Frontiers in Mammal Science最新文献

{"title":"Development and evaluation of an ensemble model to identify host-related metadata from fecal microbiota of zoo-housed mammals","authors":"Franziska Zoelzer, Daniel dos Santos Monteiro, P. Dierkes","doi":"10.3389/fmamm.2024.1380915","DOIUrl":"https://doi.org/10.3389/fmamm.2024.1380915","url":null,"abstract":"Much research has been conducted to describe the factors that determine the fecal microbiome, with diet and host phylogeny as the main drivers. The influence of diet has been described at different levels. Firstly, there are major differences in the microbiomes of herbivorous and carnivorous species and secondly the morphology of the digestive system also determines the composition and diversity of the microbiota. In this study, we aim to describe the influence of the three factors – diet, digestive system and host - on the microbiota in order to develop a model that is able to characterize host-specific metadata from an unknown fecal sample. We therefore analyzed the 16s rRNA from 525 fecal samples of 14 zoo-housed species belonging to different phylogenetic groups including herbivores, carnivores and omnivores. We found significant differences in the bacterial taxa correlated with these groups. While herbivores show positive correlations with a large number of bacterial taxa, we found fewer taxa correlating with carnivores or omnivores. We also detected considerable differences in the microbiota of the ruminant, hindgut fermenting and simple digestive system. Based on these results, we developed a logistic ensemble model, that predicts the diet and based on these findings either the herbivorous digestive system or the carnivorous host-family from a given fecal microbiota composition. This model is able to effectively discriminate herbivores, omnivores and carnivores. It also excels at predicting the herbivore-specific digestive system with 98% accuracy, further reinforcing the strong link between microbiota and digestive system morphology. Carnivorous host-family identification achieves an overall accuracy of 79%, although this performance varies between families. We provide this trained model as a tool to enable users to generate host-specific information from their microbiome data. In future research, tools such as the one presented here could lead to a combined approach of microbiome and host-specific analyses which would be a great advantage in non-invasive wildlife monitoring.","PeriodicalId":472266,"journal":{"name":"Frontiers in Mammal Science","volume":"28 s84","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141377832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expansion modes of primate nervous system structures in the light of the Prosomeric Model","authors":"Sara Ruiz-Cabrera, Isabel Pérez-Santos, Josefa Zaldivar-Diez, Miguel Ángel García-Cabezas","doi":"10.3389/fmamm.2023.1241573","DOIUrl":"https://doi.org/10.3389/fmamm.2023.1241573","url":null,"abstract":"The expansion of human and non-human primate central nervous system structures has been a paramount question for classic and contemporary studies in comparative vertebrate neuroanatomy. These studies can benefit from framing data analysis within the Prosomeric Model, which defines a common Bauplan for all vertebrate species, including mammals. According to this model, the vertebrate nervous system is composed of several Fundamental Morphological Units (FMUs) that are defined and delineated by characteristic gene expression profiles. Thus, the expansion of neural structures can be traced back to heterochronic neurogenesis, cell lineage specification, and axon growth in their corresponding FMUs. In the present article, we exemplify the use of the Prosomeric Model as the proper theoretical framework for analyzing the expansion of the cerebral and cerebellar cortices, the pontine nuclei, the striatum, the nigrostriatal dopaminergic system, the thalamus, and the amygdala in primates compared to rodents. We describe the quantitative (volume and neuron number) and qualitative (cytoarchitectonic and cell type differences) expansion of these structures in primates versus rodents and define different expansion modes. Then, we relate these modes to the developmental primary events of specification and secondary events of histogenesis, like neurogenesis. We conclude that the systematic analysis of the molecular regulation of primary and secondary developmental events in each FMU in rats, primates, and other mammals could provide the necessary insight to identify the causal mechanisms of the expansion modes described in the present article.","PeriodicalId":472266,"journal":{"name":"Frontiers in Mammal Science","volume":"359 18","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135393248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tool use, or not tool use, that is the question: is the necessity hypothesis really inconsequential for the African great apes?","authors":"Shelly Masi","doi":"10.3389/fmamm.2023.1281030","DOIUrl":"https://doi.org/10.3389/fmamm.2023.1281030","url":null,"abstract":"Investigating the drivers of tool use in animals has recently received great attention because of its implication in understanding animals’ cognition and the evolution of tool use in hominins. The necessity hypothesis posits tool use as a necessary response to food scarcity, but its role is an ongoing debate. The largest body of literature comparing animal tool use frequencies is with regard to primates, particularly comparisons between the Pan species. This supports the hypothesis that tool use is rarer in wild bonobos because of differential manipulation abilities of chimpanzees rather than different ecological needs. In this article, I aim to enrich the discussion concerning the necessity hypothesis and the ecological drivers of tool use in apes. The higher feeding flexibility of bonobos may be a key aspect to explaining the lower use of feeding tools than that observed in chimpanzees. The diet flexibility of bonobos is similar to that of the lowest level of tool users among the wild great apes: the gorilla. Gorillas can thus help to shed further light on this debate. When fruit is scarce, Western gorillas and bonobos rely more on widely available proteinaceous herbs than chimpanzees, who remain highly frugivorous. Chimpanzees may thus face a greater necessity to search for an alternative to obtain high-quality food: tool-assisted feeding. An indirect piece of evidence for this higher level of herbivory is that the prevalence of gut ciliates in bonobos is double that of chimpanzees. In each animal species, a different combination of necessity, opportunities, predisposition, and learning processes are likely to be at play in the emergence of flexible tool use in animals.","PeriodicalId":472266,"journal":{"name":"Frontiers in Mammal Science","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135093986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Von Economo neurons as a specialized neuron class of the human cerebral cortex","authors":"Zdravko Petanjek, Ivan Banovac, Dora Sedmak, Matija Vid Prkačin, Ana Hladnik","doi":"10.3389/fmamm.2023.1242289","DOIUrl":"https://doi.org/10.3389/fmamm.2023.1242289","url":null,"abstract":"By studying human cortical cytoarchitecture, von Economo noticed large spindle-shaped-neurons within layer Vb in the anterior-cingulate and fronto-insular cortex. Those neurons had such extremely elongated stick-like or corkscrew-like soma shape that appeared to him as a pathological alteration. Eventually, he realized that this was a specialized-type of neuron which he described as distinct from the main cortical cell populations, including the commonly found spindle cells. Data from recent studies suggest that specialized-stick-corkscrew-neurons may have first developed in the fronto-insular cortex before the division of hominids and Old World monkeys, and that they have become abundant in the anterior-cingulate cortex only in the hominid line. Golgi analysis found that they have distinctive somato-dendritic morphology with a characteristic very distal position of their axon origin. Many additional studies claimed to find cells similar to the specialized cells described by von Economo in other non-primate species, even in functionally unrelated cortical regions and layers. However, these studies did not provide sufficient evidence that the cells they described are indeed distinct from common spindle-shaped-neurons, and that they truly correspond to the specialized-stick-corkscrew-cells described by von Economo. We believe that present evidence primarily supports the presence of specialized-stick-corkscrew-neurons in hominids, with a seeming increase in their number in humans compared to other primates. The functional significance of such neuronal specialization within specific areas of the human cerebral cortex remains to be elucidated.","PeriodicalId":472266,"journal":{"name":"Frontiers in Mammal Science","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135590347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}