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Invasive species can have complex direct and indirect impacts on ecosystems. The impacts of invasive prey species on native prey can be difficult to observe if the latter migrate seasonally, and when the interaction is indirect. We hypothesize that invasive lagomorphs and snow dynamics indirectly drive predation risk for guanaco by puma. We employed camera-trapping data collected over multiple years and seasons in an altitudinal gradient in the Andes of Central Chile. We predicted a high spatial and temporal association between puma and lagomorph detections, given these prey species comprise most of puma diet in the area. We also expected a higher spatiotemporal association between guanaco and puma detections towards higher snow cover in the study area, because of downward altitudinal migration of the ungulate. We obtained 4863 mammalian detections. Our data shows that the detection of puma was positively associated with hare capture rate year-round. In addition, puma detection was positively associated with the interaction of snow cover and guanaco capture rate. Puma temporal activity strongly overlapped with hare, whereas puma apparently increased diurnal activity with an increase in guanaco capture rate. Predation risk for guanaco increased when snow cover was higher and decreased when guanaco migrated to higher altitudes during dryer months. We conclude it is of conservation concern that lagomorphs may be subsidizing pumas and modifying patterns of consumptive and non-consumptive effects of the predator on native prey populations. [ABSTRACT FROM AUTHOR]

Semiarid Patagonia represents 25% of the rangeland area in Argentina, and sheep overgrazing has degraded about a third of it in the past. In this century, depleted domestic stocks have mostly stabilized, but Guanaco populations have grown. These native camelids share habitat and diets with sheep, but their effect on vegetation is poorly understood and has long been debated. We set up an exclusion experiment in Monte León and Cañadón Vaca, a semiarid shrubland grassland in southern Patagonia, currently grazed only by guanacos. Vegetation baselines were studied in 2016 in twelve plots, and half of them were protected from guanaco grazing. Thirty-six plots were cleared to study revegetation. Vegetation was reassessed in 2021, and changes were evaluated using a paired t -test. Within protected plots, vegetation cover increased, bare soil diminished, and vegetated patches grew in size, but the density of the patch-interpatch arrangement did not change. Biodiversity, measured by richness and the Shannon-Wiener (SW) index, grew significantly. Nutrient recycling increased, as did the Stability and Infiltration Land Function indexes, although these last differences were not significant. Vegetation cover under guanaco grazing also increased, mainly due to the growth of dwarf shrubs, a typical tendency in sheep grazing-induced transitions in the region. Vegetated patches under grazing fragmented, resulting in smaller patches and denser patch structures, while diversity and land function indexes remained unchanged. Young plants established in cleared plots without guanacos showed higher cover density and individual size. These effects are similar to those observed in numerous experimental sheep exclosures. Guanaco grazing may thus prevent restoration and contribute to the generalized land degradation processes that overgrazing has been causing in Patagonia for over a century. [ABSTRACT FROM AUTHOR]

Abstract Background Alpaca is a domestic South American camelid probably arising from the domestication of two wild camelids, the vicugna and the guanaco. Two phenotypes are described for alpaca, known as huacaya and suri. Huacaya fleece is characterized by compact, soft, and highly crimped fibers, while suri fleece is longer, straight, less crimped, and lustrous. The gene variants determining these phenotypes are still unknown, although previous studies suggested a dominant inheritance of the suri. Based on that, the aim of this study was the identification of the gene variants determining alpaca coat phenotypes through whole genome sequencing (WGS) analysis. Results The sample used includes two test-cross alpaca families, suri × huacaya, which produced two offspring, one with the suri phenotype and one with the huacaya phenotype. The analyzed sample was expanded through the addition of WGS data from six vicugnas and six guanacos; this because we assumed the absence of the gene variants linked to the suri phenotype in these wild species. The analysis of gene variant segregation with the suri phenotype, coupled with the filtering of gene variants present in the wild species, disclosed the presence in all the suri samples of a premature termination codon (PTC) in TRPV3 (transient receptor potential cation channel subfamily V member 3), a gene known to be involved in hair growth and cycling, thermal sensation, cold tolerance and adaptation in several species. Mutations in TRPV3 were previously associated with the alteration of hair structure leading to an impaired formation of the hair canal and the hair shaft in mouse. This PTC in TRPV3, due to a G > T substitution (p.Glu475*), results in a loss of 290 amino acids from the canonical translated protein, plausibly leading to a physiological dysfunction. Conclusion The present results suggest that the suri phenotype may arise from a TRPV3 gene variant which may explain some of the suri features such as its longer hair fibre with lower number of cuticular scales compared to huacaya.

