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Abstract African wild pigs have a contentious evolutionary and biogeographic history. Until recently, desert warthog (Phacochoerus aethiopicus) and common warthog (P. africanus) were considered a single species. Molecular evidence surprisingly suggested they diverged at least 4.4 million years ago, and possibly outside of Africa. We sequenced the first whole-genomes of four desert warthogs and 35 common warthogs from throughout their range. We show that these two species diverged much later than previously estimated, 400,000–1,700,000 years ago depending on assumptions of gene flow. This brings it into agreement with the paleontological record. We found that the common warthog originated in western Africa and subsequently colonized eastern and southern Africa. During this range expansion, the common warthog interbred with the desert warthog, presumably in eastern Africa, underlining this region’s importance in African biogeography. We found that immune system–related genes may have adaptively introgressed into common warthogs, indicating that resistance to novel diseases was one of the most potent drivers of evolution as common warthogs expanded their range. Hence, we solve some of the key controversies surrounding warthog evolution and reveal a complex evolutionary history involving range expansion, introgression, and adaptation to new diseases.

The response of prey to prédation risk varies through time and space. These responses relate to trade-offs between foraging and predator avoidance. Following the extirpation of predators from many landscapes, the responses related to predator avoidance may have been lost or diluted. Investigating the activity pattern of prey species on comparable landscapes with and without large predators provides an opportunity to understand how predators may shape prey activity and behaviour. Using camera trap data from neighbouring fenced sections of the Addo Elephant National Park (Eastern Cape, South Africa), we investigated the activity patterns of species exposed to large predators, where the predators were only present in one of the sections. Our results suggest that prey species at risk of prédation (e.g., buffalo, kudu and warthog) are more likely to be active diurnally when co-existing with nocturnally active predators, thereby reducing the activity overlap with these predators. In the absence of predators, kudu and buffalo were more active at night resulting in a low overlap in activity between sections. Warthog activity was predominantly diurnal in both sections, resulting in a high overlap in activity between sections. The presence of predators reduced the nocturnal activity of warthogs from 6 to 0.6 % of all warthog captures in each section. Elephants, which are above the preferred prey weight range of the predators and therefore have a low risk of predation, showed higher overlap in activity periodicity between predator-present and predator-absent areas. Our findings suggest that maintaining prey with their predators has the added benefit of conserving the full spectrum of prey adaptive behaviours.

Individuals can increase inclusive fitness benefits through a complex network of social interactions directed towards kin. Preferential relationships with relatives lead to the emergence of kin structures in the social system. Cohesive social groups of related individuals and female philopatry of wild boar create conditions for cooperation through kin selection and make the species a good biological model for studying kin structures. Yet, the role of kinship in shaping the social structure of wild boar populations is still poorly understood. In the present study, we investigated spatio-temporal patterns of associations and the social network structure of the wild boar Sus scrofa population in Białowieża National Park, Poland, which offered a unique opportunity to understand wild boar social interactions away from anthropogenic factors. We used a combination of telemetry data and genetic information to examine the impact of kinship on network cohesion and the strength of social bonds. Relatedness and spatial proximity between individuals were positively related to the strength of social bond. Consequently, the social network was spatially and genetically structured with well-defined and cohesive social units. However, spatial proximity between individuals could not entirely explain the association patterns and network structure. Genuine, kin-targeted, and temporarily stable relationships of females extended beyond spatial proximity between individuals while males interactions were short-lived and not shaped by relatedness. The findings of this study confirm the matrilineal nature of wild boar social structure and show how social preferences of individuals translate into an emergent socio-genetic population structure.

Studies that focus on single predator-–prey interactions can be inadequate for understanding antipredator responses in multi-predator systems. Yet there is still a general lack of information about the strategies of prey to minimize predation risk from multiple predators at the landscape level. Here we examined the distribution of seven African ungulate species in the fenced Karongwe Game Reserve (KGR), South Africa, as a function of predation risk from all large carnivore species (lion, leopard, cheetah, African wild dog, and spotted hyena). Using observed kill data, we generated ungulate-specific predictions of relative predation risk and of riskiness of habitats. To determine how ungulates minimize predation risk at the landscape level, we explicitly tested five hypotheses consisting of strategies that reduce the probability of encountering predators, and the probability of being killed. All ungulate species avoided risky habitats, and most selected safer habitats, thus reducing their probability of being killed. To reduce the probability of encountering predators, most of the smaller prey species (impala, warthog, waterbuck, kudu) avoided the space use of all predators, while the larger species (wildebeest, zebra, giraffe) only avoided areas where lion and leopard space use were high. The strength of avoidance for the space use of predators generally did not correspond to the relative predation threat from those predators. Instead, ungulates used a simpler behavioral rule of avoiding the activity areas of sit-and-pursue predators (lion and leopard), but not those of cursorial predators (cheetah and African wild dog). In general, selection and avoidance of habitats was stronger than avoidance of the predator activity areas. We expect similar decision rules to drive the distribution pattern of ungulates in other African savannas and in other multi-predator systems, especially where predators differ in their hunting modes.

