during transfer from the cage, handling by a human observer, and whether individuals ran or walked after release were moderately repeatable. Trappability was also repeatable, while trap diversity was not. Trap response and trappability were positively correlated with survival, but not reproductive success. Females that easily transferred from the trap to the handling bag (more docile) had higher annual survival, while those that ran after release had longer lifespans. Individuals trapped at a higher rate (bolder) had higher annual survival. The absence of a relationship between behavioral traits and reproductive success in females suggests that other factors, such as group dynamics, social interactions, and maternal effects, may be more influential in explaining the high reproductive skew in female reproductive success. Overall, our findings highlight the role of individual behavioral variation in shaping survival outcomes while emphasizing the need for further research into the mechanisms driving reproductive success in this species.
Monthly and diel acoustic occurrence of four Baleen whale species in South African waters
Shabangu, Fannie Welcome; Hlati, Kuhle; Van den Berg, Marcel A.; Lamont, Tarron; Kirkman, Stephen P. (Wiley, 2025-08)
Understanding of the spatio-temporal occurrence of cetaceans post the whaling era is essential for protecting and improving management strategies of these marine mammals. To determine the monthly and diel acoustic occurrence of four baleen whale species relative to environmental conditions off the west coast of South Africa, we collected passive acoustic monitoring data within Child's Bank marine protected area in January and May through October 2024 at various water depths. Burst tonal calls of the southern African Bryde's whale offshore population were detected in January and May through July with the highest occurrence in January. Humpback whale songs and southern right whale gunshot sounds were detected from May through October with high occurrence in September and with smaller modes in other months. Antarctic minke whale bioduck calls were also found in June through October, showing high occurrence in August through October. Calls from an unknown source with similar characteristics to Antarctic minke whale bioduck calls were present in May, July, and August with the highest occurrence in August. Diel acoustic occurrence of Bryde's, southern right, Antarctic minke, and minke-like whale calls indicated that these animals vocalised more during the day while humpback whales were more vocally active at night. Sea surface height and sea surface temperature, either separately or in combination, were the most important predictors of whale acoustic occurrence, highlighting the influence of environmental conditions on the distribution, habitat selection, and ecology of these whales. Overall, this study advances our understanding of the movement, occurrence, and behavioural patterns of several baleen whales relative to environmental conditions. It also provides the first description of the southern African Bryde's whale offshore population's call characteristics, which will be useful at guiding future studies to acoustically differentiate between it and the inshore population.
Interspecies haptic sociality : an observation of grooming between two mongoose species
Smith, Kyle; Hepplewhite, Malcolm; San, Emmanuel Do Linh; Somers, Michael J. (Wiley, 2025-06)
Meerkats (Suricata suricatta) and yellow mongooses (Cynictis penicillata) share many behavioural characteristics and are known to, on rare occasions, live in close association through displayed cooperative vigilance and shared burrow use. Here, we describe the first visual observation of tactile social behaviour through grooming between a meerkat and a yellow mongoose in the Rietvlei Nature Reserve, South Africa. We hypothesise that the close relationship between the two species in the reserve may be a response to a combination of phylogenetic ties, shared behavioural traits, and the population collapse of meerkats in the reserve that exposed a vacant social niche. This observation of interspecific sociality further extends our knowledge of cooperation and group augmentation among meerkats, yellow mongooses and carnivores in general.
Despite potential risks African elephants do not always avoid mountaineering
Teixeira, Justine M.; Van der Westhuizen, Rickert; Shrader, A.M. (Adrian) (Wiley, 2025-07)
As herbivores forage, they move across a wide range of topographical features. Yet, they tend to avoid terrain such as steep slopes where energetic costs of movement are high and there is a greater risk of falls and tumbles. Recent studies suggest that African elephants (Loxodonta africana) avoid steep slopes (e.g., > 15°). However, in reserves with undulating topography, elephants may have to use steep slopes to obtain food, especially when availability is limited in more gradual areas. To explore this, we investigated slope use by elephants in the Ithala Game Reserve, South Africa, where the topography varies greatly and ranges between 400 to 1400 masl. Using 8.5 years of positional data, we examined how slope use varied between herd types (14 breeding herds and 13 males), habitat type and season (wet vs. dry). Elephants were found primarily on slopes < 30° (i.e., 95% of the locations), while 67% of the locations were on slopes < 15°, and 52% on slopes < 10°. Breeding herds used steeper slopes (mean = 12.6° ± 0.08 SE) than bulls (mean = 12.0° ± 0.8 SE). In addition, habitat influenced slope use, with the steepest slopes used in woodlands and the most gradual used in built-up areas and grasslands. However, these slope use differences were very small (i.e., 0.6° to 9.7°) and thus unlikely to be biologically meaningful. Rather, the ability to detect these slight differences was likely an artefact of our large sample size (N = 23,837 locations). Moreover, slope use did not vary between the wet and dry seasons. Nevertheless, 5% of all the elephant locations occurred on very steep slopes (i.e., > 30°) and 33% were on slopes > 15°, indicating that although they may prefer flat terrain, when required, elephants will mountaineer.