Simple Summary: The South American landscape has changed since the Spanish conquest, largely due to the introduction of foreign plants and animals, often at the expense of native species. In the south, Patagonia became a world-class sheep production center, and the native guanaco has almost disappeared. In Peru, guanacos are critically endangered, and an important local increase in their numbers is presently causing a conflict with local farmers in two southern communities. We studied guanaco movements in the area over a year using information from field surveys and remote sensing data from GPS-collared animals. We found that guanaco family groups did not invade agricultural fields, but free-ranging bands of young males and single adults did, perhaps pushed by the greater number of animals and decreased food resources. Information about the losses suffered by the farmers was obtained through interviews. The vast majority felt that guanacos are a problem to be resolved by building better fences, increasing security, or even illegal hunting. Although they are aware that guanacos are protected by law, 92% saw no present or future value in protecting the guanaco. These results show how much research and public education remain to be done to protect the Peruvian guanaco. The Peruvian guanaco (Lama guanicoe cacsilensis) is classified as being "in critical danger of extinction" by the government. In this study, we evaluate how the conflict between farmers and guanacos in the Susapaya and Estique Districts, Tacna Department (Southern Peru) may represent a threat to their survival. To evaluate the situation, we 1. Conducted field surveys to monitor guanaco presence, 2. Used available remote sensing data to map guanaco movement, and 3. interviewed the impacted farmers concerning their losses. Remote sensing data showed that sedentary guanaco family groups located in prime steppe vegetation habitats never entered agricultural areas, while field surveys showed that bachelor bands and solitary individuals did, perhaps seeking forage due to growing population pressure. Interview data found that 90% of community farmers felt that guanacos were a problem best resolved by better fencing (45%), hunting (19%), or increased security (16%), and 92% saw no value in the conservation of the species. Hunting is illegal, given the critically endangered status of guanacos in Peru, so additional efforts are needed to both educate those who feel guanacos are a menace and involve them in efforts to preserve the species. [ABSTRACT FROM AUTHOR]

Background: Alpaca is a domestic South American camelid probably arising from the domestication of two wild camelids, the vicugna and the guanaco. Two phenotypes are described for alpaca, known as huacaya and suri. Huacaya fleece is characterized by compact, soft, and highly crimped fibers, while suri fleece is longer, straight, less crimped, and lustrous. The gene variants determining these phenotypes are still unknown, although previous studies suggested a dominant inheritance of the suri. Based on that, the aim of this study was the identification of the gene variants determining alpaca coat phenotypes through whole genome sequencing (WGS) analysis. Results: The sample used includes two test-cross alpaca families, suri × huacaya, which produced two offspring, one with the suri phenotype and one with the huacaya phenotype. The analyzed sample was expanded through the addition of WGS data from six vicugnas and six guanacos; this because we assumed the absence of the gene variants linked to the suri phenotype in these wild species. The analysis of gene variant segregation with the suri phenotype, coupled with the filtering of gene variants present in the wild species, disclosed the presence in all the suri samples of a premature termination codon (PTC) in TRPV3 (transient receptor potential cation channel subfamily V member 3), a gene known to be involved in hair growth and cycling, thermal sensation, cold tolerance and adaptation in several species. Mutations in TRPV3 were previously associated with the alteration of hair structure leading to an impaired formation of the hair canal and the hair shaft in mouse. This PTC in TRPV3, due to a G > T substitution (p.Glu475*), results in a loss of 290 amino acids from the canonical translated protein, plausibly leading to a physiological dysfunction. Conclusion: The present results suggest that the suri phenotype may arise from a TRPV3 gene variant which may explain some of the suri features such as its longer hair fibre with lower number of cuticular scales compared to huacaya. [ABSTRACT FROM AUTHOR]

National parks (NP) are the last refugia of forests dominated by the Nothofagus species in Chile. However, frequent, careless human-caused fires are destroying these forests even within the national parks. After large-scale fires, N. pumilio stands are unable to recover naturally neither in generative nor in vegetative ways and artificial regeneration must be resorted to in order to maintain their extent. However, even artificial regeneration is not successful without protection against browsing. Therefore, the aim of this study was to experimentally test a range of repellents and other methods of mechanical protection of seedlings against browsing. Five replicates of plots were placed in Torres del Paine NP, in different habitat conditions and with different methods of protection against browsing (11 repellents, wire mesh, plastic tube and control). In each plot, 12 seedlings were treated with each type of protection. In our experiment, only 8% of the seedlings were damaged by browsing, while the mortality rate was 38%. The results indicate a more significant effect of abiotic factors (mainly frost, drought or wind) on seedling mortality than browsing. In parallel, however, it is clear that, compared with the control, six of the eleven repellents used in the experiment showed a significantly positive effect. We suggest the use of plastic tubes as the best option to protect seedlings, which, in addition to providing 100% protection against browsing, are likely to provide more favourable microclimatic conditions for seedlings, similar to leaving the burned snags.

