Herbivore Feces Research Articles

Associations between intestinal lactic acid bacteria species and feeding habits of zoo animals.

Aim: Lactic acid bacteria are among the most important bacteria in the intestinal flora and often have beneficial effects on the host. It is known that the bacteria that compose the intestinal flora are influenced by the feeding habits of host animals, but there was a lack of knowledge about lactic acid bacteria. Therefore, also considering the use of select strains as probiotics, this study investigated the relationship between the feeding habits of zoo animals and intestinal Lactobacillaceae species. Methods: Lactic acid bacteria belonging to the family Lactobacillaceae were isolated and identified from the feces of 20 zoo animal species (5 carnivores, 4 herbivores, 7 piscivores, and 4 omnivores). Isolates were identified by the homology of the 16S rRNA gene sequence. In addition, the fecal flora of host animals was evaluated by the 16S rRNA gene amplicon sequencing. Results: The types of Lactobacillaceae species were shown to vary depending on the feeding habits of host animals. Ligilactobacillus salivarius (L. salivarius) and Ligilactobacillus saerimneri (L. saerimneri) were isolated from the feces of carnivores. Whereas Ligilactobacillus equi (L. equi), Limosilactobacillus gorillae, Ligilactobacillus hayakitensis and L. salivarius were isolated from the feces of herbivores. These Lactobacillaceae species were not found in the feces of piscivores. Instead, Enterococcus were frequently found in piscivores. The fecal flora also differed according to the feeding habits of host animals; at the phylum level, Bacillota was predominant in all animals; on the other hand, herbivores tended to have a higher proportion of Bacteroidota than carnivores, and piscivores tended to have a higher proportion of Proteobacteria. Conclusion: Lactic acid bacteria differ among animal species in a manner dependent on the hosts' feeding habits.

Fecal DNA analysis coupled with the sighting records re-expanded a known distribution of dugongs in Ryukyu Islands after half a century

DNA analysis of large herbivore feces samples collected from seagrass beds at two distant sites (Irabu Island in Miyako Islands and Kushi in Okinawa Island) in the Ryukyu Islands proved that some of these feces were from dugongs, which had been treated in recent studies as extinct in this region since the last stranding of a deceased individual in 2019. In addition, local knowledge of sightings of animals thought to be dugongs and confirmed cases of dugong feeding trails since 2010 were compiled to estimate its recent distribution. This is the first scientific report on the presence of this mammal in the Ryukyu Islands within the last four years, and particularly in the Miyako Islands within the last half-century. As the Ryukyu Islands are known to be the northern limit of the dugong’s fragmented distribution in East Asia, conservation efforts are therefore needed.

Targeted Screening of Fiber Degrading Bacteria with Probiotic Function in Herbivore Feces.

Cellulolytic bacteria with probiotic functions play a crucial role in promoting the intestinal health in herbivores. In this study, we aimed to correlate the 16S rRNA gene amplicon sequencing and fiber-degrading enzyme activity data from six different herbivore feces samples. By utilizing the separation and screening steps of probiotics, we targeted and screened high-efficiency fiber-degrading bacteria with probiotic functions. The animals included Maiwa Yak (MY), Holstein cow (CC), Tibetan sheep (TS), Southern Sichuan black goat (SG), Sichuan white rex rabbit (CR), and New Zealand white rabbit (ZR). The results showed that the enzymes associated with fiber degradation were higher in goat and sheep feces compared to cattle and rabbit's feces. Correlation analysis revealed that Bacillus and Fibrobacter were positively correlated with five types of fiber-degrading related enzymes. Notably, the relative abundance of Bacillus in the feces of Tibetan sheep was significantly higher than that of other five herbivores. A strain TS5 with good cellulose decomposition ability from the feces of Tibetan sheep by Congored staining, filter paper decomposition test, and enzyme activity determination was isolated. The strain was identified as Bacillus velezensis by biological characteristics, biochemical analysis, and 16S rRNA gene sequencing. To test the probiotic properties of Bacillus velezensis TS5, we evaluated its tolerance to acid and bile salt, production of digestive enzymes, antioxidants, antibacterial activity, and adhesion ability. The results showed that the strain had good tolerance to pH 2.0 and 0.3% bile salts, as well as good potential to produce cellulase, protease, amylase, and lipase. This strain also had good antioxidant capacity and the ability to antagonistic Staphylococcus aureus BJ216, Salmonella SC06, Enterotoxigenic Escherichia coli CVCC196, and Escherichia coli ATCC25922. More importantly, the strain had good self-aggregation and Caco-2 cell adhesion rate. In addition, we tested the safety of Bacillus velezensis TS5 by hemolysis test, antimicrobial susceptibility test, and acute toxicity test in mice. The results showed that the strain had no hemolytic phenotype, did not develop resistance to 19 commonly used antibiotics, had no cytotoxicity to Caco-2, and did not have acute toxic harm to mice. In summary, this study targeted isolated and screened a strain of Bacillus velezensis TS5 with high fiber-degrading ability and probiotic potency. This strain can be used as a potential probiotic for feeding microbial preparations for ruminants.