Threatened endemic arthropods and vertebrates partition their diets with non-native ants in an isolated island ecosystem
Tercel, Maximillian P.T.G.; Cuff, Jordan P.; Symondson, William O.C.; Moorhouse-Gann, Rosemary J.; Bishop, Tom Rhys; Cole, Nik C.; Jolin, Eric; Govier, Bethan; Chambon, Johannes; Mootoocurpen, Rouben; Goder, Martine; Vaughan, Ian P. (Wiley, 2025-07)
The success of non-native species depends on their ability to find food, which may ultimately lead to competition with native species and contribute to biodiversity loss in invaded ecosystems. Understanding which food resources are consumed is therefore crucial for evaluating how non-native species mechanistically fit into native biological communities. Non-native species may be predators or competitors of native species or may be consumed by native species as a novel source of nutrition, for example, and this can occur between both closely and distantly related species. Studies examining competitive interactions between non-native species and distantly related native taxa are relatively rare, largely because it is difficult to compare their diets using traditional methods. However, dietary DNA metabarcoding overcomes these limitations by enabling the construction of highly detailed food webs. Here, we use dietary DNA metabarcoding between two generalist native consumers—a reptile (Telfair's skink) and a Scolopendra centipede (Serpent Island centipede)—and the hyperabundant non-native ant community to test which consumer groups prey upon one another and partition food resources. To determine how non-native ants fit into a native community, we calculated dietary composition, niche overlap, and dietary diversity of ants, centipedes, and skinks on Round Island, a small 2.19-km2 oceanic island located 22.5 km north-east of Mauritius. We observed distinct partitioning of food resources among the three consumer groups—skinks, centipedes, and ants—and found that the level of predation between these groups varied. Skinks and centipedes frequently consumed non-native ants, which may represent an important nutritional resource for both native consumers. Dietary differences persisted through seasons despite large shifts in the availability of food and concomitant diet composition for all three consumers. We conclude that non-native ants fit into the biological community of Round Island as both prey for native consumers and extreme omnivorous generalists, but not necessarily at the expense of the native consumers because it is unlikely the consumers are competing for food resources. Our results suggest that abundant non-native generalists, which are highly invasive in much of their introduced range, can infiltrate native food webs without exerting strong competitive forces on other common native generalist species.
Creating the vision of rapid, repeatable, reactive data workflows for policy on biodiversity
Groom, Quentin; Abraham, Laura; Adriaens, Tim; Breugelmans, Lissa; Clarke, David A.; Di Musciano, Michele; Dove, Shawn; Estupinan-Suarez, Lina M.; Faulkner, Katelyn T.; Fernandez, Miguel; Hendrickx, Louise A.; Hui, Cang; Joly, Alexis; Kumschick, Sabrina; Langeraert, Ward; Martini, Matilde; Miller, Joe; Oldoni, Damiano; Pereira, Henrique; Preda, Cristina; Robertson, Tim; Rocchini, Duccio; Rodrigues, Andrew; Ryckewaert, Maxime; Seebens, Hanno; Sica, Yanina V.; Teixeira, Heliana; Trekels, Maarten; Vandaele, Toon; Wilson, John R.U.; Zengeya, Tsungai; Desmet, Peter (Wiley, 2025-07)
1. Effective biodiversity management and policymaking requires timely access to accurate and reliable scientific data on biodiversity status, trends and threats. However, current biodiversity monitoring processes are often time-consuming, complex and irreproducible. Moreover, the quality and types of biodiversity data are diverse, which challenges their integration and impedes effective monitoring. A major step to overcome such challenges would be the availability of standardized species occurrence data. However, challenges arise in aggregating and integrating these heterogeneous data with environmental and landscape data. 2. By creating standardized biodiversity data cubes and automated workflows for post-processing, we envision that (1) information from complex datasets will be available in a known format to efficiently communicate biodiversity variables to policymakers; (2) the adoption of repeatable Open Data workflows will make biodiversity data more accessible, efficient and cost-effective; and (3) cloud computing will make it easier to analyse large datasets, benefit from a broader range of models, share resources and work together on biodiversity projects. 3. This revolution in biodiversity monitoring will rely on community collaboration. By bridging the gap between policymakers' needs, bioinformation specialists' skills and data collectors' motivations, biodiversity monitoring can become a more inclusive and community-driven effort. As such, we advocate for the development of tools and workflows in close consultation with stakeholders to enhance the impact and use of biodiversity information. 4. Practical implication. The proposed approach faces challenges in maintaining software, data standards and addressing biodiversity data complexity. However, leveraging existing infrastructures like GBIF and Copernicus, and building on the knowledge from GEO and GEO BON offers a feasible path.
