Novel insights into the genetic diversity of Balantidium and Balantidium-like cyst-forming ciliates

Balantidiasis is considered a neglected zoonotic disease with pigs serving as reservoir hosts. However, Balantidium coli has been recorded in many other mammalian species, including primates. Here, we evaluated the genetic diversity of B. coli in non-human primates using two gene markers (SSrDNA and ITS1-5.8SDNA-ITS2). We analyzed 49 isolates of ciliates from fecal samples originating from 11 species of captive and wild primates, domestic pigs and wild boar. The phylogenetic trees were computed using Bayesian inference and Maximum likelihood. Balantidium entozoon from edible frog and Buxtonella sulcata from cattle were included in the analyses as the closest relatives of B. coli, as well as reference sequences of vestibuliferids. The SSrDNA tree showed the same phylogenetic diversification of B. coli at genus level as the tree constructed based on the ITS region. Based on the polymorphism of SSrDNA sequences, the type species of the genus, namely B. entozoon, appeared to be phylogenetically distinct from B. coli. Thus, we propose a new genus Neobalantidium for the homeothermic clade. Moreover, several isolates from both captive and wild primates (excluding great apes) clustered with B. sulcata with high support, suggesting the existence of a new species within this genus. The cysts of Buxtonella and Neobalantidium are morphologically indistinguishable and the presence of Buxtonella-like ciliates in primates opens the question about possible occurrence of these pathogens in humans

High prevalence and diversity of species D adenoviruses (HAdV-D) in human populations of four Sub-Saharan countries

Abstract. Background: Human adenoviruses of species D (HAdV-D) can be associated with acute respiratory illness, epidemic ker

Assessing Host-Virus Codivergence for Close Relatives of Merkel Cell Polyomavirus Infecting African Great Apes

It has long been hypothesized that polyomaviruses (PyV; family Polyomaviridae) codiverged with their animal hosts. In contrast, recent analyses suggested that codivergence may only marginally influence the evolution of PyV. We reassess this question by focusing on a single lineage of PyV infecting hominine hosts, the Merkel cell polyomavirus (MCPyV) lineage. By characterizing the genetic diversity of these viruses in seven African great ape taxa, we show that they exhibit very strong host specificity. Reconciliation analyses identify more codivergence than noncodivergence events. In addition, we find that a number of host and PyV divergence events are synchronous. Collectively, our results support codivergence as the dominant process at play during the evolution of the MCPyV lineage. More generally, our results add to the growing body of evidence suggesting an ancient and stable association of PyV and their animal hosts

Cytomegalovirus distribution and evolution in hominines

Herpesviruses are thought to have evolved in very close association with their hosts. This is notably the case for cytomegaloviruses (CMVs; genus Cytomegalovirus) infecting primates, which exhibit a strong signal of co-divergence with their hosts. Some herpesviruses are however known to have crossed species barriers. Based on a limited sampling of CMV diversity in the hominine (African great ape and human) lineage, we hypothesized that chimpanzees and gorillas might have mutually exchanged CMVs in the past. Here, we performed a comprehensive molecular screening of all 9 African great ape species/subspecies, using 675 fecal samples collected from wild animals. We identified CMVs in eight species/subspecies, notably generating the first CMV sequences from bonobos. We used this extended dataset to test competing hypotheses with various degrees of co-divergence/number of host switches while simultaneously estimating the dates of these events in a Bayesian framework. The model best supported by the data involved the transmission of a gorilla CMV to the panine (chimpanzee and bonobo) lineage and the transmission of a panine CMV to the gorilla lineage prior to the divergence of chimpanzees and bonobos, more than 800,000 years ago. Panine CMVs then co-diverged with their hosts. These results add to a growing body of evidence suggesting that viruses with a double-stranded DNA genome (including other herpesviruses, adenoviruses, and papillomaviruses) often jumped between hominine lineages over the last few million years.Peer Reviewe

Novel insight into the genetic diversity of strongylid nematodes infecting South-East and East Asian primates