Resource partitioning among mammalian savanna herbivores is thought to be predominantly driven by differences in body size. In general, large herbivore species utilize abundant low quality forage while small herbivores focus on scarcer high quality food items. However, in a natural system other factors such as digestive strategy, season and the presence of megaherbivores (body size > 1000 kg) are likely to complicate allometric predictions. Non-ruminants are probably better able to cope with abundant low quality food than ruminants of the same size causing a non-ruminant to act 'larger' than allometrically predicted. Also, the effect of alternating seasons with high and low food availability on diet choice and hence the competitive interactions between co-occurring herbivores is still poorly understood. Lastly, how megaherbivores deviate from allometric predictions (based on smaller species) is still not well quantified. In this study we examine resource partitioning among three ruminant and three non-ruminant grazers: impala, wildebeest, buffalo, warthog, zebra and white rhinoceros (megaherbivore) in the savanna of Hluhluwe iMfolozi Park, South Africa. We analysed habitat and diet overlap, specifically grass species (something not commonly investigated) and grass height eaten, in both the wet and the dry seasons. We found that habitat utilization differences among the species were generally small and did not vary between seasons. Diets within feeding patches overlapped during the wet season but highly diverged during the dry season. Body mass differences among species explained their dry season resource partitioning for all species except for comparisons with the megaherbivore (white rhino), while differences in digestive strategy were not related to niche overlap in either season. We conclude that savanna herbivores in this system coexist mostly through body size-driven resource partitioning in the dry-season, with the exception of the white rhino (megaherbivore).

Wildlife habitats in pastoral lands adjoining protected areas in east African savannas are getting progressively degraded, fragmented and compressed by expanding human populations and intensification of land use. To understand the consequences of these influences on wildlife populations, we contrasted the density and demography of 13 wild and three domestic large herbivores between the Masai Mara National Reserve and the adjoining pastoral ranches using aerial surveys conducted in the wet and dry seasons during 1977–2010. Species of different body sizes and feeding styles had different densities between landscapes and seasons. Small-sized herbivores, requiring short, nutritious grasses, and browsers were more abundant in the ranches than the reserve in both seasons. Medium-sized herbivores moved seasonally between landscapes. Larger-bodied herbivores, requiring bulk forage but less susceptible to predation, were more abundant in the reserve than the ranches. The proportions of newborn warthog ( Phacochoerus africanus ) and juvenile topi ( Damaliscus korrigum ) were higher in the ranches, with shorter grasses and lower predation risk than in the reserve. These results suggest that pastoral lands adjoining protected areas in African savannas are important as seasonal dispersal and breeding grounds for wild herbivores. However, human population growth and dramatic land use changes are progressively degrading wildlife habitats in pastoral areas, thus restricting the seasonal wildlife dispersal movements between the protected areas and adjoining pastoral lands. Conservation efforts should focus on (1) creating and maintaining functional heterogeneity in protected areas that mimic moderate pastoral grazing conditions to attract small and medium-bodied grazers and (2) securing dispersal areas, including corridors, to ensure continued seasonal large herbivore movements between protected and pastoral systems.

The rostral epidural rete mirabile (rete mirabile epidurale rostrale) is built of considerable small arterial vessels that anastomose with each other. This structure is formed as a result of the division of a large arterial vessel into many small arteries. Furthermore, on the other side of the rete mirabile, these small arteries are joined together to form one large artery, through which blood flows out of the rete mirabile. This system participates in decreasing the temperature of the brain and thus protects the body from thermal stress. Moreover, it influences body–water balance and has a crucial role in the retrograde transfer of neuropeptides. The goal of this study was to describe the rostral epidural rete mirabile and pathways that provide blood to this structure as well as compare it in selected Suiformes and hippopotamuses. The study was performed on desert warthogs (Phacochoerus aethiopicus), Eurasian wild boars (Sus scrofa), collared peccaries (Pecari tajacu), pygmy hippopotamuses (Choeropsis liberiensis), and common hippopotamuses (Hippopotamus amphibius). Preparations were made using the latex method and corrosion cast. An elongated shape characterizes its anatomy with a much wider rostral part than caudal part in the Eurasian wild boars, desert warthogs, and collared peccaries. The main source of blood was the branch to the rostral epidural rete mirabile branched off from the internal carotid artery. Moreover, blood enters the rete by the caudal branch and rostral branch to the rostral epidural rete mirabile. In hippopotamuses, the major source of blood was the rostral branches to the rostral epidural rete mirabile.