Assessing Gonipterus defoliation levels using multispectral unmanned aerial vehicle (UAV) data in Eucalyptus plantations
Nzuza, Phumlani; Schröder, Michelle L.; Heim, Rene J.; Daniels, Louis; Slippers, Bernard; Hurley, Brett Phillip; Germishuizen, IIaria; Sivparsad, Benice; Roux, Jolanda; Maes, Wouter H. (Elsevier, 2025-12)
Invasive insect pest Gonipterus sp. n. 2 (Coleoptera: Curculionidae) threatens Eucalyptus species, causing defoliation and yield loss through adult and larval feeding. Early detection is important for early intervention to prevent pest outbreaks. As conventional insect pest monitoring methods are time-consuming and spatially restrictive, this study assessed the potential of UAV monitoring. Multispectral imagery was obtained with Unmanned Aerial Vehicles (UAVs) across six different stands of young Eucalyptus dunnii with varying levels of Gonipterus sp. n. 2 infestations. Some stands were revisited, a total of 9 datasets were covered. Reference damage levels were obtained through visual assessments of (n = 89–100) trees at each site. Across sites, a decrease in canopy reflectance in both the visual and the near-infrared domains with increasing damage levels was consistently observed. Several vegetation indices showed consistent patterns, but none showed site independence. XGBoost, Support Vector Machine and Random Forest (RF) were used to predict damage levels using five input spectral data types. XGBoost performed best, closely followed by RF. Both models consistently selected very similar features. The best-performing models included reflectance, vegetation indices and grey-level co-occurrence matrix data. When data from 10 different wavelengths were used, the highest classification accuracy was 92 % across all sites in classifying defoliation levels. With a classical 5-band multispectral camera, accuracy was 88 %, but distinguishing medium damage from low remained challenging. However, the method was less reliable when trained and validated on separate fields. This study highlights the potential of multi-site datasets in increasing the model's generalization, using UAV based multispectral imagery to assess Gonipterus sp. n. 2 damage and demonstrating reliable upscaling from individual tree assessments to stand scale. However, it also recognises the difficulty of generating a robust model that performs well on untrained sites. HIGHLIGHTS • Canopy damage from Gonipterus sp. n. 2 was assessed across stands using UAV imagery, capturing defoliation, chlorophyll reduction. • The 5-band imagery perfomed comparable to the 10-band but was less effective at detecting subtle low vs no damage defoliation. • Similar pattern was observed across sites but absolute reflectance and vegetation indices are site specific.
The preference for energetic resources is positively associated with predatory activity in ants
Wilker, Icaro; Bishop, Tom Rhys; Lasmar, Chaim J.; Veiga, Dara; Souza, Leticia G.; Queiroz, Antonio C.M.; Feitosa, Rodrigo M.; Neundorf, Ana C.A.; Martins, Mila F.O.; Alves, Guilherme P.; Fontenele, Luane K.; Costa, Marilia M.S.; Ribas, Carla R. (Wiley, 2025-10)
1. Land use changes can alter resource availability and microclimate variables in tropical ecosystems, generally altering community structure by decreasing species richness and changing its composition. These changes affect foraging activity, nutrient preferences and consequently ecosystem functions. 2. Our aim was to assess how foraging activity and nutrient preference are influenced by changes in land use and microclimate. 3. We sampled ants (Formicidae) at 32 sites undergoing conversion from natural habitats to coffee systems in two Neotropical biomes: the Atlantic rainforest and the Cerrado. We assessed nutrient preference (amino acids, carbohydrates, lipids and sodium) and predation using mealworm larvae, while also measuring temperature and humidity. 4. We found the same ants foraged for different resources, likely because generalist species can perform these activities on the ground. Furthermore, foraging for energetic resources (carbohydrates and lipids) positively correlated with foraging for larvae. This indicates that the limitation of energetic resources can contribute to an increase in foraging and predatory activity. Moreover, ant preference for amino acids decreases with increasing temperature, indicating that ants prefer to consume energetic resources to support metabolic processes. 5. In conclusion, foraging is primarily carried out by generalist species. In addition, the preference for energetic nutrients, driven by energetic limitations, is linked to predatory activity. Moreover, ant species richness increases foraging for larvae, while rising temperatures decrease the preference for amino acids. Thus, conserving species richness and mitigating temperature increases may enhance larval foraging and support the insect predation function in Neotropical habitats.
