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Zinner, D.

Publications and source records attributed to Zinner, D..

18 recordsLinked to original sources

Diversity and spatiotemporal activity patterns of medium and large mammals in the Niokolo-Koba National Park, Senegal

West African savannahs provide habitats to diverse species assemblages, yet remain understudied compared to their East and Southern African counterparts. The Niokolo-Koba National Park in southeastern Senegal constitutes one of the largest remaining protected areas in West Africa and supports a mosaic of savannah and forest habitats with a diverse assemblage of medium- and large-sized mammals. Here, we analysed camera-trap data originally collected to monitor predator presence in the northwestern sector of the National Park. We deployed 37 cameras across 37 km{superscript 2} from February 2022 to March 2023, resulting in 13,161 camera-trap-days. We assessed alpha diversity indices and spatiotemporal activity patterns of large and medium-sized mammals across habitat types. Evenness values - the degree to which species abundances are distributed uniformly within a community - were higher in the savannah than in forest habitats, although overall species richness was comparable. In contrast, animal sighting rates were higher in forests than in savannahs. Estimated diel activity mostly corresponded with established species-specific behavioural patterns. Our analyses revealed differential use of certain habitat types across the day, likely driven by spatially segregated sleeping sites and foraging locations. Our results provide a reference for future studies and monitoring efforts and highlight the value of the forest-savannah mosaic for the local species assemblage within the larger ecosystem of Niokolo-Koba National Park.

ecology↗

Nested Male Reproductive Strategies in a Tolerant Multilevel Primate Society

Male reproductive success varies within populations. Models explaining reproductive skew emphasise dominance, yet the determinants of male reproductive success in egalitarian societies remain poorly understood. Using nine years of behavioural and genetic data from five parties, we investigated male reproductive monopolisation in wild Guinea baboons (*Papio papio*), an egalitarian multilevel society with one-male "units" nested within "parties" and low male-male contest competition. Genetic analyses showed 93% of the 71 infants were sired by the female's "unit male", with extra-unit paternities consistent with limited control models. Reproduction was distributed among multiple unit males, resulting in low reproductive skew at the party level, with top males siring 23-40% of offspring, well below levels in despotic species. Female takeovers were rare, suggesting male restraint. Among prime-aged males, the number of unit females was only weakly positively associated with dominance ratings. Prime-age predicted reproductive success better than dominance. Non-prime-aged males had fewer females across dominance ratings. In conclusion, male Guinea baboons' reproductive potential is shaped less by dominance than by age and stable associations with females, who play an active role in inter-sexual relationships. These results emphasise the need to move beyond frameworks focused solely on dominance-based mechanisms and to consider species-specific social organisation.

animal behavior and cognition↗

Rapid updating of ecological information in wild Guinea baboons

Knowing where to find what kind of food when is essential for survival and reproduction. Recent links between feeding ecology and brain size have revived interest in foraging cognition as a core component in cognitive evolution. We investigated whether free-ranging Guinea baboons (Papio papio) keep track of the spatio-temporal availability of a preferred food resource, the Natal orange (Strychnos spinosa). A natural experiment, a massive wildfire that destroyed most oranges in 2019, allowed us to disentangle habitual routines from goal-directed behaviour in the baboons. The animals space-use patterns shifted significantly following the wildfire. After one single visit, they stopped going to the area during the period when Natal oranges would normally be available. In the following year, they resumed regular space-use patterns. We also assessed travel linearity, speed, and departure time from sleeping sites towards the target area with and without ripe fruit. Guinea baboons travelled more linearly, 14% faster, and ~40 minutes earlier towards the target area when S. spinosa was in season compared to when it was not. In conclusion, Guinea baboons rapidly updated their knowledge of high-value food availability and adjusted their space-use accordingly. These results underscore their capacity for flexible decision-making and goal-directed foraging.

animal behavior and cognition↗

Low genetic diversity in Colobus vellerosus populations in Kikele Sacred and Okuta Kobunan Forests, Benin

