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51.
Diego F. Morales-Torres;Nelson Valdivia;Sara M. Rodríguez;Juan G. Navedo; 《Austral ecology》2024,49(1):e13298
Prey profitability is one of the most important factors influencing prey selection. This factor varies along with both prey size and handling time. Thus, large prey are generally highly profitable for consumers and boost competition. Kleptoparasitism is a form of competition in which an individual steals food previously obtained by another individual. Accordingly, handling large prey should increase the likelihood of kleptoparasitism occurrence, but these relationships remain poorly understood. Here, we studied kleptoparasitism occurrence by the Brown-Hooded Gull (Chroicocephalus maculipennis – Laridae) on Whimbrels (Numenius phaeopus hudsonicus – Scolopacidae) preying on intertidal Mole Crabs (Emerita analoga) in a wave-exposed sandy beach in southern Chile. Generalized linear models, fitted to data from focal-individual video sequences, showed that kleptoparasitism probability had a positive sigmoidal response to handling time. Moreover, with an increase of 1 s in handling time, a Whimbrel doubled its probability of being kleptoparasitized. Additionally, the odds of being kleptoparasitized were 17% higher with an increase of 10 mm in prey length and 47% higher with an increase of one gull per host. However, the effect of handling on kleptoparasitism probability slightly decreased (2%) with an increase of 10 mm in prey size class. Our results suggest the existence of a threshold time in which consumers can handle their prey before kleptoparasitism probability is too high. Nevertheless, Whimbrel's mean intake rate reached 0.15 ± 0.13 kJ s−1, allowing Whimbrels to theoretically meet their energetic requirements despite losing some prey to kleptoparasites. This study provides new insight into a common form of competition among consumers, highlighting the importance of prey handling time for shorebirds with a restricted foraging time driven by tidal cycles. 相似文献
52.
53.
Federico Morelli;Yanina Benedetti;Dilara Arslan;Juan Delgado; 《Oikos》2024,2024(11):e10785
We extensively reviewed scientific literature and extracted a large dataset with roadkill events for reptile species. We examined 300 articles from 33 European countries, gathering 1688 records of reptiles killed by vehicle traffic. A total of 125 taxa were found documented as roadkill (100 native and 25 exotic species). We calculated each species' occurrence frequency within the database (henceforth ‘relative roadkill frequency'). The relative roadkill of species was strongly and significantly correlated when comparing the whole dataset and the subset of systematic studies. We modelled the inter-specific variation in relative roadkill frequency across the European reptilian phylogeny concerning species traits, evolutionary uniqueness, and distribution range using a phylogenetic generalized least squares (PGLS) model. Overall, reptile casualties are more pronounced for more closely related species. However, the relative roadkill frequency was unrelated to the level of evolutionary distinctiveness of European reptiles. Additionally, relative roadkill frequency was not correlated to the distribution range but was positively correlated with the species' body mass. The reptiles more frequently cited as road casualties were overall relatively large species: Montpellier snake Malpolon monspessulanus, European grass snake Natrix natrix, and Caspian whipsnake Dolichophis caspius. Additionally, more active species during the crepuscular hours were less affected by roadkill. From a conservation point of view, our results suggest that roadkill frequency is not more significant for evolutionary, more unique reptiles than for other species in Europe, while at the same time, widely distributed species are not the main target of roadkill events. Then, the main causes of roadkill in reptiles must be associated with other factors, such as behavioural traits or density of populations, rather than simply the size of their distribution range. 相似文献
54.
Juan Li;Gabriela M. Ulloa;Pedro Mayor;Meddly L. Santolalla Robles;Alex D. Greenwood; 《Molecular ecology resources》2024,24(6):e13979
Collecting and preserving biological samples in the field, particularly in remote areas in tropical forests, prior to laboratory analysis is challenging. Blood samples in many cases are used for nucleic acid-based species determination, genomics or pathogen research. In most cases, maintaining a cold chain is impossible and samples remain at ambient temperature for extended periods of time before controlled storage conditions become available. Dried blood spot (DBS) storage, blood stored on cellulose-based paper, has been widely applied to facilitate sample collection and preservation in the field for decades. However, it is unclear how long-term storage on this substrate affects nucleic acid concentration and integrity. We analysed nucleic acid quality from DBS stored on Whatman filter paper no. 3 and FTA cards for up to 15 years in comparison to cold-chain stored samples using four nucleic acid extraction methods. We examined the ability to identify viral sequences from samples of 12 free-ranging primates in the Amazon forest, using targeted hybridization capture, and determined if mitochondrial genomes could be retrieved. The results suggest that even after extended periods of storage, DBS will be suitable for some genomic applications but may be of limited use for viral pathogen research, particularly RNA viruses. 相似文献
55.
Juan Zhu;Zhenzhen Liu;Feng Geng;Jing Peng;Zhimin Li;Qin Yang; 《Molecular Genetics & Genomic Medicine》2024,12(1):e2338
Developmental and epileptic encephalopathy 9 (DEE9) is characterized by early infantile seizures and mild-to-severe neuropsychiatric symptoms. Despite being an X-linked dominant disorder, DEE9 mainly affects heterozygous females or mosaic males, while hemizygous males are less affected. PCDH19 gene has been documented as the causative gene. 相似文献
56.