Spatially-differentiated regulation of alien species can be improved using species distribution models : Psidium guajava in South Africa as a case study
Mbobo, Tumeka; Richardson, David M.; Datta, Arunava; Faulkner, Katelyn T.; Wilson, John R.U. (Wiley, 2025-10)
AIM : Biological invasions can generate conflicts between those who benefit from alien taxa and those threatened by subsequent invasions. Ideally, regulations should be proportionate to the level of threat—regulations perceived as unwarranted are likely to result in conflicts. We explore options for spatially differentiated regulation of alien species using Psidium guajava as a case study. LOCATION : South Africa. METHODS : Using various sources, we mapped sites across the country where guava is cultivated, naturalised, and has formed invasive monocultures. We identified areas under threat of invasions using species distribution models (SDMs). RESULTS : Our models predict that guava invasions are likely along South Africa's east coast. However, the niche dynamic indices indicate a larger cultivated niche than a naturalised niche, suggesting that there are areas in South Africa suitable for guava cultivation where invasions are unlikely. Our SDMs suggest that almost half the area regulated at the provincial level does not require regulation; this spatial over-regulation could be reduced to ~20% if regulations were at the next lower political level. CONCLUSIONS : We recommend that current regulation of guava be aligned to the level of threat. For example, guava is currently regulated in the North-West province, but we found no records of naturalisation and SDMs suggest the climate is not suitable. However, we note a trade-off between the resolution of the regulations and enforceability. We argue that: at lower levels there will be dispersal of fruits between unregulated and regulated areas as the distances between areas will be short; the SDMs produced here are not of sufficient resolution to accurately predict local conditions; and very localised variations in regulations will be complicated to enforce. Although SDMs can easily be over-interpreted, we believe that their judicious use provides a valuable method of interpreting field information in a form useful for regulators so conflicts can be avoided.
Effective homemade V8 juice formulation as alternative suitable medium for culturing Phytophthora infestans
Muhorakeye, Marie C.; Namikoye, Everlyne S.; Khamis, Fathiya Mbarak; Wanjohi, Waceke; Akutse, Komivi S. (Springer, 2025-10)
A suitable growth medium is essential for isolating, studying, and managing pathogens. To mitigate the importation dependence and availability of commercial V8 growth medium, three V8 juice formulations (F1, F2, and F3) were developed and tested in this study for their potential to stimulate the growth and sporulation of Phytophthora infestans at different growing temperatures in comparison with commercial V8 juice formulation. The results showed that the three V8 juice forms successfully induced the growth and sporulation of P. infestans at varied temperature regimes. However, V8 juice F2-based medium significantly caused quicker growth of P. infestans and increased in number and size of sporangia as well as the commercial formulation (FC) of V8 juice. In addition, the pathogen successfully grew at 15 ± 2 °C, 20 ± 2 °C, and 25 ± 2 °C; however, the plates incubated at 20 ± 2 °C displayed faster growth of the colony as compared to those incubated at the other two temperatures. Furthermore, more spores were obtained on the plates incubated at 15 ± 2 °C compared to the plates incubated at 20 ± 2 °C and 25 ± 2 °C. Overall, the V8 F2-based media was more suitable for P. infestans growth and sporulation. This finding is critical since it helps to lessen reliance on V8 juice imports and increases available V8 juice to culture or mass produce the pathogen. Consequently, further research is encouraged for sustainable management of P. infestans. HIGHLIGHTS • Homemade V8 alternative formulations support P. infestans growth and sporulation. • However, F2 formulation performs similarly to the commercial with quicker growth and increased number and size of sporangia. • The pathogen grew best at 20 °C, but produced more spores at 15 °C. • Local V8 alternatives can minimize dependency on imports and support future research on managing the pathogen.