Abstract Background Alpaca (Vicugna pacos), llama (Lama glama), vicugna (Vicugna vicugna) and guanaco (Lama guanicoe), are the camelid species distributed over the Andean high-altitude grasslands, the Altiplano, and the Patagonian arid steppes. Despite the wide interest on these animals, most of the loci under selection are still unknown. Using whole-genome sequencing (WGS) data we investigated the occurrence and the distribution of Runs Of Homozygosity (ROHs) across the South American Camelids (SACs) genome to identify the genetic relationship between the four species and the potential signatures of selection. Results A total of 37 WGS samples covering the four species was included in the final analysis. The multi-dimensional scaling approach showed a clear separation between the four species; however, admixture analysis suggested a strong genetic introgression from vicugna and llama to alpaca. Conversely, very low genetic admixture of the guanaco with the other SACs was found. The four species did not show significant differences in the number, length of ROHs (100-500 kb) and genomic inbreeding values. Longer ROHs (> 500 kb) were found almost exclusively in alpaca. Seven overlapping ROHs were shared by alpacas, encompassing nine loci (FGF5, LOC107034918, PRDM8, ANTXR2, LOC102534792, BSN, LOC116284892, DAG1 and RIC8B) while nine overlapping ROHs were found in llama with twenty-five loci annotated (ERC2, FZD9, BAZ1B, BCL7B, LOC116284208, TBL2, MLXIPL, PHF20, TRNAD-AUC, LOC116284365, RBM39, ARFGEF2, DCAF5, EXD2, HSPB11, LRRC42, LDLRAD1, TMEM59, LOC107033213, TCEANC2, LOC102545169, LOC116278408, SMIM15, NDUFAF2 and RCOR1). Four overlapping ROHs, with three annotated loci (DLG1, KAT6B and PDE4D) and three overlapping ROHs, with seven annotated genes (ATP6V1E1, BCL2L13, LOC116276952, BID, KAT6B, LOC116282667 and LOC107034552), were detected for vicugna and guanaco, respectively. Conclusions The signatures of selection revealed genomic areas potentially selected for production traits as well as for natural adaptation to harsh environment. Alpaca and llama hint a selection driven by environment as well as by farming purpose while vicugna and guanaco showed selection signals for adaptation to harsh environment. Interesting, signatures of selection on KAT6B gene were identified for both vicugna and guanaco, suggesting a positive effect on wild populations fitness. Such information may be of interest to further ecological and animal production studies.

National parks (NP) are the last refugia of forests dominated by the Nothofagus species in Chile. However, frequent, careless human-caused fires are destroying these forests even within the national parks. After large-scale fires, N. pumilio stands are unable to recover naturally neither in generative nor in vegetative ways and artificial regeneration must be resorted to in order to maintain their extent. However, even artificial regeneration is not successful without protection against browsing. Therefore, the aim of this study was to experimentally test a range of repellents and other methods of mechanical protection of seedlings against browsing. Five replicates of plots were placed in Torres del Paine NP, in different habitat conditions and with different methods of protection against browsing (11 repellents, wire mesh, plastic tube and control). In each plot, 12 seedlings were treated with each type of protection. In our experiment, only 8% of the seedlings were damaged by browsing, while the mortality rate was 38%. The results indicate a more significant effect of abiotic factors (mainly frost, drought or wind) on seedling mortality than browsing. In parallel, however, it is clear that, compared with the control, six of the eleven repellents used in the experiment showed a significantly positive effect. We suggest the use of plastic tubes as the best option to protect seedlings, which, in addition to providing 100% protection against browsing, are likely to provide more favourable microclimatic conditions for seedlings, similar to leaving the burned snags. [ABSTRACT FROM AUTHOR]