The critically endangered white-thighed colobus, Colobus vellerosus, is on the brink of extinction, necessitating the implementation of effective conservation management strategies. The population in Kikele village serves as the primary remaining stronghold for this species in Benin, comprising around twenty-eight individuals in the small Kikele Sacred Forest and an additional eight individuals in the community-managed Okuta Kobunan Forest. These two populations are believed to have descended from a single founding pair introduced to the Kikele region circa 1800. Given the small population size and the possible severe genetic bottleneck at its foundation, the genetic diversity might be extremely low. In our study, we conducted a first analysis of the genetic diversity of the two populations using mitochondrial markers, the complete cytochrome b (cytb) and a segment of the hypervariable control region (D-loop, 750 bp). Our findings revealed only one cytb haplotype, along with two haplotypes that differ by just one site in the D-loop. We recommend a range-wide population genetic assessment of the species to explore the possibility of translocations as a potential genetic rescue strategy.

genetics↗

Patterns of sleeping site use of Guinea baboon parties (Papio papio)

Sleeping site use in primates is thought to be influenced by multiple factors, including resource availability and competition, predation risk, and the risk of parasitic infection. While previous research has highlighted the importance of these factors, few studies have examined sleeping site use among multiple groups of non-territorial species with overlapping home ranges. Here, we investigated the sleeping site use of Guinea baboons (Papio papio) in Simenti, Senegal. We used locational data for four years of several baboon parties sharing the same range. We assessed the distribution of sleeping sites within the local habitat mosaic, the proximity of sleeping sites to those of co-occurring parties and the impact of food availability and predator presence at the landscape level on the distance between parties sleeping sites on the same night. We further investigated patterns of sleeping site use of parties across time. We found that the vast majority of sleeping sites were in the gallery forest along the perennial Gambia River, likely due to the availability of tall trees. Guinea baboons slept in close spatial proximity (>50m) to at least one other party regardless of food availability and predator presence. Patterns of sleeping site use showed no evidence of predator or parasite avoidance. Thus, Guinea baboons in Simenti likely use the abundantly available sleeping sites opportunistically rather than being driven by intergroup competition or strategies for predator avoidance or reduction of the risk of parasite infection.

ecology↗

Patterns of landscape partitioning indicate low levels of resource competition among neighbouring Guinea baboon(Papio papio) parties

BackgroundAccess to critical resources, including food, water, or shelter, significantly determines individual fitness. As these resources are limited in most habitats, animals may employ strategies of landscape partitioning to mitigate the impact of direct resource competition. Territoriality may be regarded as an aggressive form of landscape partitioning but in non-territorial species, other forms exist. Animals living in groups with greater flexibility in their association patterns, such as multilevel societies with fission-fusion dynamics, may adjust their grouping and space use patterns to short-term variations in ecological conditions such as food availability, predation pressure, or the presence of conspecific groups. This flexibility may allow them to balance the costs of competition while reaping the benefits of better predator detection and defence. MethodsWe explored patterns of landscape partitioning among neighbouring Guinea baboon (Papio papio) parties in the Niokolo-Koba National Park, Senegal. Guinea baboons live in a multilevel society in which parties predictably form higher-level associations ("gangs"). We used four years of locational data from individuals equipped with GPS collars to estimate annual home ranges, home range overlap, and minimum distances between parties. We examined whether food availability and predator presence levels affected the cohesion between parties in 2022. ResultsWe found substantial home range and core area overlap among parties (33 to 100%). We found no effect of food availability or predator presence on the distance to the closest neighbouring party; the minimum distance between parties was less than 100 m on average. ConclusionsOur results suggest a low level of feeding competition between our study parties. Whether this is a general feature of Guinea baboons or particular to the situation in the Niokolo-Koba National Park remains to be investigated.

ecology↗

African bush pigs exhibit porous species boundaries and appeared in Madagascar concurrently with human arrival