A database on the historical and current occurrences of snakes in Eswatini
Monadjem, Ara; Boycott , Richard C.; Litscha-Koen, Thea; Kane, Adam; Dlamini, Wisdom M.; Mmema, Lindelwa; Strutton, Katharine L.; Hlophe , Zakhele; Padidar, Sara (Oxford University Press, 2025-07)
Snakes are among the most difficult terrestrial vertebrates to survey, resulting in poor distributional information on most species. This database comprises of 3812 records of 58 species of snakes in 37 genera reported from within the boundaries of Eswatini. The data were compiled from multiple sources including museum specimens, iNaturalist records, literature records, and snake rescue operations. For each specimen reported in the database, we provide the scientific name, latitude and longitude coordinates, and location. Most records also have an associated date. This comprehensive database will be useful to biodiversity experts, conservationists, medical practitioners, researchers, and snake enthusiasts, especially for mapping and modelling snake distributions in the country. To allow easy viewing of the distribution of snakes in the country, we provide an online visualization tool, which should allow a greater number of non-scientists to utilize this database.
Enhancing plantation forest sustainability : a review of Eucalyptus defence mechanisms to foliar fungal pathogens
Solis, Myriam; Hammerbacher, Almuth; Wingfield, Michael J.; Naidoo, Saloshnee (Springer, 2025-02)
PURPOSE OF THE REVIEW : In this review, we synthesize knowledge generated over many decades on the main defence responses of Eucalyptus to fungal leaf pathogens with the aim of identifying targets for breeding disease tolerant trees. We highlight physiological and molecular traits associated with host defence in relation to pathogen life-style. Overall, the purpose of this review is to identify resistance mechanisms that offer improved resilience of Eucalyptus plantations in the face of increasing threats by foliar fungal pathogens. The broad aim is to promote sustainable forestry through appropriate selection of resistance traits in trees that are widely planted for commercial timber production. RECENT FINDINGS : Eucalyptus is among the most important tree genera planted for commercial timber production worldwide. Numerous foliar pathogens have been reported on these trees in the last 30 years with numbers of recent reports increasing exponentially. The majority of these diseases affect the leaves and shoots of the trees. Knowledge on resistance traits in Eucalyptus to fungal foliar pathogens is limited. This is in part due to the high intra- and inter-species variation in molecular and physiological responses of the host and variation in responses to different pathogens, especially those with different trophic modes. A well-founded understanding of such host responses will provide valuable knowledge required to maintain healthy, sustainable Eucalyptus plantations, especially in the face of changing environmental conditions, where new diseases are caused by fungi previously not considered relevant. SUMMARY : Foliar diseases are among the most important challenges for Eucalyptus plantations globally. The effects of climate change and new or more serious outbreaks present an important threat to the sustainability of Eucalyptus plantations worldwide. Due to restrictions on the use of chemicals, more feasible solutions for disease management lie in selecting planting material with resistance traits. To achieve that goal, it is essential to understand the most important physiological and molecular responses of Eucalyptus to infection by pathogens that infect their foliar tissues. In this review we summarise the available knowledge of the main physiological defence barriers and genetic traits that play key roles in the broad defence against foliar fungal pathogens. Furthermore, we consider defence pathways that are specifically related to the lifestyle and trophic mode of the pathogens. In order to ensure the future sustainability of Eucalyptus plantations, it will be necessary to understand how disease resistance is affected by climate change, as well as the adaptability of the hosts and pathogens to newly emerging environmental conditions.
Responses of fruit flies (Diptera: Tephritidae) to protein bait : effects of tree canopy, species, physiological state and weather
Ramaoka, Msizi Ronald; Manrakhan, Aruna; Weldon, Christopher W. (Elsevier, 2025-11)
The application of protein baits forms the core of fruit fly (Diptera: Tephritidae) control measures in many orchard environments. Protein baits target adult fruit flies, which need protein for reproductive maturation. A proper understanding of the factors influencing fruit fly responses to protein is required to optimise control outcomes. In this study, responses to protein bait by three fruit fly species, Ceratitis capitata (Wiedemann), C. cosyra (Walker), and Bactrocera dorsalis (Hendel), were investigated. This was done in two field cages erected over lemon trees within an orchard. The response of each species to protein bait presented as a station and positioned at different heights within the tree canopy was evaluated. For each species, effects of fly age, sex, and nutritional status were evaluated under conditions of varying temperature and relative humidity. The highest response occurred when protein baits were placed in the middle to upper tree canopy. Species, nutritional status, sex and age also affected protein foraging. Ceratitis capitata responded more to bait compared to B. dorsalis and C. cosyra. The lowest response to protein bait was by one-day-old protein fed flies, while 10-day-old protein-deprived flies were most responsive. Protein deprived females were more attracted to protein than males fed the same diet. Flies responded to bait when temperatures were between 20 and 30 °C. Based on the results, the success of protein baits in controlling fruit flies in a tree canopy is height dependent and can be lower in areas with alternative protein sources.