Herbivores influence biogeochemical processes by altering litter quality and quantity in a subarctic wetland

Global change drivers that modify the quality and quantity of litter inputs to soil affect greenhouse gas fluxes, and thereby constitute a feedback to climate change. Carbon cycling in the Yukon–Kuskokwim (Y–K) River Delta, a subarctic wetland system, is influenced by landscape variations in litter quality and quantity generated by herbivores (migratory birds) that create ‘grazing lawns’ of short stature, nitrogen-rich vegetation. To identify the mechanisms by which these changes in litter inputs affect soil carbon balance, we independently manipulated qualities and quantities of litter representative of levels found in the Y–K Delta in a fully factorial microcosm experiment. We measured CO2 fluxes from these microcosms weekly. To help us identify how litter inputs influenced greenhouse gas fluxes, we sequenced soil fungal and bacterial communities, and measured soil microbial biomass carbon, dissolved carbon, inorganic nitrogen, and enzyme activity. We found that positive correlations between litter input quantity and CO2 flux were dependent upon litter type, due to differences in litter stoichiometry and changes to the structure of decomposer communities, especially the soil fungi. These community shifts were particularly pronounced when litter was added in the form of herbivore feces, and in litter input treatments that induced nitrogen limitation (i.e., senesced litter). The sensitivity of carbon cycling to litter quality and quantity in this system demonstrates that herbivores can strongly impact greenhouse gas fluxes through their influence on plant growth and tissue chemistry.Graphical abstract

Short Communication: Morphological, biochemical, and molecular identification of cellulolytic bacteria isolated from feces of endemic tropical herbivores

Abstract. Suharti S, Novrariani N, Wiryawan KG. 2023. Short Communication: Morphological, biochemical, and molecular identification of cellulolytic bacteria isolated from feces of endemic tropical herbivores. Biodiversitas 24: 4046-4051. Indonesia has endemic herbivores that consume lignocellulose feedstuffs including grass, tree foliage, rice straw, and legume, indicating the presence of cellulolytic bacteria in their gastrointestinal tracts. Therefore, the aim of this study was to isolate and identify cellulolytic bacteria from the feces of tropical endemic herbivores, including anoa (Bubalus depressicornis), banteng (Bos javanicus), muntjak (Muntiacus muntjak), and timor deer (Rusa timorensis). Bacteria were isolated using the serial dilution technique and screened on Carboxy Methyl Cellulose (CMC) media. The selected isolates were identified based on their morphological and biochemical characteristics, cellulase enzyme activity, and molecular identification of 16S rDNA. The result showed that a total of five bacterial isolates were isolated from feces of anoa, banteng, muntjak, and timor deer. In addition, isolates exhibited characteristics of facultative anaerobes with gram-positive coccus, fermenting glucose, fructose, sucrose, starch, and cellulose. Based on cellulolytic index, isolates from anoa and banteng feces showed high cellulolytic activity with an index of about 1.2, indicating their potential as cellulose-degrading bacteria. Molecular identification and phylogeny analysis of cellulolytic bacteria isolates from anoa and banteng feces showed 100% similarities with Enterococcus faecium. Therefore, bacteria from feces of tropical endemic herbivores, especially anoa and banteng, possess cellulolytic activity and have potential as cellulolytic probiotic for ruminants that feed on forage-based diet. This is the first study to document the cellulolytic activity of anoa, and banteng feces.