Juan Lin;Hongxia Wang;Jianfeng Chen;Yun Li; 《Molecular ecology》2024,33(21):e17528
Eutrophication reduces the variability of the community composition of plankton. However, the mechanisms underlying the diversity and restructuring of eukaryotic algal communities remain unknown. This study analysed the diversity and compositional patterns of algal communities in shallow eutrophic lakes. It investigated how these communities were modified by key genera through mediating inter-algal associations under the influence of abiotic factors. Inter-algal associations explained more variance in algal communities than environmental variables, and variation in composition and diversity was primarily derived from Scenedesmus, Desmodesmus and Cryptomonas, rather than nutrients. Scenedesmus and Desmodesmus were positively correlated with the genera of Chlorophyta and formed the hub of the algal association network. When the relative abundance of Scenedesmus and Desmodesmus increased from 0.41% to 13.74%, communities enriched in biomarkers of Bacillariophyta, Chrysophyceae and Cryptophyta transitioned to communities enriched in biomarkers of Chlorophyta. Moreover, negative associations between the Chlorophyta hub genera and other non-Chlorophyta genera increased. High concentrations of total phosphorus altered the composition of algal communities by increasing the abundance of Scenedesmus and Desmodesmus, which in turn had cascading effects through inter-algal associations. Additionally, algal communities with higher abundances of Scenedesmus and Desmodesmus were more susceptible to the effects of total phosphorus. Our study suggested that inter-algal associations, centred on Scenedesmus and Desmodesmus, had a greater influence on algal diversity and community structure than other factors. Nutrient levels were not a direct driver of algal diversity and community structure adjustments, but acted indirectly by enhancing the influence of Scenedesmus and Desmodesmus. 相似文献
57.
Kaijun Li;Liming Hou;Taoran Du;Guang Pu;Chenxi Liu;Gensheng Liu;Juan Zhou;Ruihua Huang;Qingbo Zhao;Pinghua Li; 《Animal genetics》2024,55(3):471-474
This work aimed to identify markers and candidate genes underlying porcine digestive traits. In total, 331 pigs were genotyped by 80 K Chip data or 50 K Chip data. For apparent neutral detergent fiber digestibility, a total of 19 and 21 candidate single nucleotide polymorphisms (SNP) were respectively identified using a genome-wide efficient mixed-model association algorithm and linkage-disequilibrium adjusted kinship. Among them, three quantitative trait locus (QTL) regions were identified. For apparent acid detergent fiber digestibility, a total of 16 and 17 SNPs were identified by these two methods, respectively. Of these, three QTL regions were also identified. Moreover, two candidate genes (MST1 and LATS1), which are functionally related to intestinal homeostasis and health, were detected near these significant SNPs. Taken together, our results could provide a basis for deeper research on digestive traits in pigs. 相似文献
58.
基于UPLC-QE-MS和16S rRNA基因测序技术分析溃疡性结肠炎（UC）小鼠肠道菌群及内源性代谢物之间的联动系统,挖掘关键生物标志物,探讨UC治疗的潜在靶点。
将雄性C57小鼠（体重18～22 g,8周龄）随机分为正常组与模型组,每组10只,模型组小鼠自由饮用2.5%葡聚糖硫酸钠诱导UC模型。记录小鼠体重变化率和DAI评分;测量结肠长度;HE染色和AB-PAS染色观察肠组织病理变化;ELISA法检测血清IL-1β与IL-10水平;非靶向代谢组学技术和16S rRNA基因测序技术联合分析小鼠内源性代谢物和肠道菌群的变化,挖掘潜在生物标志物。
与正常组比较,模型组小鼠体重变化率显著下降（
UC的发生发展伴随肠道菌群多样性下降与代谢紊乱。调节肠道菌群多样性、平衡氨基酸合成、甘油磷脂代谢和类花生酸代谢可能是诊疗UC的潜在靶点。
59.
Sohyeon Yun;Jun Ho Choi;Singeun Oh;Myungjun Kim;Myung-hee Yi;Dongjun Kang;Yun Soo Jang;In-Yong Lee;Tai-Soon Yong;Juan Kim;Heung Chul Kim;Jae Rok Lee;Ju Yeong Kim; 《Entomological Research》2024,54(4):e12727
Cockroaches are insects found in almost all habitats, including unsanitary environments. Understanding their microbial communities is crucial for assessing the potential risks they pose as vectors of pathogens. In this study, we assessed the microbial communities of omnivorous cockroaches collected from external environments and those reared in a clean laboratory for extended periods (5–20 years). Using the iSeq 100 system, we examined the relative abundance of microbial communities at the phylum, family and genus levels. Our results revealed that the predominant taxa in these cockroaches were Proteobacteria, Bacteroidetes and Firmicutes. Interestingly, the bacterial communities of samples from the same cockroach species, regardless of their living conditions, clustered together, indicating species-specific similarities in microbiomes. The symbiont genus Blattabacterium was consistently present in all samples, delivering nutrients to the host. Pathogen detection at the genus level indicated a higher prevalence of potential pathogens in cockroaches collected from field environments, compared with those from laboratory-reared cockroaches. These findings underscore the importance of cockroaches as pathogen reservoirs and vectors of opportunistic infections, emphasizing the need for further studies to identify specific microorganisms and confirm their pathogenicity. As cockroaches inhabit human environments, their potential to spread harmful bacteria through defecation warrants attention and underscores the significance of understanding their microbial ecology for public health implications. 相似文献
60.