Short communication: Elevated testosterone correlates with enhanced innate immune function in a cooperatively breeding rodent
Wallace, Kyra Mary Elizabeth; Venter, S.N. (Stephanus Nicolaas); Bennett, Nigel Charles; Hart, Daniel William (Elsevier, 2025-10)
In many vertebrates, elevated testosterone is believed to compromise the immune function, reflecting a trade-off between reproduction and survival. However, such trade-offs may potentially be relaxed in cooperative breeders, where social conflict and sexual selection are reduced. We investigated the relationship between testosterone, cortisol, and innate immunity in captive male Damaraland mole-rats (Fukomys damarensis), a eusocial rodent with minimal aggression-driven reproductive competition. Using microbial killing assays (MKAs) and white blood cell counts as proxies of immune function, we found that urinary testosterone concentration was positively correlated with immune strength. Males with higher urinary testosterone concentrations exhibited significantly greater antimicrobial capacity and elevated total white blood cell counts. However, urinary testosterone was unrelated to independent immune cell differentials. While, reproductive status, age, body mass, and urinary cortisol concentrations had a limited effect on any immune metric. These findings, while correlative, challenge traditional endocrine-immune trade-off models and infer that, in this species, testosterone may signal condition rather than impose immunosuppressive costs.
The first teratological case for the Australian Omorgus Erichson, 1847 species (Coleoptera, Scarabaeoidea, Trogidae)
Da Costa-Silva, Vinicius (Senckenberg Deutsches Entomologisches Institut, 2025-05-28)
A new case of hemidystrophy in Trogidae is here described and illustrated. The teratological specimen was identified as a male of Omorgus (Omorgus) alternans (MacLeay, 1827), being the first record of a teratological specimen of a trogid from Australia. While teratological cases provide limited taxonomic insights, they offer significant understanding of the environmental influences on insect development. The study emphasizes the importance of documenting such anomalies, contributing to the broader knowledge of developmental biology in insects, particularly within the under-researched Australian Trogidae.
Population genetic analysis of Aedes aegypti reveals evidence of emerging admixture populations in coastal Kenya
Mulwa, Francis; Balcazar, Dario; Langat, Solomon; Mutisya, James; Chelangat, Betty; McBride, Carolyn S.; Rose, Noah; Powell, Jeffrey; Sang, Rosemary; Bastos, Armanda D.S.; Gloria-Soria, Andrea; Lutomiah, Joel (Public Library of Science, 2025-05)
BACKGROUND : The Aedes aegypti mosquito is widespread in tropical and subtropical regions. There are two recognized subspecies; the invasive Aedes aegypti aegypti (Aaa) and the ancestral Aedes aegypti formosus (Aaf). Aaf is common throughout Kenya whereas Aaa, which was historically confined to coastal regions, has undergone a range expansion. In areas of sympatry, gene flow may lead to admixed populations with potential differences in vectorial capacity. We hypothesize that coastal Ae. aegypti populations have a higher proportion of Aaa ancestry than those from inland locations of Kenya, influenced by their distance to the coast. METHODOLOGY : Adult Ae. aegypti mosquitoes were collected using Biogent (BG) sentinel traps baited with carbon-dioxide (CO2) from cities and towns along the Kenyan northern transport corridor. Aedes aegypti population structure, genetic diversity, and isolation by distance were analyzed using genome-wide single nucleotide polymorphism (SNPs) datasets generated with an Ae. aegypti microarray chip targeting ≈50,000 SNPs. Kenyan Aedes aegypti populations were placed into a global context within a phylogenetic tree, by combining the Kenyan dataset with a previously published global database. RESULTS : A total of 67 Ae. aegypti mosquitoes population from Kenya were genotyped, we found that western Kenya Ae. aegypti constitute a genetically homogenous population that