Pentose-Fermenting Yeasts in Nature: Ecology, Biodiversity and Applications

The world’s energy sector has undergone drastic changes in the last decades due to the climate change and the turn to renewable energy sources. Biomass is the largest renewable source of carbohydrates on the Earth and is an important substrate for biofuel production. Saccharomyces cerevisiae yeasts are the main producer of first-generation ethanol from corn and sugarcane. However, these yeasts lack the ability to utilize the important components of lignocelluloses such as pentoses D-xylose and L-arabinose. Pentose-fermenting yeasts could become an alternative to S. cerevisiae in ethanol production from lignocelluloses. This review focuses on the ecology, geographical distribution, taxonomy, and potential applications of naturally-occurring pentose-fermenting yeasts. Pentose-fermenting yeasts have been frequently found in the lignocelluloseassociated substrates. Decaying and rotten wood and the gut of wood-boring insects are especially important natural reservoirs of this group of yeasts. Simple sugars xylose and L-arabinose would be present in such habitats as suitable nutrients for pentose-assimilating yeasts. The other natural habitats reported for pentose-fermenting yeasts are soil, plants, and herbivore faeces. Pentose-fermenting yeasts are found in many geographical regions and have been isolated on almost each continent. Dozens of novel pentose-fermenting yeast species have been discovered in the last decade. The previously poorly explored regions, including Brazil, China, and several Asian countries were especially oft en reported as sites of isolation of such yeasts. Most xylose-fermenting yeasts belong to genera Scheffersomyces, Candida, Spathaspora, Sugiyamaella, and Pachysolen, while the most efficient ethanol producers are represented by species Scheffersomyces stipitis and Spathaspora passalidarum. The vast majority of research on the biotechnological application of pentose-fermenting yeasts focuses on their role in the production of bioethanol from lignocellulose. This group of yeasts could be either directly involved in the fermentation stage of ethanol production or serve as a source of genetic material for the genetic manipulation of other industrial yeast strains. Pentose-fermenting yeasts could also be involved in the production of various chemicals from lignocellulosic substrates, mainly polyols, xylitol, and arabitol. Thus, the search for novel pentose-fermenting yeasts that could become new efficient ethanol producers or donors of new genetic material is still ongoing. The previously unexplored or poorly studied geographical regions and natural habitats can hide many novel yeasts with huge biotechnological potential.

Effects of Inhabiting and Life Patterns on the UV Spectral Properties of Small Mammalian Herbivores’ Urine

It is well known that avian predators can use prey excretions such as urine and feces to track their prey, and the urine and feces of small mammalian herbivores can reflect ultraviolet (UV) light and emit fluorescent light. There are still some debates as to whether UV visibility of small mammalian herbivores’ urine is used as a hunting cue by avian raptors. Some studies in Europe have demonstrated that diurnal raptors are capable of utilizing these cues to target key prey species. However, researchers in Australia have argued that raptors do not use the UV visibility of urine while hunting. To our knowledge, there are no reports from Asia concerning the ultraviolet spectral characteristics of small mammal herbivores’ urine. This study examined the UV spectral properties of urine from 6 small mammal herbivores species by comparing the UV reflectance and fluorescence spectra of urine from small mammalian herbivores living in plateau meadows, plateau shrubs, open marshland, farmland, and semi-desert grassland in China. In addition, we compared the UV spectral properties of urine from ground-dwelling species of rodents and subterranean species to determine whether ultraviolet visibility of small mammal herbivores’ urine could be used as a visual signal by Asian vole-eating raptors. The results showed that: 1) the SC370 values of urine from four small mammal herbivores species were ordered as plateau pika (plateau meadow) > root voles (plateau bush) > reed voles (swampland) > Brandt’s vole (desert grassland); and 2) UV fluorescence peak intensity and the wavelengths of urine from ground-dwelling species (such as the root vole, plateau pika, or Brandt’s vole) were significantly higher than those of subterranean-dwelling species (mandarin vole and plateau zokor). These results indicate that UV visibility of small mammal herbivores’ urine may act as a visual cue for raptors.