Several African mammals exhibit a phylogeographic pattern where closely related taxa are split between West/Central and East/Southern Africa, but their evolutionary relationships and histories remain controversial. Bushpigs (Potamochoerus larvatus) and red river hogs (P. porcus) are recognised as separate species due to morphological distinctions, a perceived lack of interbreeding at contact, and putatively old divergence times, but historically, they were considered conspecific. Moreover, the presence of Malagasy bushpigs as the sole large terrestrial mammal shared with the African mainland raises intriguing questions about its origin and arrival in Madagascar. Analyses of 67 whole genomes revealed a genetic continuum between the two species, with putative signatures of historical gene flow, variable FST values, and a recent divergence time (<500,000 years). Thus, our study challenges key arguments for splitting Potamochoerus into two species and suggests their speciation might be incomplete. Our findings also indicate that Malagasy bushpigs diverged from southern African populations and underwent a limited bottleneck 1,000-5,000 years ago, concurrent with human arrival in Madagascar. These results shed new light on the evolutionary history of an iconic and widespread African genus and provide insight into the longstanding biogeographic puzzle surrounding the bushpigs presence in Madagascar.

evolutionary biology↗

Distribution and extent of suitable habitat for geladas (Theropithecus gelada) in the Anthropocene

BackgroundClimate change coupled with other anthropogenic pressures may affect species distributions, often causing extinctions at different scales. This is particularly true for species occupying marginal habitats such as gelada, Theropithecus gelada. Our study aimed to model the impact of climate change on the distribution of suitable habitats for geladas and draw conservation implications. Our modelling was based on 285 presence locations of geladas, covering their complete current distribution. We used different techniques to generate pseudoabsence datasets, MaxEnt model complexities, and cut-off thresholds to map the potential distribution of gelada under current and future climates (2050 and 2070). We assembled maps from these techniques to produce a final composite map. We also evaluated the change in the topographic features of gelada over the past 200 years by comparing the topography in current and historical settings. ResultsAll model runs had high performances, AUC = 0.87 - 0.96. Under the current climate, the suitable habitat predicted with high certainty was 90,891 km2, but it decreased remarkably under future climates, -36% by 2050 and -52% by 2070. Whereas no remarkable range shift was predicted under future climates, currently geladas are confined to higher altitudes and complex landscapes compared to historical sightings, probably qualifying geladas as refugee species. ConclusionsOur findings indicated that climate change most likely results in a loss of suitable habitat for geladas, particularly south of the Rift Valley. The difference in topography between current and historical sightings is potentially associated with anthropogenic pressures that drove niche truncation to higher altitudes, undermining the climatic and topographic niche our models predicted. We recommend protecting the current habitats of geladas even when they are forecasted to become climatically unsuitable in the future, in particular for the population south of the Rift Valley.

ecology↗

Genome-wide coancestry reveals details of ancient and recent male-driven reticulation in baboons

Baboons (genus Papio) are a morphologically and behaviorally diverse clade of catarrhine monkeys that have experienced hybridization between phenotypically and genetically distinct phylogenetic species. We used high coverage whole genome sequences from 225 wild baboons representing 19 geographic localities to investigate population genomics and inter-species gene flow. Our analyses provide an expanded picture of evolutionary reticulation among species and reveal novel patterns of population structure within and among species, including differential admixture among conspecific populations. We describe the first example of a baboon population with a genetic composition that is derived from three distinct lineages. The results reveal processes, both ancient and recent, that produced the observed mismatch between phylogenetic relationships based on matrilineal, patrilineal, and biparental inheritance. We also identified several candidate genes that may contribute to species-specific phenotypes. One-Sentence SummaryGenomic data for 225 baboons reveal novel sites of inter-species gene flow and local effects due to differences in admixture.

evolutionary biology↗

Not one, but multiple radiations underlie the biodiversity of Madagascar's endangered lemurs

Lemurs are often cited as an example of adaptive radiation. Since colonizing Madagascar, more than 100 extant lemur species have evolved to fill a variety of ecological niches on the island. However, recent work suggests that lemurs do not exhibit one of the hallmarks of other adaptive radiations: explosive speciation rates that decline over time. Thus, characterizing the tempo and mode of evolution in lemurs can help us understand alternative ways that hyperdiverse clades arise over time, which might differ from traditional models. We explore the evolution of lemurs using a phylogenomic dataset with broad taxonomic sampling that includes the lemurs sister group, the lorisiforms of Asia and continental Africa. Our analyses reveal multiple bursts of diversification (without subsequent declines) that explain much of todays lemur diversity. We also find higher rates of speciation in Madagascars lemurs compared to lorisiforms, and we demonstrate that the lemur clades with exceptionally high diversification rates have higher rates of genomic introgression. This suggests that hybridization in these primates is not an evolutionary dead-end, but a driving force for diversification. Considering the conservation crisis affecting strepsirrhine primates, with approximately 95% of species being threatened with extinction, this phylogenomic study offers a new perspective for explaining Madagascars exceptional primate diversity and reveals patterns of speciation, extinction, and gene flow that will help inform future conservation decisions.