Background: Alpaca (Vicugna pacos), llama (Lama glama), vicugna (Vicugna vicugna) and guanaco (Lama guanicoe), are the camelid species distributed over the Andean high-altitude grasslands, the Altiplano, and the Patagonian arid steppes. Despite the wide interest on these animals, most of the loci under selection are still unknown. Using whole-genome sequencing (WGS) data we investigated the occurrence and the distribution of Runs Of Homozygosity (ROHs) across the South American Camelids (SACs) genome to identify the genetic relationship between the four species and the potential signatures of selection. Results: A total of 37 WGS samples covering the four species was included in the final analysis. The multi-dimensional scaling approach showed a clear separation between the four species; however, admixture analysis suggested a strong genetic introgression from vicugna and llama to alpaca. Conversely, very low genetic admixture of the guanaco with the other SACs was found. The four species did not show significant differences in the number, length of ROHs (100-500 kb) and genomic inbreeding values. Longer ROHs (> 500 kb) were found almost exclusively in alpaca. Seven overlapping ROHs were shared by alpacas, encompassing nine loci (FGF5, LOC107034918, PRDM8, ANTXR2, LOC102534792, BSN, LOC116284892, DAG1 and RIC8B) while nine overlapping ROHs were found in llama with twenty-five loci annotated (ERC2, FZD9, BAZ1B, BCL7B, LOC116284208, TBL2, MLXIPL, PHF20, TRNAD-AUC, LOC116284365, RBM39, ARFGEF2, DCAF5, EXD2, HSPB11, LRRC42, LDLRAD1, TMEM59, LOC107033213, TCEANC2, LOC102545169, LOC116278408, SMIM15, NDUFAF2 and RCOR1). Four overlapping ROHs, with three annotated loci (DLG1, KAT6B and PDE4D) and three overlapping ROHs, with seven annotated genes (ATP6V1E1, BCL2L13, LOC116276952, BID, KAT6B, LOC116282667 and LOC107034552), were detected for vicugna and guanaco, respectively. Conclusions: The signatures of selection revealed genomic areas potentially selected for production traits as well as for natural adaptation to harsh environment. Alpaca and llama hint a selection driven by environment as well as by farming purpose while vicugna and guanaco showed selection signals for adaptation to harsh environment. Interesting, signatures of selection on KAT6B gene were identified for both vicugna and guanaco, suggesting a positive effect on wild populations fitness. Such information may be of interest to further ecological and animal production studies. [ABSTRACT FROM AUTHOR]

The Peruvian guanaco (Lama guanicoe cacsilensis) is classified as being “in critical danger of extinction” by the government. In this study, we evaluate how the conflict between farmers and guanacos in the Susapaya and Estique Districts, Tacna Department (Southern Peru) may represent a threat to their survival. To evaluate the situation, we 1. Conducted field surveys to monitor guanaco presence, 2. Used available remote sensing data to map guanaco movement, and 3. interviewed the impacted farmers concerning their losses. Remote sensing data showed that sedentary guanaco family groups located in prime steppe vegetation habitats never entered agricultural areas, while field surveys showed that bachelor bands and solitary individuals did, perhaps seeking forage due to growing population pressure. Interview data found that 90% of community farmers felt that guanacos were a problem best resolved by better fencing (45%), hunting (19%), or increased security (16%), and 92% saw no value in the conservation of the species. Hunting is illegal, given the critically endangered status of guanacos in Peru, so additional efforts are needed to both educate those who feel guanacos are a menace and involve them in efforts to preserve the species.

This is the first morpho‐histological comparison of guanaco ovaries between reproductive (long‐days) and non‐reproductive (short‐days) seasons, and oestrogen receptor‐alpha (ERα) and beta (ERβ) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long‐day ovaries than short‐days, consistent with ovarian activity in this season. Differential expression of ERα and ERβ was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non‐reproductive seasons of guanaco ovaries. [ABSTRACT FROM AUTHOR]

Se estudiaron los restos faunísticos no ingeridos recuperados en el interior y bajo un nido de carancho (Caracara plancus) localizado en los niveles aterrazados del interfluvio Coyle-Gallegos con el objetivo general de evaluar su papel como agente tafonómico. El nido fue construido sobre una mata de calafate (Berberis sp.), ubicada en el centro de una concentración de carcasas de guanacos (Lama guanicoe) muertos por estrés invernal en el año 2020. Durante las tareas de campo se describieron y tomaron medidas del nido y se colectó su contenido. En el laboratorio realizamos identificaciones anatómicas y taxonómicas, además de relevar distintas variables tafonómicas. Los resultados indican el predominio de restos de guanaco, seguido por zorrino (Conepatus chinga), liebre (Lepus europaeus) y choique (Rhea pennata). Gran parte de los restos están desarticulados, fracturados y presentan marcas de mamíferos carnívoros. Al considerar los nidos de carancho en el marco de la arqueología regional, se destaca que el mayor potencial de contaminación del registro con los huesos acumulados por caranchos se daría en cañadones y roqueríos. Las observaciones y los resultados de los análisis permiten reconocer la incidencia del carancho como agente formador del registro, lo cual es relevante dado que por la escasa evidencia de su accionar, no suele ser considerado al momento de evaluar las historias tafonómicas de los conjuntos arqueológicos.