Attractiveness of dung beetles (Coleoptera: Scarabaeinae) to faeces from native mammals in different trophic guilds

AbstractDung beetles are predominantly coprophagous and use mammalian faeces as their main food resource and for offspring rearing. However, these resources are generally ephemeral and scarce. The objective of this study was to verify the attractiveness to dung beetles of the faeces of nine native mammal species of the Cerrado biome in different trophic guilds. This study was conducted during the rainy season (October 2016 to March 2017) in two sensu stricto areas of the Cerrado in the Brasília National Park (PNB), Federal District, Brazil. Pitfalls containing faeces of nine mammals native to the region were used as bait (from three herbivores, three carnivores and three omnivores) for the collection of dung beetles. We collected 203 individuals and 19 species, and the most abundant species were Uroxys aff. thoracalis, Oxysternon palemo, Coprophanaeus spitzi and Diabroctis mirabilis. The most attractive faecal bait was from the omnivorous Chrysocyon brachyurus (32.67% of the individuals and 13 species). This study reveals variation in the attraction of dung beetles to native mammal dung of the Cerrado, with more abundance in the faeces of omnivores and carnivores and less in the faeces of herbivores. The species composition in the carnivore baits did not differ from that of the omnivore baits. These data indicate that changes in Scarabaeinae assemblages result from changes in mammal species such as those that have occurred in the Cerrado biome with the conversion to cattle production, which in recent years has caused intense fragmentation of habitats, expansion of agricultural and livestock activities and the introduction of exotic species. The mammal C. brachyurus, vulnerable to extinction in Brazil, should be a focus for future research, since its faeces support a great diversity of dung beetles in the Cerrado.

On the Use of Spores of Coprophilous Fungi Preserved in Sediments to Indicate Past Herbivore Presence

Fungal spores that grew on the faeces of herbivores in the past can be extracted from sediments and used to identify the presence of herbivores in former ecosystems. This review: (i) examines the factors that should be considered when interpreting these fungal spores, (ii) assesses the degree to which they can be used to estimate past herbivore populations and biomass density change, and (iii) identifies gaps in our current understanding that limit, or confound, the information that can be extracted from the fungal spore record. We focus on the life cycles of coprophilous fungi and highlight the importance of understanding spore dispersal mechanisms to ensure robust palaeoecological interpretation. We then discuss how variation in methodological approaches across studies and modifications can influence comparability between studies. The key recommendations that emerge relate to: (i) improving our understanding of the relationship between spores of coprophilous fungi (SCF) and herbivores through the study of the coprophilous fungi succession; (ii) refining our understanding of how climate and environment parameters effect fungal spore abundance, with particular reference to estimating past herbivore biomass density; and (iii) enhancing sedimentary DNA (SedaDNA) analysis to identify SCF that do not allow preservation in a way that allows visual identification. To further this field of study and provide more robust insights into herbivores in the past, we suggest that additional research is required to help to reduce bias during the preparation process, that concertation metrics are used for the quantification of SCF, and that multiple cores should be taken in each site and multiproxy analysis should be utilised.

Extended and cumulative effects of experimentally induced intergroup conflict in a cooperatively breeding mammal

Conflict between rival groups is rife in nature. While recent work has begun exploring the behavioural consequences of this intergroup conflict, studies have primarily considered just the 1–2 h immediately after single interactions with rivals or their cues. Using a habituated population of wild dwarf mongooses (Helogale parvula), we conducted week-long manipulations to investigate longer-term impacts of intergroup conflict. Compared to a single presentation of control herbivore faeces, one rival-group faecal presentation (simulating a territorial intrusion) resulted in more within-group grooming the following day, beyond the likely period of conflict-induced stress. Repeated presentations of outsider cues led to further changes in baseline behaviour by the end of the week: compared to control weeks, mongooses spent less time foraging and foraged closer to their groupmates, even when there had been no recent simulated intrusion. Moreover, there was more baseline territorial scent-marking and a higher likelihood of group fissioning in intrusion weeks. Consequently, individuals gained less body mass at the end of weeks with repeated simulated intrusions. Our experimental findings provide evidence for longer-term, extended and cumulative, effects of an elevated intergroup threat, which may lead to fitness consequences and underpin this powerful selective pressure.

