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Immunity and parasites have been linked to the success of invasive species. Especially lower parasite burden in invasive populations has been suggested to enable a general downregulation of immune investment (Enemy Release and Evolution of Increased Competitive Ability Hypotheses). Simultaneously, keeping high immune competence towards potentially newly acquired parasites in the invasive range is essential to allow population growth. To investigate the variation of immune effectors of invasive species, we compared the mean and variance of multiple immune effectors in the context of parasite prevalence in an invasive and a native Egyptian goose ( Alopochen aegyptiacus ) population. Three of ten immune effectors measured showed higher variance in the invasive population. Mean levels were higher in the invasive population for three effectors but lower for eosinophil granulocytes. Parasite prevalence depended on the parasite taxa investigated. We suggest that variation of specific immune effectors, which may be important for invasion success, may lead to higher variance and enable invasive species to reduce the overall physiological cost of immunity while maintaining the ability to efficiently defend against novel parasites encountered.

Vultures are avian obligate scavengers which provide important ecosystem services by efficiently removing carcasses from the landscape. Some species are now being observed feeding in coastal environments where they consume marine carcasses (i.e., whales, dolphins, seals and fish). On the African continent, only two species thus far have been reported to feed in the coastal ecosystems: the Lappet‐faced Vulture (Torgos tracheliotos) on the Skeleton Coast of Namibia and the Hooded Vulture (Necrosyrtes monachus) in southern Gambia. Here we report on the first observation of four White‐backed Vultures feeding on a Cape fur seal (Arctocephalus pusillus) killed by lions (Panthera leo). These observations carry several ecological and conservation implications and raise certain conservation concerns, including marine nutrients transfer and potential accumulation of marine environmental toxicants. Vultures are specialized scavengers that provide critical ecosystem services by clearing carcasses, though their activity in African coastal environments has previously been limited to only two documented species (i.e., the Lappet‐faced and the Hooded Vultures). This report documents the observation of White‐backed Vultures feeding on Cape fur seals, marking a significant expansion in the known foraging behavior of this species. These findings highlight important conservation considerations, specifically regarding the transfer of marine nutrients to terrestrial ecosystems and the potential risks associated with the exposure of vultures to the accumulation of marine‐derived toxins.

Many long‐distance migrating shorebird (i.e., sandpipers, plovers, flamingos, oystercatchers) populations are declining. Although regular shorebird monitoring programs exist worldwide, most estimates of shorebird population trends and sizes are poor or nonexistent. We built a state‐space model to estimate shorebird population trends. Compared with more commonly used methods of trend estimation, state‐space models are more mechanistic, allow for the separation of observation and state process, and can easily accommodate multivariate time series and nonlinear trends. We fitted the model to count data collected from 1990 to 2013 on 18 common shorebirds at the 2 largest coastal wetlands in southern Africa, Sandwich Harbour (a relatively pristine bay) and Walvis Bay (an international harbor), Namibia. Four of the 12 long‐distance migrant species declined since 1990: Ruddy Turnstone (Arenaria interpres), Little Stint (Calidris minuta), Common Ringed Plover (Charadrius hiaticula), and Red Knot (Calidris canutus). Populations of resident species and short‐distance migrants increased or were stable. Similar patterns at a key South African wetland suggest that shorebird populations migrating to southern Africa are declining in line with the global decline, but local conditions in southern Africa's largest wetlands are not contributing to these declines. State‐space models provide estimates of population levels and trends and could be used widely to improve the current state of water bird estimates.

Although communal goods are often critical to society, they are simultaneously susceptible to exploitation and are evolutionarily stable only if mechanisms exist to curtail exploitation. Mechanisms such as punishment and kin selection have been offered as general explanations for how communal resources can be maintained. Evidence for these mechanisms comes largely from humans and social insects, leaving their generality in question. To assess how communal resources are maintained, we observed cooperative nest construction in sociable weavers (Philetairus socius). The communal nest of sociable weavers provides thermal benefits for all individuals but requires continual maintenance. We observed cooperative nest construction and also recorded basic morphological characteristics. We also collected blood samples, performed next-generation sequencing, and isolated 2358 variable single nucleotide polymorphisms (SNPs) to estimate relatedness. We find that relatedness predicts investment in cooperative nest construction, while no other morphological characters significantly explain cooperative output. We argue that indirect benefits are a critical fitness component for maintaining the cooperative behavior that maintains the communal good.

Although Namibia is considered to be a largely arid country, it does support a wide range of wetland habitats, including ephemeral water bodies and pools of rainwater, artesian springs that support small perennial pools and streams, and large rivers in the northeastern section of the country. Rivers in this region drain areas north of Namibia that receive much more rainfall, and contribute most of the tropical species found in Namibia's wetlands. Researchers have identified 778 species of macro-invertebrates in Namibia's wetlands. The greatest levels of endemism occur among Ostracoda, Coleoptera, Diptera, Anostraca, and Amphipoda. An estimated 50 species of frogs live in Namibia, with three species endemic to the region. In addition, 114 species of freshwater fish have been identified in the region.

Namibia is an arid country but has a diverse array of wetland habitats ranging from ephemeral water bodies and rain-pools, artesian springs supporting small perennial pools and streams, to the large perennial rivers of the north-east with their associated floodplains. These rivers drain wetter areas north of Namibia and contribute many tropical species to Namibia's wetlands. There are 778 described species of macro-invertebrates representing eight phyla with 81 endemics. Many invertebrates still have to be identified or described but presently the greatest endemism occurs among the Ostracoda (18 species), Coleoptera (17), Diptera (14), Anostraca (six) and Amphipoda (five species). In total, Namibia has 50 species of frog with three endemics. No caecilians or salamanders occur in Namibia. There are 114 species of freshwater fish with five endemics. Most Namibian wetlands occur outside protected areas. Over-exploitation of wetland resources and flow regulation are currently major threats, but new environmental legislation being formulated is based on the goal of sustainable use.

Background Aim of this prospective study was to predict response to neoadjuvant therapy in breast cancer patients using an in vitro breast cancer spheroid model. Methods Three-dimensional spheroids were directly generated from fresh breast tumor biopsies of 78 patients eligible for neoadjuvant therapy. Cell survival was measured after in vitro exposure to the equivalent therapeutic agents in the breast cancer spheroid model. Treatment results in vitro were correlated with pathological complete response (pCR, i.e. ypT0 ypN0) determined at surgery. Results A mean cell survival of 21.8 % was found in the breast cancer spheroid model for 22 patients with pCR versus 63.8 % in 56 patients without pCR ( P  = .001). The area under the receiver operator characteristic curve to predict pCR was 0.86 (95 % CI: 0.77 to 0.96) for cell survival in vitro compared to 0.80 (95 % CI: 0.70 to 0.90) for a combined model of conventional factors (hormone- and HER2 receptor, and age). A cutoff at 35 % cell survival for the spheroid model was proposed. Out of the 32 patients with values below this threshold, 21 patients (65.6 %) and one patient (2.2 %) with a cell survival greater than 35 % achieved pCR respectively; (sensitivity 95.5 % (95 % CI: 0.86 to 1.00); specificity 80.4 % (95 % CI: 0.70 to 0.91)). Extent of residual disease positively correlated with increased cell survival ( P  = .021). Conclusion The breast cancer spheroid model proved to be a highly sensitive and specific predictor for pCR after neoadjuvant chemotherapy in breast cancer patients.