evolutionary biology↗

Adulis and the transshipment of baboons during classical antiquity

Adulis, located on the Red Sea coast in present-day Eritrea, was a bustling trading centre between the first and seventh centuries CE. Several classical geographers--Agatharchides of Cnidus, Pliny the Elder, Strabo--noted the value of Adulis to Greco-Roman Egypt, particularly as an emporium for living animals, including baboons (Papio spp.). Though fragmentary, these accounts predict the Adulite origins of mummified baboons in Ptolemaic catacombs, while inviting questions on the geoprovenance of older (Late Period) baboons recovered from Gabbanat el-Qurud ("Valley of the Monkeys"), Egypt. Dated to ca. 800-540 BCE, these animals could extend the antiquity of Egyptian-Adulite trade by as much as five centuries. To explore this possibility, we analysed complete mitochondrial genomes from a mummified baboon from Gabbanat el-Qurud and 14 museum specimens with known provenance together with published georeferenced mitochondrial sequence data. Phylogenetic assignment connects the mummified baboon to modern populations of Papio hamadryas in Eritrea and eastern Sudan. This result, assuming geographical stability of phylogenetic clades, suggests that present-day Eritrea, and by extension Adulis, was a source of baboons for Late Period Egyptians. It also establishes geographic continuity with baboons from the fabled Land of Punt (Dominy et al., 2020), giving weight to speculation that Punt and Adulis were essentially the same trading centres separated by a thousand years of history.

zoology↗

Male Guinea baboon tracking of female whereabouts

In group-living species, evolution puts a premium on the ability of individuals to track the state, whereabouts, and interactions of others. The value of social information might vary with the degree of competition within and between groups, however. We investigated male monitoring of female location in wild Guinea baboons (Papio papio). Guinea baboons live in socially tolerant multi-level societies with one-male-units comprising 1-6 females and young at the core. Using field playback experiments, we first tested whether male Guinea baboons (N=14) responded more strongly to playbacks of associated vs. non-associated females, which was the case. In the second and core experiment, we tested whether males (N=22 males, N=62 trials) keep track of the whereabouts of associated females by playing back unit females calls from locations that were either consistent or inconsistent with the actual position of the female. Contrary to predictions, males responded equally strongly in both conditions. While males seem to recognize their females by voice, they might lack the attention or motivation to track their females movement patterns. These results reinforce the view that the value of social information may vary substantially with the distribution of power in a society. While highly competitive regimes necessitate high attention to deviations from expected patterns, egalitarian societies allow for a certain degree of obliviousness.

animal behavior and cognition↗

MALE-MALE SOCIAL BONDING, COALITIONARY SUPPORT AND REPRODUCTIVE SUCCESS IN WILD GUINEA BABOONS

Male-male bonds may confer substantial fitness benefits. The adaptive value of these relationships is often attributed to coalitionary support, which aids in rank ascension and female defence, ultimately resulting in greater reproductive success. We investigated the link between male-male sociality and both coalitionary support and reproductive success in wild Guinea baboons. This species lives in a tolerant multi-level society with reproductive units comprising a male and 1-6 females at the core. Males are philopatric, form differentiated, stable, and equitable affiliative relationships ( strong bonds) with other males, and lack a clear rank hierarchy. Here, we analysed behavioural and paternity data for 30 males and 50 infants collected over four years in the Niokolo-Koba National Park, Senegal. Strongly bonded males supported each other more frequently during conflicts, but strong bonds did not promote reproductive success. Instead, males that spent less time socializing with other males were associated with a higher number of females and sired more offspring. Notably, reproductively active males still maintained bonds with other males, but adjusted their social investment in relation to life-history stage. Long-term data will be needed to test if the adaptive value of male bonding lies in longer male tenure and/or in promoting group cohesion.