This study was undertaken with the intention of assessing abundance, species diversity, and distribution of medium and large diurnal mammals at the Humbo Community Based Forest Area, Ethiopia. The study area was stratified into three major habitats based on the vegetation cover of the area, such as riverine forest, bushland, and open grassland. The study in each vegetation type was surveyed using the transect method. It was conducted on foot along a randomly selected transect line. A total of eight large and medium mammalian species were recorded. The species recorded were Papio anubis, Sylvicapra grimmia, Tragelaphus scriptus, Chlorocebus pygerythrus, Tragelaphus strepsiceros, Lepus fagani, Phacochorus ethiopicus, and Panthera leo. During the survey, the leading order recorded was Artiodactyla followed by Primates. In terms of relative abundance, Anubis baboon (28.4% and 28.1%) and common duiker (19.4% and 11.4%) were the most abundant species, while warthog (12.1% and 8.9%) and lion (0.7% and 0.4%) were the least abundant during the wet and dry seasons, respectively. The highest number of mammalian species were distributed in bushland habitat during both wet (n = 7) and dry (n = 7) seasons. The highest Shannon-winner diversity index and evenness were obtained in the bushland habitat (1.70 and 2.21) during wet and dry seasons, respectively. Though the forest is the living place for various wild mammalian species, the conservation measures of the local community should also consider those species in line with the efforts that have been done on forest management practices.

Water, forage and predation constrain ungulate distributions in savannas. To understand these constraints, we characterized distributions of 15 herbivore species from water, locations of peak density and degree of clustering around the peaks using zero-inflated count data models and mapping census data collected in the Mara reserve and the adjoining pastoral ranches in Kenya during a wet and dry year. Herbivores followed a humped pattern ( n  = 46), suggesting constrained foraging in which they balance the benefits of proximity to water with the costs of foraging where food is depleted near water and travelling to more abundant food distant from water; an exponentially decreasing pattern ( n  = 11), indicating strong attraction to water or vegetation near water; or a uniform ( n  = 3) pattern. The details rather than the types of these patterns varied between years. Herbivores concentrated farther from water and more tightly around locations of their peak densities in the ranches than the reserve. Herbivores were more abundant and widely distributed from water in the wet than the dry year, and segregated along the distance-to-water gradient, presumably to minimize interspecific competition for food. Pastoralism compressed herbivore distributions and partially excluded some species (warthog, hartebeest, topi, wildebeest, zebra, eland, buffalo and elephant) from, while attracting others (Grant’s and Thomson’s gazelles, impala, giraffe) to the ranches, relative to the reserve. Regulating cultivation, fencing, settlements and livestock stocking levels in the ranches would allow continued wildlife access to water, reduce competition with, displacement or harassment of wildlife by people, livestock and dogs near water.

1. Rainfall is the prime climatic factor underpinning the dynamics of African savanna ungulates, but no study has analysed its influence on the abundance of these ungulates at monthly to multi-annual time scales. 2. We report relationships between rainfall and changes in age- and sex-structured abundances of seven ungulate species monitored monthly for 15 years using vehicle ground counts in the Maasai Mara National Reserve, Kenya. 3. Abundance showed strong and curvilinear relationships with current and cumulative rainfall, with older topi, Damaliscus korrigum (Ogilby); warthog, Phacochoerus aethiopicus (Pallas); waterbuck, Kobus ellipsyprimnus (Ogilby); and impala, Aepyceros melampus (Lichtenstein) responding to longer lags than younger animals, portraying carryover effects of prior habitat conditions. 4. The abundances of newborn calves were best correlated with monthly rainfall averaged over the preceding 5-6 months for topi, waterbuck, warthog, and 2 months for the migratory zebra Equus burchelli (Gray), but with seasonal rainfall averaged over 2-5 years for giraffe, Giraffa camelopardalis (L.); impala; and kongoni, Alcelaphus busephalus (Pallas). The cumulative late wet-season rainfall was the best predictor of abundance for quarter- to full-grown animals for most species. Monthly rainfall exerted both negative and positive effects on the abundances of zebra, impala and waterbuck. Ignoring age, both sexes responded similarly to rainfall. 5. Births were strongly seasonal only for warthog and topi, but peaked between August and December for most species. Hence abundance was strongly seasonal for young topi and warthog and the migratory zebra. Pronounced seasonality in births for warthog and topi obliterated otherwise strong relationships between abundance and rainfall when both month and rainfall were included in the same model. Aggregated density produced relationships with rainfall similar to those for fully grown animals, emphasizing the necessity of demographic monitoring to reliably reveal rainfall influences on ungulate abundance in the Mara. 6. Strong relationships between abundance and rainfall suggest that rainfall underpins the dynamics of African savanna ungulates, and that changes in rainfall due to global warming may markedly alter the abundance and diversity of these mammals. Ungulates respond to rainfall fluctuations through movements, reproduction or survival, and the responses appear independent of breeding phenology and synchrony, dietary guild, or degree of water dependence. Newborns and adults have contrasting responses to rainfall. Males and females respond similarly to rainfall when age is ignored.