El sitio Zoko Andi 1 (curso inferior del río Colorado, provincia de Buenos Aires) es una base residencial reocupada por cazadores-recolectores durante dos momentos del Holoceno tardío, el inicial (ca. 1500-1300 años AP) y el final (ca. 800-400 años AP). Entre las numerosas evidencias recuperadas se destacan los conjuntos zooarqueológicos compuestos por especies de tamaño mayor y menor. Un rasgo sobresaliente es la elevada cantidad de fragmentos óseos de guanaco. En este trabajo se analizan los restos correspondientes a esta especie (N= 73143) con el fin de evaluar la intensidad en su aprovechamiento. Los resultados obtenidos indicaron que esta presa fue explotada intensamente para el consumo sistemático de carne, médula y grasa ósea durante el Holoceno tardío inicial y final. El modelo de subsistencia elaborado para el área de estudio proponía que la intensidad en la explotación de presas fue propia del Holoceno tardío final (ca. 1000-250 años AP). Sin embargo, el sitio Zoko Andi 1 evidencia que estas estrategias económicas habrían sido puestas en práctica con anterioridad, durante el Holoceno tardío inicial (ca. 1500-1300 años AP). La intensidad en el tratamiento de las carcasas se habría producido debido a una ocupación humana intensa y prolongada en sectores ribereños altamente productivos.

Understanding competitive interactions is essential to properly inform management strategies, in particular in the context of livestock‐wildlife conflict across a degraded land, such as the case of wild guanacos in Patagonia. Guanacos are historically perceived by ranchers as livestock's main competitors, and there is a growing demand for reducing their numbers. However, both competition theory and available evidence suggest a more complex interaction than the one assumed by the current management approach. This study aimed to test the occurrence of competitive exclusion of guanacos by domestic sheep at intra‐ranch scale. We assessed the spatial segregation of guanacos and sheep and compared guanaco occupancy patterns within a sheep ranch with those recorded within an adjacent protected area free from livestock. The probability of a group of herbivores being sheep instead of guanacos increased in bottom valleys and smaller paddocks and decreased as the distance to water increased. These results agree with the expected patterns of sheep habitat use resulting from physiological restrictions and grazing behaviour. Occupancy patterns within the ranch showed a higher proportion of guanacos in ridges, away from water sources and in larger paddocks, opposing those observed in the sheep‐free area where guanacos occupied mostly bottom valleys, irrespective of the distance to water. Areas used consistently by guanacos showed a higher per cent cover of preferred forage and basal‐plant cover, indicating a better range condition than those used predominately by sheep. Our results add to the solid body of evidence on spatial segregation of these species at coarser spatial scales, support the competitive exclusion of guanacos by sheep and suggest that intra‐ranch coexistence is possible because guanacos occupy areas underused or inaccessible to sheep. Under these conditions, it is unlikely that guanaco culling will improve sheep production and the empirical verification of the assumptions underlying current management initiatives becomes crucial. [ABSTRACT FROM AUTHOR]

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Previous attempts to address the presence of interspecific competition between domestic livestock and wild ungulates have focused largely on habitat or dietary overlaps. Although overlaps in habitat or diet create opportunities for competition to occur between species, competition only results from such overlap if it affects one or both species negatively. Less attention has been afforded to possible behavioural modifications induced in wildlife by competition with domestic livestock. Here, we investigated the effects of the presence of livestock on feeding behaviour of guanaco (Lama guanicoe) in southern Patagonia, using focal sampling of individuals during foraging bouts, with instantaneous scan samples to estimate group behavioural budgets. We recorded guanaco bite and step rates, used as proxies of foraging intake and selectivity, from four different study sites over eight consecutive seasons. We also estimated sheep and guanaco densities per site, along with vegetation biomass availability. As in other ungulates, bite rates of guanaco appear to be highly flexible and generally increased with vegetation biomass availability. However, as sheep densities and thus additional grazing pressure increased, guanaco foraging strategy compensated by increasing bite rates when foraging vegetation was scarce, indicating further likelihood of competition. Additionally, scan samples indicated that the probability of guanaco feeding occurring at any one time was higher in areas shared with domestic sheep compared to national parks, suggesting guanaco have to focus more on feeding than other behaviours when sheep are present. [ABSTRACT FROM AUTHOR]