animal behavior and cognition↗

Genomic Skimming and Nanopore Sequencing Uncover Cryptic Hybridization in One of World's Most Threatened Primates

The Brazilian buffy-tufted-ear marmoset (Callithrix aurita), one of the worlds most endangered primates, is threatened by anthropogenic hybridization with exotic, invasive marmoset species. As there are few genetic data available for C. aurita, we developed a PCR-free protocol with minimal technical requirements to rapidly generate genomic data with genomic skimming and portable nanopore sequencing. With this direct DNA sequencing approach, we successfully determined the complete mitogenome of a marmoset that we initially identified as C. aurita. The obtained nanopore-assembled sequence was highly concordant with a Sanger sequenced version of the same mitogenome. Phylogenetic analyses unexpectedly revealed that our specimen was a cryptic hybrid, with a C. aurita phenotype and C. penicillata mitogenome lineage. We also used publicly available mitogenome data to determine diversity estimates for C. aurita and three other marmoset species. Mitogenomics holds great potential to address deficiencies in genomic data for endangered, non-model species such as C. aurita. However, we discuss why mitogenomic approaches should be used in conjunction with other data for marmoset species identification. Finally, we discuss the utility and implications of our results and genomic skimming/nanopore approach for conservation and evolutionary studies of C. aurita and other marmosets.

evolutionary biology↗

Variation in predicted COVID-19 risk among lemurs and lorises

The novel coronavirus SARS-CoV-2, which in humans leads to the disease COVID-19, has caused global disruption and more than 1.5 million fatalities since it first emerged in late 2019. As we write, infection rates are currently at their highest point globally and are rising extremely rapidly in some areas due to more infectious variants. The primary viral target is the cellular receptor angiotensin-converting enzyme-2 (ACE2). Recent sequence analyses of the ACE2 gene predicts that many nonhuman primates are also likely to be highly susceptible to infection. However, the anticipated risk is not equal across the Order. Furthermore, some taxonomic groups show high ACE2 amino acid conservation, while others exhibit high variability at this locus. As an example of the latter, analyses of strepsirrhine primate ACE2 sequences to date indicate large variation among lemurs and lorises compared to other primate clades despite low sampling effort. Here, we report ACE2 gene and protein sequences for 71 individual strepsirrhines, spanning 51 species and 19 genera. Our study reinforces previous results and finds additional variability in other strepsirrhine species, and suggests several clades of lemurs have high potential susceptibility to SARS-CoV-2 infection. Troublingly, some species, including the rare and Endangered aye-aye (Daubentonia madagascariensis), as well as those in the genera Avahi and Propithecus, may be at high risk. Given that lemurs are endemic to Madagascar and among the primates at highest risk of extinction globally, further understanding of the potential threat of COVID-19 to their health should be a conservation priority. All feasible actions should be taken to limit their exposure to SARS-CoV-2.

genetics↗

Mitogenomic Phylogeny of Callithrix with Special Focus on Human Transferred Taxa

Callithrix marmosets are a relatively young primate radiation, whose phylogeny is not yet fully resolved. These primates are naturally para- and allopatric, but three species with highly invasive potential have been introduced into the southeastern Brazilian Atlantic Forest by the pet trade. There, these species hybridize with each other and endangered, native congeners. We aimed here to reconstruct a robust Callithrix phylogeny and divergence time estimates, and identify the biogeographic origins of autochthonous and allochthonous Callithrix mitogenome lineages. We sequenced 49 mitogenomes from four species (C. aurita, C. geoffroyi, C. jacchus, C. penicillata) and anthropogenic hybrids (C. aurita x Callithrix sp., C. penicillata x C. jacchus, Callithrix sp. x Callithrix sp., C. penicillata x C. geoffroyi) via Sanger and whole genome sequencing. We combined these data with previously published Callithrix mitogenomes to analyze five Callithrix species in total. ResultsWe report the complete sequence and organization of the C. aurita mitogenome. Phylogenetic analyses showed that C. aurita was the first to diverge within Callithrix 3.54 million years ago (Ma), while C. jacchus and C. penicillata lineages diverged most recently 0.5 Ma as sister clades. MtDNA clades of C. aurita, C. geoffroyi, and C. penicillata show intraspecific geographic structure, but C. penicillata clades appear polyphyletic. Hybrids, which were identified by phenotype, possessed mainly C. penicillata or C. jacchus mtDNA haplotypes. The biogeographic origins of mtDNA haplotypes from hybrid and allochthonous Callithrix were broadly distributed across natural Callithrix ranges. Our phylogenetic results also evidence introgression of C. jacchus mtDNA into C. aurita. ConclusionOur robust Callithrix mitogenome phylogeny shows C. aurita lineages as basal and C. jacchus lineages among the most recent within Callithrix. We provide the first evidence that parental mtDNA lineages of anthropogenic hybrid and allochthonous marmosets are broadly distributed inside and outside of the Atlantic Forest. We also show evidence of cryptic hybridization between allochthonous Callithrix and autochthonous C. aurita. Our results encouragingly show that further development of genomic resources will allow to more clearly elucidate Callithrix evolutionary relationships and understand the dynamics of Callithrix anthropogenic introductions into the Brazilian Atlantic Forest.