Water sources aggregate parasites with increasing effects in more arid conditions

Shifts in landscape heterogeneity and climate can influence animal movement in ways that profoundly alter disease transmission. Water sources that are foci of animal activity have great potential to promote disease transmission, but it is unknown how this varies across a range of hosts and climatic contexts. For fecal-oral parasites, water resources can aggregate many different hosts in small areas, concentrate infectious material, and function as disease hotspots. This may be exacerbated where water is scarce and for species requiring frequent water access. Working in an East African savanna, we show via experimental and observational methods that water sources increase the density of wild and domestic herbivore feces and thus, the concentration of fecal-oral parasites in the environment, by up to two orders of magnitude. We show that this effect is amplified in drier areas and drier periods, creating dynamic and heterogeneous disease landscapes across space and time. We also show that herbivore grazing behaviors that expose them to fecal-oral parasites often increase at water sources relative to background sites, increasing potential parasite transmission at these hotspots. Critically, this effect varies by herbivore species, with strongest effects for two animals of concern for conservation and development: elephants and cattle.

Antifungal Streptomyces spp., Plausible Partners for Brood-Caring of the Dung Beetle Copris tripartitus.

The dung beetle Copris tripartitus Waterhouse (Coleoptera: Scarabaeidae) is a coprophagous insect that lives in and feeds primarily on the feces of mammalian herbivores and is known to protect their offspring from the pathogen-rich environment by performing parental care for brood balls. Brood balls under continuous management by dung beetle are rarely contaminated by entomopathogenic fungi compared to abandoned brood balls. On the supposition that dung beetles may benefit from mutualistic bacteria that protect their offspring against fungal pathogens, we evaluated the antifungal activities of bacteria isolated from the dung beetle and brood ball. As a result, bacterial isolates, mainly streptomycetes, manifested potent and broad-spectrum antifungal activity against various fungi, including entomopathogens. Of the isolates, Streptomyces sp. AT67 exhibited pronounced antifungal activities. Culture-dependent and independent approaches show that this strain has occurred continuously in dung beetles that were collected over three years. Moreover, metabolic profiling and chemical investigation demonstrated that the strain produced an antifungal polyene macrocyclic lactam, sceliphrolactam, as a major product. Our findings imply that specific symbiotic bacteria of C. tripartitus are likely to contribute brood ball hygiene by inhibiting fungal parasites in the environment.

Complementarity between microhistological analysis and PCR-capillary electrophoresis in diet analysis of goats and cattle using faecal samples

An evaluation is made of the complementarity between two non-invasive techniques, cuticle microhistological analysis (CMA) and PCR-capillary electrophoresis (PCR-CE) DNA-based analysis, for the determination of herbivore diet composition from faecal samples. Cuticle microhistological analysis is based on the different microanatomical characteristics of the epidermal fragments remaining in the faeces. The PCR-CE technique combines PCR amplification of a trnL(UAA) genomic DNA region with amplicon length determination by CE, with this length being characteristic for each species or taxon. A total of 37 fresh stool samples were analyzed, including 16 from feral goats (Capra hircus) from the Tramuntana mountain range (Mallorca, Baleares) and 11 from Bruna dels Pirineus cattle breed (Bos taurus) from the surrounding Montserrat mountain range (Barcelona, Spain). All the animals were in a free grazing Mediterranean pine habitat, dominated by Aleppo pine (Pinus halepensis). The results showed that both techniques detected a similar number of plant components in the faeces of goats and cows. In the case of goats, a positive correlation was obtained between the percentage of samples in which a particular taxon is detected by CMA and the percentage of samples in which that taxon is detected by PCR-CE. This correlation was not observed in the case of cows. It is concluded that PCR-CE is a fast and reliable method to detect the different plant components in the faeces of herbivores. However, it cannot be considered as an alternative to CMA, but as a complementary method, since both techniques can detect some taxa that are not detected by the other technique. In addition, CMA detected the presence of the different taxa in a greater number of samples, and at the same time, it enables quantitative data to be obtained for plant diet composition. The species of herbivore also seems to influence the results obtained by PCR-CE, so more studies are required to address this aspect.