clusters with African Aaf, whereas coastal mosquitoes showed evidence of admixture between the two subspecies. There was a positive correlation (Observation = 0.869, p = 0.0023) between genetic distance (FST) and geographic distance, suggesting isolation by distance. The phylogenetic analysis and the genetic structure analysis suggest that an Asian Aaa population is the source of Aaa invasion into Kenya. CONCLUSIONS : These results provide evidence of an emerging admixed population of Ae. aegypti in coastal Kenya between the sylvatic Aaf and the domesticated-human preferring Aaa. The observed gene flow from Aaa into Kenya may positively influence Ae. aegypti vectorial capacity, potentially increasing human feeding preference, biting rates and vector competence and could be promoting the observed dengue and chikungunya outbreaks. AUTHOR'S’ SUMMARY Aedes aegypti is of great public health concern due the viruses they transmit. The vector is highly invasive and is expanding to new geographic regions, quickly adapting to new environment. This study focuses in understanding the genetic structure of Ae. aegypti in cities along the northern transport corridor in Kenya, which are at risk of vector invasion. We analyzed Ae. aegypti populations using a panel of Single Nucleotide Polymorphism (SNPs) markers distributed across the genome. Our analysis shows admixture population in the coastal region between Aaf and Aaa, with Asian mosquitos being the putative source of Aaa ancestry, while the western populations are more related to African Aaf. This research provides a broad picture of the nature and dynamics of the Ae. aegypti populations across Kenya and sets the bases for further genetic studies focused on improving vector control strategies and developing novel mosquito control methods.
Molecular characterisation of tick-borne pathogens in cattle in Kenya : insights from blood, ticks, and skin swab analyses
Getange, Dennis; Mukaratirwa, Samson; Bargul, Joel L.; Khogali, Rua Khogali Ibrahim; Ng'iela, John; Kabii, James; Masiga, Daniel K.; Villinger, Jandouwe (BioMed Central, 2025-10)
BACKGROUND : Ticks pose a major threat to livestock and human health in sub-Saharan Africa, with climate change and pastoral movements fueling their spread. Few studies have integrated multiple sample types to characterize tick-borne pathogens (TBPs) in cattle in Kenya. This knowledge gap hinders the development of effective surveillance and control strategies, leaving vulnerable populations and their livestock susceptible to these persistent threats. METHODS : We screened 280 bovine blood samples, 589 tick pools, and 284 non-invasive skin swabs from cattle in northern (Marsabit) and southern (Kajiado) Kenya by high-resolution melting analysis and Sanger sequencing of PCR products. RESULTS : Rhipicephalus spp. (47.1%), Hyalomma spp. (30.8%), and Amblyomma spp. (22.1%) were prevalent, with Rhipicephalus evertsi only found in Kajiado and Rhipicephalus camicasi in Marsabit. In blood, Anaplasma spp. (62.9%; A. marginale, A. platys, A. ovis) and Theileria spp. (34.6%; T. velifera, T. mutans) were dominant. Tick pools harbored Coxiella burnetii, Rickettsia africae, Rickettsia aeschlimannii, Anaplasma marginale, Theileria velifera, T. ovis, and Babesia occultans, and for the first time two co-circulating Ehrlichia ruminantium strains (Welgevonden and Kumm2). Notably, C. burnetii and T. ovis were detected only in Marsabit, and T. mutans only in Kajiado. Skin swabs from tick predilection sites (ears, anal region) yielded R. africae, R. aeschlimannii, and T. velifera at low positivity, while nose swabs were negative. CONCLUSIONS : Detection of zoonotic pathogens such as C. burnetii and R. africae underscores critical public health risks, and co-infections in cattle reinforce the need for robust, integrated surveillance. Although skin swabs demonstrated limited diagnostic yield, they remain a promising non-invasive sampling approach. These findings highlight the value of targeted acarological research and coordinated control programs under a One Health framework.