genomics↗

Post-copulatory behavior of olive baboons (Papio anubis) infected by Treponema pallidum

In nonhuman primates pathogens are known to exert a profound and pervasive cost on various aspects of their sociality and reproduction. In olive baboons (Papio anubis) at Lake Manyara National Park, genital skin ulcers caused by Treponema pallidum subsp. pertenue lead to mating avoidance in females and altered mating patterns at a pre-copulatory and copulatory level. Beyond this level, sexual behavior comprises also post-copulatory interactions among the sexual partners. To investigate whether the presence of genital skin ulcers has an impact at the post-copulatory level, we analyzed 517 copulation events of 32 cycling females and 29 males. The occurrence of post-copulatory behaviors (i.e., copulation calls, darting [female rapid withdraw from the male] and post-copulatory grooming) was not altered by the presence of genital skin ulcerations. Similarly to other baboon populations, females of our group were more likely to utter copulation calls after ejaculatory copulation. The likelihood of darting was higher after ejaculatory copulations and with the presence of copulation calls. Post-copulatory grooming was rarely observed but when it occurred, males groomed females for longer periods when females uttered copulation calls during, or preceding mating. Our results indicate that despite the presence of conspicuous genital skin ulcers, the post-copulatory behavior was not affected by the genital health status of the dyad. This suggests that infection cues play a major role before and during mating but do not affect post-copulatory behavior.

animal behavior and cognition↗

Coordination during group departures and group progressions in the tolerant multilevel society of wild Guinea baboons (Papio papio)

ObjectivesMost primate species live in groups, and temporal and spatial coordination of activities of individuals is essential for maintaining group cohesion, and there is still considerable debate to which degree social organization, the extent of despotism, and resource distribution shape group coordination processes. As different baboon species exhibit considerable variation in all of these factors, they constitute an excellent test case to resolve this debate.\n\nMaterials and MethodsWe analyzed group departures and progressions of Guinea baboons, Papio papio, in the Niokolo Koba National Park in Senegal. Guinea baboons live in a multi-level society with strong male bonds and a lack of a clear dominance hierarchy between males.\n\nResultsTwo-thirds of departures were initiated by adult males, and one third by adult females. Although initiators were more likely to signal than followers, signaling did not affect the initiation success. During group progression, males that were not affiliated with females were predominantly found in the front, while affiliated males, females and young were observed more frequently closer to the center of the group, and no preferences for rear positions. Overall, affiliated subjects were more likely to depart and travel together.\n\nDiscussionThe group departures in Guinea baboons differed strikingly from the elaborate negotiation behaviors among male hamadryas baboons, Papio hamadryas. We did not observe that specific individuals dominated the group coordination. Neither social organization, variation in despotism, nor resource distribution alone explain variation between species. Future studies should test whether specific combinations of factors promote the occurrence of negotiation processes.\n\nResearch HighlightsO_LIIn wild Guinea baboons, both adult males and females initiated group departures\nC_LIO_LIInitiators signaled during departures, but this did not affect initiation success\nC_LIO_LISolitary males were predominantly found at the front during group progression\nC_LI

animal behavior and cognition↗