Animal body size distribution influences the ratios of nutrients supplied to plants

Nutrients released through herbivore feces have the potential to influence plant-available nutrients and affect primary productivity. However, herbivore species use nutrients in set stoichiometric ratios that vary with body size. Such differences in the ratios at which nutrients are used leads to differences in the ratios at which nutrients are deposited through feces. Thus, local environmental factors that affect the average body size of an herbivore community (such as predation risk and food availability) influence the ratios at which fecal nutrients are supplied to plants. Here, we assess the relationship between herbivore body size and the nitrogen-to-phosphorus ratios of herbivore feces. We examine how shifts in the average body size of an herbivore community alter the ratios at which nitrogen and phosphorus are supplied to plants and test whether such differences in the stoichiometry of nutrient supply propagate through plants. We show that dung from larger-bodied herbivores contain lower quantities of phosphorus per unit mass and were higher in N:P ratio. We demonstrate that spatial heterogeneity in visibility (a proxy for predation risk and/or food availability) and rainfall (a proxy for food availability), did not affect the overall amount of feces deposited but led to changes in the average body size of the defecating community. Feces deposited in areas of higher rainfall and reduced visibility originated from larger herbivores and were higher in N:P ratios. This indicates that processes that change the size distribution of herbivore communities, such as predation or size-biased extinction, have the potential to alter the nutrient landscape for plants.

Pyrrolic and Dipyrrolic Chlorophyll Degradation Products in Plants and Herbivores.

The degradation of chlorophyll, the omnipresent green pigment, has been investigated intensively over the last 30 years resulting in many elucidated tetrapyrrolic degradation products. With a comparison to the degradation of the structurally similar heme, we hereby propose a novel additional chlorophyll degradation mechanism to mono‐ and dipyrrolic products. This is the first proof of the occurrence of a family of mono‐ and dipyrrols in leaves that are previously only known as heme degradation products. This product family is also found in spit and feces of herbivores with specific metabolomic patterns reflecting the origin of the samples. Based on chromatographic and mass spectrometric evidence as well as on mechanistic considerations we also suggest several tentative new degradation products. One of them, dihydro BOX A, was fully confirmed as a novel natural product by synthesis and comparison of its spectroscopic data.

Apiosordaria nigeriensis (Ascomycota): a new record for the Americas

Abstract Apiosordaria is a genus of fungus with species commonly reported inhabiting soil or herbivore feces. However, studies related to the association of representatives of this genus to plants, especially in semi-arid ecosystems, are still non-existent. In this work we documented a new occurrence for Brazil of a species of Apiosordaria, associated with the palm Syagrus coronata. The collections were carried out at the Raso da Catarina Ecological Station and the analyzes were carried out at the Laboratory of Sciences of the Bahia State University, Campus VIII, Paulo Afonso. From the topographic analysis of the plant substrate in stereomicroscope and the evaluation of fungal structures under optical light microscope, the species was identified as Apiosordaria nigeriensis. This fungus was reported for the first time in Enugu, Nigeria, after being isolated from soil samples. In this work, we report the second occurrence of A. nigeriensis to the world, being the first to Brazil, representing the first record for the Americas, and highlighting the palm S. coronata as the first botanical host colonized by the species. These data broaden the knowledge about the geographic distribution of the genus, especially on the microdiversity for the caatinga biome.

Assessment of three indigenous South African herbivores as potential reservoirs and vectors of antibiotic-resistant Escherichia coli