Trophic niche of invasive murid rodents in urban and peri-urban areas in South Africa : insights from stable isotope analysis
Ringani, Gordon V.; Chimimba, Christian Timothy; Pirk, Christian Walter Werner; Zengeya, Tsungai Alfred (BioMed Central, 2025-10)
There are three invasive Rattus species (R. norvegicus, R. rattus, R. tanezumi) that are known to occur in South Africa. The three Rattus species are widespread in urban and peri-urban areas where they have had a significant impact on human health, infrastructure, and biodiversity. There is, however, limited information on their trophic ecology and on how factors that affect access to, and utilization of, food resources facilitate successful establishment. This study applied stable isotope analysis (SIA) to assess the trophic niches of the three Rattus species across selected urban and peri-urban landscapes in Gauteng Province. The three Rattus species occurred allopatrically: R. norvegicus in urban areas (Alexandra and Tembisa townships), R. rattus in the peri-urban University of Pretoria Experimental Farm, and R. tanezumi in peri-urban areas near Hammanskraal. Rattus tanezumi and R. rattus exploited broader food resources in peri-urban areas that are used for agricultural activities, while R. norvegicus had a more restricted niche in urban environments. Niche breadth expanded in summer, reflecting seasonal food availability, while sex- and age-related differences suggested subtle differences in feeding strategies, although the results were inconsistent across species and sites. Although some limitations, such as the fact that the three Rattus species were sampled in allopatry and missing baseline resources constrained interpretation, the study provides insights into how invasive rats adapt to different environments. Future research combining stable isotope analysis with long-term monitoring data will be essential to clarify niche partitioning and guide effective management of invasive rat populations.
Determinants of mating success in a lek-mating species
Queffelec, Josephine; Allison, Jeremy D.; Slippers, Bernard; Greeff, Jacobus Maree (Wiley, 2025-11)
• Leks are male-biased aggregations formed for mating, where sperm is the only resource acquired by visiting females. • One of the many advantages of leks is the possibility to efficiently assess the quality of potential mates by comparing aggregated individuals of the same sex with one another. • When direct mate choice occurs in a lekking species, it is often exhibited by females, but some studies have also demonstrated the presence of male mate choice. • We investigate mate choice in the lek-forming European woodwasp, Sirex noctilio. • We determine the importance of age and size as predictors of mating success. • We demonstrate that mating is not random and that male and female traits affect mating success. • Age plays an important role in mating success in both males and females, with older males mating more and younger females being more attractive and more receptive to mating. • Relative male size seems to play a role in mating success, with males being more successful when attempting to mate with females that are larger than they are.
Unsustainable anthropogenic mortality threatens the long-term viability of lion populations in Mozambique
Almeida, Joao; Briers-Louw, Willem D.; Jorge, Agostinho; Begg, Colleen; Roodbol, Marnus; Bauer, Hans; Loveridge, Andrew; Wijers, Matthew; Slotow, Rob; Lindsey, Peter Andrew; Everatt, Kristoffer; Rosier, Holly; Nazerali, Sean; Roxburgh, Lizanne; Pereira, Hugo; Da Conceicao, Mercia; Araman, Armindo; Abrao, Osvaldo J.; Leslie, Alison J.; Steinbruch, Franziska; Naude, Vincent N.; Nicholson, Samantha K. (Public Library of Science, 2025-06)
Anthropogenic mortality is a pervasive threat to global biodiversity. African lions (Panthera leo) are particularly vulnerable to these threats due to their wide-ranging behaviour and substantial energetic requirements, which typically conflict with human activities, often resulting in population declines and even extirpations. Mozambique supports the 7th largest lion population in Africa, which is recovering from decades of warfare, while ongoing conflicts and broad-scale socio-economic fragility continue to threaten these populations. Moreover, there are concerns that Mozambique represents a regional hotspot for targeted poaching of lions which fuels a transnational illegal wildlife trade. This study aimed to quantify the longitudinal impact of anthropogenic mortality on lion populations in Mozambique. Using national population estimates and monitoring records, we performed forward simulation population viability modelling incorporating detection-dependent population trends and varying scales of anthropogenic mortality. Between 2010–2023, 326 incidents of anthropogenic mortality involving 426 lions were recorded. Bushmeat bycatch and targeted poaching for body parts were the greatest proximate causes of lion mortality (i.e., 53% of incidents), increasing significantly over time and acting as cryptic suppressors of regional population recovery, followed by legal trophy hunting (i.e., 33%), and retaliatory killing (i.e., 13%). Our findings suggest that resilience to anthropogenic threats is largely a function of lion population size as well as resource and management capacity. For instance, projections suggest that the lion population in Niassa Special Reserve will likely remain stable despite comparatively high levels of anthropogenic mortality, although further escalation may precipitate decline. Conversely, the lion population in Limpopo National Park is projected to become extirpated by 2030 without the buffering effect of its neighbouring source population in Kruger National Park. These unsustainable levels of anthropogenic mortality threaten the long-term viability of lion populations in Mozambique, requiring urgent national-level action and public-private partnerships to support site security, monitoring, and policy enforcement.

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