With many non-human primates (NHPs) showing continued population decline, there is an ongoing need to better understand their ecology and conservation threats. One such threat is the risk of disease, with various bacterial, viral and parasitic infections previously reported to have damaging consequences for NHP hosts. Strongylid nematodes are one of the most commonly reported parasitic infections in NHPs. Current knowledge of NHP strongylid infections is restricted by their typical occurrence as mixed infections of multiple genera, which are indistinguishable through traditional microscopic approaches. Here, modern metagenomics approaches were applied for insight into the genetic diversity of strongylid infections in South-East and East Asian NHPs. We hypothesized that strongylid nematodes occur in mixed communities of multiple taxa, dominated by Oesophagostomum, matching previous findings using single-specimen genetics. Utilizing the Illumina MiSeq platform, ITS-2 strongylid metabarcoding was applied to 90 samples from various wild NHPs occurring in Malaysian Borneo and Japan. A clear dominance of Oesophagostomum aculeatum was found, with almost all sequences assigned to this species. This study suggests that strongylid communities of Asian NHPs may be less species-rich than those in African NHPs, where multi-genera communities are reported. Such knowledge contributes baseline data, assisting with ongoing monitoring of health threats to NHPs

Plasticity in the Human Gut Microbiome Defies Evolutionary Constraints

The gut microbiome of primates, including humans, is reported to closely follow host evolutionary history, with gut microbiome composition being specific to the genetic background of its primate host. However, the comparative models used to date have mainly included a limited set of closely related primates. To further understand the forces that shape the primate gut microbiome, with reference to human populations, we expanded the comparative analysis of variation among gut microbiome compositions and their primate hosts, including 9 different primate species and 4 human groups characterized by a diverse set of subsistence patterns (n = 448 samples). The results show that the taxonomic composition of the human gut microbiome, at the genus level, exhibits increased compositional plasticity. Specifically, we show unexpected similarities between African Old World monkeys that rely on eclectic foraging and human populations engaging in nonindustrial subsistence patterns; these similarities transcend host phylogenetic constraints. Thus, instead of following evolutionary trends that would make their microbiomes more similar to that of conspecifics or more phylogenetically similar apes, gut microbiome composition in humans from nonindustrial populations resembles that of generalist cercopithecine monkeys. We also document that wild cercopithecine monkeys with eclectic diets and humans following nonindustrial subsistence patterns harbor high gut microbiome diversity that is not only higher than that seen in humans engaging in industrialized lifestyles but also higher compared to wild primates that typically consume fiber-rich diets

Phenotypic differentiation is associated with divergent sexual selection among closely related barn swallow populations

Albrecht, Tomas/0000-0002-9213-0034; Karaardic, Hakan/0000-0001-9839-4201; Hubbard, Joanna/0000-0002-7234-8001; Wilkins, Matthew/0000-0002-3162-6749WOS: 000389844700006PubMed: 27538265Sexual selection plays a key role in the diversification of numerous animal clades and may accelerate trait divergence during speciation. However, much of our understanding of this process comes from phylogenetic comparative studies, which rely on surrogate measures such as dimorphism that may not represent selection in wild populations. In this study, we assess sexual selection pressures for multiple male visual signals across four barn swallow (Hirundo rustica) populations. Our sample encompassed 2400 linear km and two described subspecies: European H. r. rustica (in the Czech Republic and Romania) and eastern Mediterranean H. r. transitiva (in Israel), as well as a potential area of contact (in Turkey). We demonstrate significant phenotypic differentiation in four sexual signalling axes, despite very low-level genomic divergence and no comparable divergence in an ecological trait. Moreover, the direction of phenotypic divergence is consistent with differences in sexual selection pressures among subspecies. Thus, H. r. transitiva, which have the darkest ventral plumage of any population, experience directional selection for darker plumage. Similarly, H. r. rustica, which have the longest tail feathers of any population, experience directional selection for elongated tail feathers and disruptive selection for ventral plumage saturation. These results suggest that sexual selection is the primary driver of phenotypic differentiation in this species. Our findings add to growing evidence of phenotypic divergence with gene flow. However, to our knowledge, this is the first study to relate direct measures of the strength and targets of sexual selection to phenotypic divergence among closely related wild populations.American Ornithologists' Union: Alexander Wetmore Research Award; CU EBIO Department; NSF Graduate Research Fellowship ProgramNational Science Foundation (NSF); National Science FoundationNational Science Foundation (NSF) [IOS-0717421, DEB-CAREER 1149942]; University of Colorado; Israel Science Foundation (ISF)Israel Science Foundation [1181/07]; Janos Bolyai Research Scholarship of the Hungarian Academy of SciencesHungarian Academy of Sciences; Ministry of Education, Youth and Sports of the Czech RepublicMinistry of Education, Youth & Sports - Czech Republic [LH14045]; American Museum of Natural History Frank M. Chapman Memorial FundField assistance was provided by Ozgun Eker and Leyla Kaplan in Turkey; Oldrich Tomasek, Romana Michalkova, Martina Soudkova, Natalie Prekopova, and Lucie Jancikova in the Czech Republic; Zoltan Benko and Gergely Osvath in Romania; and Yair Kopelma in Israel. We thank the Behavior Reading Group at UNL and two anonymous reviewers for helpful comments on the manuscript. This work was funded in part by an American Ornithologists' Union: Alexander Wetmore Research Award and graduate research funding from the CU EBIO Department (to MRW). MRW was supported by the NSF Graduate Research Fellowship Program. RJS was funded by the National Science Foundation (IOS-0717421 and DEB-CAREER 1149942) and the University of Colorado. Work in Israel was funded by the Israel Science Foundation (ISF grant number 1181/07 to Arnon Lotem). PLP was financed by the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences. Work in Turkey was conducted with permission of the General Directorate of Nature Conservation and National Parks. Work in the Czech Republic was funded by the Ministry of Education, Youth and Sports of the Czech Republic (project LH14045) (to TA), and by the American Museum of Natural History Frank M. Chapman Memorial Fund (to JKH)