Due to limited data available on the presence of antibiotic-resistant (ABR) bacteria in faeces of wild herbivores in South Africa, this study analysed resistance patterns for Escherichia coli isolates from wildebeest, zebra and giraffe in addition to pet and farm pig faeces. Total and faecal coliforms and E. coli were quantified in faecal matter using a most probable number (MPN) guideline procedure. Antibiotic resistance profiles against 12 selected antibiotics representing seven classes were determined for 30 randomly selected E. coli isolates from each animal using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) disk diffusion procedure. While log10 MPN values per gram of animal faeces for total/faecal coliforms ranged from 4.51/4.11 to 5.70/5.50, the E. coli MPN values were in a range of 3.43–5.14. The proportion of ABR E. coli isolates ranged from 43% (giraffe) to 93% (zebra). About 47% of E. coli isolates from zebra faeces were categorized as multidrug-resistant (MDR), while for wildebeest and giraffe, no MDR isolates were detected. In comparison, 10% of E. coli isolates from pet pig and about 7% from farm pig faeces were categorized as MDR. Although most MDR isolates were resistant to at least one β-lactam antibiotic, only one MDR isolate from farm pig faeces was resistant to both norfloxacin and ciprofloxacin, the two fluoroquinolones tested. However, no resistance was detected to the tested carbapenems and tigecycline. The results of this study indicate that indigenous South African herbivores may serve as potential reservoirs and vectors for the dissemination of ABR E. coli strains.

Fecal-Derived Phenol Induces Egg-Laying Aversion in Drosophila

Feces is an abundant, rich source of energy, utilized by a myriad of organisms, not least by members of the order Diptera, i.e., flies. How Drosophila melanogaster reacts to fecal matter remains unclear. Here, we examined oviposition behavior toward a range of fecal samples from mammals native to the putative Southeast African homeland of the fly. We show that D.melanogaster display a strong oviposition aversion toward feces from carnivorous mammals but indifference or even attraction toward herbivore dung. We identify a set of four predictor volatiles, which can be used to differentiate fecal from non-fecal matter, as well as separate carnivore from herbivore feces. Of these volatiles, phenol-indicative of carnivore feces-confers egg-laying aversion and is detected by a single class of sensory neurons expressing Or46a. The Or46a-expressing neurons are necessary and sufficient for oviposition site aversion. We further demonstrate that carnivore feces-unlike herbivore dung-contain a high rate of pathogenic bacteria taxa. These harmful bacteria produce phenol from L-tyrosine, an amino acid specifically enriched in high protein diets, such as consumed by carnivores. Finally, we demonstrate that carnivore feces, as well as phenol, is also avoided by a ball-rolling species of dung beetle, suggesting that phenol is a widespread avoidance signal because of its association with pathogenic bacteria.

An integrative taxonomy on the locally endangered species of the Korean Scarabaeus (Coleoptera, Scarabaeidae).

The ball-rolling dung beetles of the genus Scarabaeus are very ecologically important for the recycling of feces of large herbivores and the related nature management. There has been a significant decline, however, in the numbers of many species at the population and individual levels. S. typhon is currently thought to be the sole member of Scarabaeus distributed in Korea; however, that species underwent serious local extinctions in the 1970s. Before planning a full-scale species recovery, it is important to have an understanding of the exact species diversity and genetic structures of the focal species. We therefore attempted an integrative taxonomy focused on the Korean population of S. typhon and also on S. pius and S. sacer, which were once thought to be distributed in Korea, using both morphological and molecular approaches. The results of both approaches reveal the Korean species of Scarabaeus to be S. typhon and S. pius. In particular, our molecular results inferred from cytochrome c oxidase subunit I genetic analysis show that S. typhon should be considered a single species despite having various haplotypes throughout its wide geographical range from Europe to Korea. We identified two distinct lineages of S. pius (groups A and B) across a wide distributional range. We conclude that the Korean specimens of S. pius belong to group A and that S. pius is new to Korea under the current taxonomic treatment.

Nitrogen cycling in an extreme hyperarid environment inferred from δ(15)N analyses of plants, soils and herbivore diet.

Climate controls on the nitrogen cycle are suggested by the negative correlation between precipitation and δ15N values across different ecosystems. For arid ecosystems this is unclear, as water limitation among other factors can confound this relationship. We measured herbivore feces, foliar and soil δ15N and δ13C values and chemically characterized soils (pH and elemental composition) along an elevational/climatic gradient in the Atacama Desert, northern Chile. Although very positive δ15N values span the entire gradient, soil δ15N values show a positive correlation with aridity as expected. In contrast, foliar δ15N values and herbivore feces show a hump-shaped relationship with elevation, suggesting that plants are using a different N source, possibly of biotic origin. Thus at the extreme limits of plant life, biotic interactions may be just as important as abiotic processes, such as climate in explaining ecosystem δ15N values.