Los estudios relacionados con el arte rupestre de la región de Aysén, Patagonia Central, Chile, se han enfocado en los valles de los ríos Ibáñez y Jeinimeni. Actualmente sólo se cuenta con dataciones absolutas en algunos sitios del río Ibáñez, las cuales en asociación con los tipos de motivos presentes en el arte rupestre de ambas áreas y la secuencia estilística planteada en Patagonia Centro-Meridional, han permitido una cronología que va desde 6.000 años AP, hasta la llegada de los colonos. Dentro de los diseños reconocidos destacan las representaciones de guanacos (Lama guanicoe), en diversas formas y tamaños. A partir de este tipo de motivo identificado en cuatro sitios del valle del río Ibáñez y tres en Jeinimeni, este trabajo intenta abordar la posible diferenciación en cuanto a la forma de ocupar el espacio geográfico por parte de los grupos cazadores recolectores que habitaron ambas áreas, basándose en la morfología, disposición y emplazamiento de estas representaciones.

Most food web models fail to account for the full complexity of interactions within a community, particularly where microbes are involved. Carcasses are microbe‐rich resources and may represent a common nexus for the macrobiome and microbiome, effectively uniting autotrophs, consumers, predators and microbiota.We evaluated the role of carcasses as multitrophic resources and explored dietary partitioning for a sexually dimorphic obligate scavenger known for its hierarchical social system. This study was set in a well‐studied community of camelids Vicugna, Lama guanicoe, pumas Puma concolor and Andean condors Vultur gryphus in the Andes. We hypothesized that condors, by feeding on trophically distinct dietary substrates within any given carcass, would have highly variable trophic position (TP) values. Furthermore, we expected that the microbial consumers within the carcass would inflate TP values in both, the carrion and the condors. Thus, we expected that the trophic heterogeneity within a carcass could facilitate sex‐based dietary partitioning in condors.We used a multifaceted approach to assess the foraging of Andean condors, using regurgitated pellet and bulk isotopic analyses, and also quantified the TP of the entire community of graminoids, camelids, camelid carrion, pumas, and female and male condors employing compound‐specific stable isotopes analysis of amino acids.Our analysis of condor pellets and bulk isotopes revealed non‐trivial plant consumption, close to 10% of condor diet. Isotope analysis of amino acids revealed that condors had highly variable TPs (2.9 ± 0.3) compared to pumas (3.0 ± 0.0) and camelids (2.0 ± 0.1), likely representing 'trophic omnivory', wherein the condors consume plants (TP = 1.0 ± 0.1) and microbe‐colonized carrion (2.3 ± 0.1). Female condors exhibited a TP (2.8 ± 0.2) lower than strict carnivory, suggesting that they consume more plant biomass in a carcass, while males (TP = 3.1 ± 0.3) are likely consuming more of the microbe‐rich animal tissue.Our study highlights that carcasses represent a trophically heterogeneous resource and that vertebrate scavengers can feed across trophic groups within the carcass, from autotrophs to secondary consumers, and from both the macrobiome and microbiome. Thus, integration of microbes in macroecological contexts can help to resolve trophic identity, and better characterize the importance of microbes in detritivorous and omnivorous species. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Many South American dry woodlands lack good historical or paleoecological baseline data to inform restoration and conservation. However, functionalist approaches such as those popularized by rewilding suggest that functional interactions producing target ecosystem processes are valid even without data confirming compositionalist values such as a long coevolutionary histories or known historical range overlaps of target species. In central Chile, the guanaco (Lama guanicoe) has been extirpated but is known to browse trees in other regions of South America, and the tree Vachellia [Acacia] caven shows adaptations to browsing but has no extant browsers within its Chilean range. Both species are native to Chile but there are no data to assess their historical levels of interaction. Here we test the hypothesis that they can act as mutual "Eltonian proxy" species: interacting species for which we lack sufficient data (the Eltonian shortfall) to prove they are not proxies. Specifically we predict that they have complementary adaptations such that guanacos will browse Vachellia [Acacia] caven and the latter will show adaptive responses to their browsing. We introduced five guanacos into an enclosure of Vachellia [Acacia] caven "espinal" woodland, and over two years measured the growth responses of individual branches, compared to branches of trees in an area without browsing. We predicted that Vachellia [Acacia] caven would show compensatory growth in response to guanaco browsing resulting in an increase in branching. Guanacos browsed throughout the two years. In the presence of guanaco browsing, Vachellia [Acacia] caven branches grew longer, grew more sub-branches, and showed more densely streamlined branch architectures. These results indicate that guanacos could be used to substitute anthropogenic pruning as a restoration and management technique in Vachellia [Acacia] caven "espinal" woodlands. However, other extinct megaherbivores or extirpated deer may also be key components of a past herbivore community to which Vachellia [Acacia] caven was adapted. Further attention to a network of multiple interacting browsers, and their indirect and nontrophic effects, is an area for further research. • Native trees (Vachellia (Acacia) caven) in open woodlands show compensatory growth, a potential adaptation to browsing. • We tested whether V. caven and regionally extirpated guanacos Lama guanicoe show reciprocal browsing adaptations. • Naïve guanacos spontaneously browsed Acacia caven branches and leaves. • Browsed Acacia caven grew longer branches, with more sub-branches and in a more tightly bunched shape compared to controls. • Guanacos could be used as a natural restoration method to mimic known positive impacts of pollarding on open woodlands. [ABSTRACT FROM AUTHOR]