Effects of habituation, research and ecotourism on faecal glucocorticoid metabolites in wild western lowland gorillas: Implications for conservation management

Wildlife tourism is proliferating worldwide and has the potential to raise revenue for conservation as well as public awareness of conservation issues. However, concerns are growing about the potentially negative influence of such tourism on the wildlife involved. We investigate the effects of habituation, ecotourism and research activities on levels of faecal glucocorticoid metabolites (FGCMs), a proxy for physiological stress, in wild western lowland gorillas (Gorilla gorilla gorilla) in the Central African Republic. We compare FGCMs in three human-contacted groups with those in unhabituated gorillas. We also explore how human–gorilla contact influences FGCMs of a gorilla group undergoing habituation and investigate how measures of general human–gorilla contact, tourism and human proximity influence FGCMs in recently and long-term habituated groups. Two of the three human-contacted groups had higher levels of FGCMs than unhabituated gorillas. The group undergoing habituation had the highest FGCMs, which increased up to 21 days following contacts, suggesting a cumulative FGCM response, in line with descriptions of a hormonal adaptation response to a chronic intermittent stressor. FGCMs in habituated groups were significantly associated with increasing frequency of violation of the 7 m distance rule by observers and with a medical intervention but not with other measures of human pressure. Our findings provide critical information for the management of this, and other, species whose conservation depends on habituation for ecotourism

Long-Term Monitoring of Microsporidia, Cryptosporidium and Giardia Infections in Western Lowland Gorillas (Gorilla gorilla gorilla) at Different Stages of Habituation in Dzanga Sangha Protected Areas, Central African Republic

Background Infectious diseases pose one of the greatest threats to endangered species, and a risk of gastrointestinal parasite transmission from humans to wildlife has always been considered as a major concern of tourism. Increased anthropogenic impact on primate populations may result in general changes in communities of their parasites, and also in a direct exchange of parasites between humans and primates. Aims To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, we conducted a long-term monitoring of microsporidia, Cryptosporidium and Giardia infections in western lowland gorillas at different stages of the habituation process, humans, and other wildlife in Dzanga-Sangha Protected Areas in the Central African Republic. Results We detected Encephalitozoon cuniculi genotypes I and II (7.5%), Enterocytozoon bieneusi genotype D and three novel genotypes (gorilla 1–3) (4.0%), Giardia intestinalis subgroup A II (2.0%) and Cryptosporidium bovis (0.5%) in gorillas, whereas in humans we found only G. intestinalis subgroup A II (2.1%). In other wild and domestic animals we recorded E. cuniculi genotypes I and II (2.1%), G. intestinalis assemblage E (0.5%) and C. muris TS03 (0.5%). Conclusion Due to the non-specificity of E. cuniculi genotypes we conclude that detection of the exact source of E. cuniculi infection is problematic. As Giardia intestinalis was recorded primarily in gorilla groups with closer human contact, we suggest that human-gorilla transmission has occurred. We call attention to a potentially negative impact of habituation on selected pathogens which might occur as a result of the more frequent presence of humans in the vicinity of both gorillas under habituation and habituated gorillas, rather than as a consequence of the close contact with humans, which might be a more traditional assumption. We encourage to observe the sections concerning hygiene from the IUCN best practice guidelines for all sites where increased human-gorilla contact occurs