The factors that regulate the abundance and distribution of wild herbivores are key components of a species' ecology and include bottom-up and top-down mechanisms, as well as aspects related to social organization. In territorial ungulates, males distribute themselves to enhance access to females by anticipating how resources will influence female distribution. Although the variables that influence the distribution of territorial males have implications for mating opportunities and reproductive success, these relationships remain largely unknown. We assessed how bottom-up, top-down and social factors influence the spatial distribution of territorial male guanacos (Lama guanicoe) in a semiarid ecosystem during three periods of the reproductive season, in a population with two alternative mating tactics: a resource-defence tactic adopted by family group males and a clustered territorial tactic adopted by solitary males. We conducted ground surveys of males from both social units and used density surface models to assess the influence of primary productivity, predation risk and female grouping on their spatial distribution. Our results showed that territorial males were more abundant in areas of increased primary productivity during the group formation period in years of good plant growth and higher number of females/female groups throughout the reproductive season, suggesting that both bottom-up and social traits regulate their spatial distribution. Predation risk did not significantly influence the abundance of territorial males. Overall, our research contributes to the understanding of territorial systems in ungulates and reinforces the current theory that bottom-up processes are relatively more important than top-down processes in regulating populations of large herbivores. Significance statement: Many factors operate together to regulate the abundance and spatial distribution of territorial ungulates. Understanding these relationships has implications for mating opportunities and reproductive success. In this study, we combined field data with density surface models to assess the influence of bottom-up, top-down and social factors on the spatial distribution of a territorial ungulate during the reproductive season. We used the guanaco (Lama guanicoe), the main wild ungulate of the southern region of South America, as a study model. Our results suggest that in low-productivity environments, bottom-up (primary productivity) and social traits (female grouping) predominate in regulating the spatial distribution of territorial male guanacos, rather than top-down factors (predation risk). We highlight the possibility that different populations of herbivores respond differently depending on environmental conditions that shape both the quality and quantity of forage and predation. [ABSTRACT FROM AUTHOR]

This research work allowed the development of a scientific approach to a remedy widely used until today in ranches or rural posts as an alternative medicine: the “guanaco stone” or bezoar. Bezoars are compactions of various chemical substances, hairs, vegetable fibers and foreign bodies, which are formed mainly between the divisions of the stomach of guanacos (Lama guanicoe). The ethnomedicine of this Patagonian region uses powdered bezoars ingested with water or in infusions, as a medicine that improves digestive and renal functions, and especially alexipharmaceuticals. The objective of this trial was to find “in vitro” the pharmacological foundations of bezoars. Samples of bezoars, obtained from the local refrigerator, were used in the test. For this, their density, colors, and hardness were determined. One of the bezoars was totally pulverized, the powder obtained was observed under an optical microscope with a magnification of 1000×. Subsequently, the chemical composition was sought by examining the presence of P, K, and N, as well as the pH. The results made it possible to determine the pH was neutral and the presence of P, N, and K was medium. It is concluded in this first approach to the subject that according to these determinations, bezoars can act via two mechanisms: the presence of phosphates acts as chelators of ingested toxins, facilitating their elimination from the body, but also the minerals that together stimulate the secretion of acid gastric and digestive enzymes.

The present study examined the effects of different photoperiods and melatonin treatment on plasma prolactin concentrations in guanacos, a South American camelid, in captivity. Fourteen adult female guanacos, not gestating or lactating and isolated from males, were studied. The control group was exposed to natural daylight, during short days (N = 7, 10L:14D) and long days (N = 7, 16L:8D). The treatment group (N = 7, 10L:14D) received melatonin implants every 23 days for 6 weeks during long days. Blood samples were taken at intervals of 1 week for 3 weeks, starting the third week of treatment. Prolactin concentrations were measured using competitive ELISA. Plasma concentrations of prolactin in non‐lactating female guanacos have seasonal changes, with a higher concentration (p <.001) in short days (3.50 ± 2.24 ng/ml) than long days (1.10 ± 0.91 ng/ml). Melatonin treatment significantly decreases (p <.05) plasma concentrations of prolactin on the 21st day after the treatment. These findings are the first report of an endogenous circannual rhythm of plasma prolactin concentration and the action of melatonin treatment on prolactin secretion in this wild camelid. [ABSTRACT FROM AUTHOR]

• The pineal gland of adult guanacos is sensitive to seasonal changes in day length. • E2, FSH and LH concentrations are higher during long days than short days. • Melatonin receptor 1A (Mel1A) and kisspeptin (KISS1) were detected in guanacos. The guanaco, a wild South American camelid, is renowned for its remarkable resilience to extreme conditions. Despite this, little is known about how reproductive hormones in female camelids are influenced during their seasonal breeding period, which occurs during long photoperiod. To explore this, the study investigated the response of the hypothalamic-pituitary–gonadal axis in female guanacos during short days (10L:14D; July) and long days (16L:8D; December) in the Mediterranean ecosystem (33°38′28″S, 70°34′27″W). Blood samples from 14 adult animals were collected, and measurements of melatonin, 17β-estradiol, FSH, and LH concentrations were taken. The results showed that melatonin concentration was lower (P < 0.05) during long days than short days, whereas 17β-estradiol, FSH, and LH concentrations were higher (P < 0.05) during long days compared to short days. Furthermore, the study detected the expression of the melatonin receptor 1A and kisspeptin in the hypothalamus and pituitary, suggesting that the pineal gland of female guanacos is sensitive to seasonal changes in day length. These findings also indicate a seasonal variation in the concentration of reproductive hormones, likely linked to the distinct modulation of the hypothalamic-pituitary-gonadal axis of female guanacos during short and long days. [ABSTRACT FROM AUTHOR]

Patterns of selection in South American camelids (Lamini) and their unique demographic history establish the llama and alpaca as remarkable cases of domestication among large herd animals. Skull shape is implicated in many changes reported between wild and domestic taxa. We apply 3D geometric morphometric methods to describe skull shape, form, and size, differences among the four species of Lamini. In so doing, we test if domesticated Lamini exhibit changes similar to those in other domesticated groups: not only in the skull, but also in brain and body size. In contrast to other domesticated artiodactyls, very little change has occurred in domestic alpacas and llamas compared to their wild counterparts. Nevertheless, their differences are statistically significant and include a flatter cranium, inclined palate and increased airorhynchy in the domestics. Selection pressures that contrast with those on other herd animals, as well as recent population bottlenecks, likely have influenced the morphological patterns we note in Lamini. High-resolution 3D morphospace allows skull size, shape, and form (shape + size), to discriminate all four species, with form providing the greatest separation. These results help differentiate morphologically the Lamini, which in nature are distinguished mainly by body size, and provide an additional tool to archaeologists for distinction of wild and domestic remains. Most of our shape analyses suggest a marginally closer relationship between the alpaca and vicuña, to the exclusion of the guanaco, supporting the genetic relationships for this group. The expected brain size change between wild and domestic populations is lower than previously thought, with a 15.4% reduction in llama, and 6.8% reduction in alpaca. This is the lowest reduction in brain size thus far reported among domesticated Artiodactyla. [ABSTRACT FROM AUTHOR]

Laguna Las Vegas is a high integrity and high resolution site. It is a penecontemporaneous record that was formed around 3050-3210 BP which is remarkable due to the high frequency of guanaco bones (Lama guanicoe) and, to a lesser extent, of cauquén remains (Chloephaga sp.). Additionally, a high frequency of bone pounders and chalcedony scrapers was recorded. We propose that this site was a campsite originated by an attritionally discard behavior within a short time frame, in which whole preys (guanacos) were taken for processing, consumption, and subsequent transport of their axial skeleton. The fact that cauquén remains were found suggests that human occupations took place, at least, during spring and summer. Due to these features, Laguna Las Vegas stands out as a valuable site, one which adds useful information about faunal resource management and mobility of the hunter-gatherer populations of the Coyle River middle basin. [ABSTRACT FROM AUTHOR]

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