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Herbivory is an important ecological process than has influenced the evolution of grassland-savannah systems. The evolutionary history of herbivory largely determines how resilient plant communities are to herbivory, with communities evolving with a long history generally possessing plant adaptations that make them able to cope with such disturbance. Thus, the evolutionary history of herbivory can serve as an indicator of a system's resilience to modern grazing. Determining this history, however, is problematic because quantitative measures of herbivory and knowledge of plant origin are needed over appropriate evolutionary time frames. Paleoecology offers a useful framework for assessing this evolutionary history of plant-herbivore interactions. The Patagonian steppe is a phytogeographic province of South America whose evolutionary history of herbivory has been debated. Past discussions have focused completely on the abundance of its sole large ungulate herbivore—the guanaco (Lama guanicoe Müller 1776)—since European colonization of the continent. Here we use a paleoecological approach to reconstruct the evolutionary history of herbivory and plant evolution in the Patagonian steppe over a much broader, geologic time frame (Cenozoic) to shed light on the matter. We examine the role of past climate, ancient megafauna, and guanaco in shaping the vegetation and briefly discuss how present land use may be misaligned with the steppe's evolutionary history of herbivory. • We used a paleoecological approach reconstruct the evolutionary history of herbivory in the Patagonian steppe. • Xenarthrans, which have lower metabolic requirements than other placental herbivores, characterized the ancient megafauna. • The guanaco was the sole large ungulate to inhabit the steppe after megafaunal extinction and too almost became extinct. • An arid climate characterized the Patagonian steppe well before a diversity of ungulates dispersed into South America. • Paleoecological evidence suggests the Patagonian steppe likely evolved under low herbivory and prolonged aridity. [ABSTRACT FROM AUTHOR]

The analysis of factors that determine the distribution of top‐scavengers at large scales can provide clues to understanding important ecological processes and may be useful in establishing conservation and management strategies. Here, we conducted a large‐scale survey to study the distribution of the threatened Andean Condor Vultur gryphus in relation to environmental factors in southern Patagonia. This area has undergone the settlement of livestock and the introduction of exotic wildlife, although to a lesser extent than in the distribution of Condors in northern Patagonia. The aim of this study was to determine the relevance of different factors such as the availability of food resources, the availability of suitable nesting and roosting places and the presence of humans on large‐scale condor distribution. Our results show that the presence of meadows was the primary factor shaping Andean Condor distribution, despite the fact that this habitat occupies only 4% of the Patagonian landscapes. However, this habitat has a high probability of herbivore presence, so Condors seem to optimize their searching. The availability of nesting and roosting cliffs also contributed to explaining the observed distributions. Our results suggest that Condor distribution in southern Patagonia is a compromise between the spatial locations of two low‐frequency habitats – meadows and cliffs. A successful Condor conservation strategy in southern Patagonia should include the protection of these habitats and the regulation of farming expansion, including the recovery of meadows. [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., (© 2023. BioMed Central Ltd., part of Springer Nature.)

• The presence of proactive and reactive phenotypes in female guanaco, using both physiological (cortisol) and behavioral parameters (active or passive handling avoidance) were determined. • Behavioral and physiological responses indicate a higher ability of proactive animals to cope with adverse factors than reactive group. • An assessment of coping styles could to improve the establishing of different management strategies oriented to increase animal welfare to diverse species of small ruminants in captivity. The objective of the present study was to evaluate the coping style response to handling of guanacos (Lama guanicoe) in captivity. This study contributes to a better understanding of the handling effect in captivity of the largest wild camelid of South America. Individual coping style response to handling was studied in 17 adult captive-bred guanacos. Handling was performed every 2 h for 24 h and serum cortisol concentration and behavioral responses were measured during the entire cycle of handling (12 times). Principal component analysis results showed three main factors: the first associated with reactive behavior (more immobility and escaping, less spitting) and the second and third associated with proactive behavior (more territorial control behaviors and less jumping). Nine animals were classified as reactive and eight as proactive, based on the highest component score attained. Mean cortisol concentration was 368.45 nmol/L in the reactive group and 155.96 nmol/L in the proactive group (p < 0.01). The lower levels of cortisol in the proactive group could indicate a higher ability to cope with adverse factors than the reactive group. An assessment of coping styles could improve the establishment of different management strategies oriented to increase animal welfare for diverse species of small ruminants in captivity. [ABSTRACT FROM AUTHOR]

The article discusses a study on the estimated density and population size of Lama guanicoe guanacos over major environmental gradients of Santa Cruz in southern Patagonia. Topics covered include the use of road surveys and distance sampling, spatial variation in density, and high guanaco abundance in arid lands. Also mentioned are the benefits of sustainable use of guanaco populations including rural areas' socioeconomic progress and the eventual restoration of shrub-steppes.

Abstract: The wild vicuña (Vicugna vicugna) is one of the four species of native South American camelids (SACs) in addition to the wild guanaco, and their domesticated counterparts, alpaca and llama, respectively. Serological data have indicated the presence of group A rotaviruses (RVA) specific antibodies in all 4 members of the SAC, and so far, RVA has been detected from alpacas, llamas and guanacos. A total of 59 fecal samples from healthy wild newborn and juvenile vicuñas, raised in captivity in Jujuy, Argentina were collected and analyzed by ELISA to detect RVA antigen. Two samples (3%) were found to contain G8 RVA strains and one strain (RVA/Vicuña-wt/ARG/C75/2010/G8P[14]) was selected for further genome analyses, revealing the G8-P[14]-I2-R2-C2-M2-Ax-N2-T6-E3-Hx genotype constellation. Unfortunately, no sequence data could be obtained for NSP1 and NSP5. Except for the E3 NSP4 genotype, this partial genotype constellation is reminiscent to bovine RVA strains and bovine-like RVA strains isolated from sheep, guanaco, antelope and humans. This relationship was confirmed phylogenetically, providing further evidence of the widespread presence of this genotype constellation in animals belonging to the artiodactyls. In particular, a close phylogenetic relationship was found between C75 and guanaco RVA strain RVA/Guanaco-wt/ARG/Chubut/1999/G8P[14] for at least 5 gene segments, suggesting a partial conservation of the genotype constellation of RVA strains infecting different species of SACs, even though nowadays their natural habitats are not overlapping. The further monitoring of the sanitary health of wild newborn and juvenile vicuñas is essential to improve the management practices applied in their sustainable exploitation. [Copyright &y& Elsevier]

Abstract: The concept of sociality has been associated with the effectiveness of antipredator mechanisms, like cooperative vigilance and the dilution effect. Lama guanicoe (guanaco) is a social native herbivore in South America and a social species. The objectives of this study were to evaluate the antipredator responses of different-sized groups of guanacos in areas with varying predation risks and to determine antipredator mechanisms in guanacos. For this, we measured different antipredator responses to a potential predator (human subjects). Detection of predator and flight distances from predator both increased with a greater number of guanacos per group and with greater distances among guanacos within the social group. Both buffer distance and flight time decreased with a greater number of guanacos per group, but increased with greater distances among guanacos inside the social group. Solitary adult males moved shorter distance and mixed groups moved greater distances. Flight distances were greater in areas with tall and dense vegetation than in areas with low vegetation. Buffer distance and flight time were shorter in undulating land than on flat lands, and groups were usually observed on hill slopes. Our results suggest that the benefit of social grouping in guanacos is the increased probability of avoiding predator with cooperative vigilance and not with the dilution effect. This means that a predator could be detected earlier when approaching a guanaco group than when approaching a solitary individuals and could thus be avoided. [Copyright &y& Elsevier]

Abstract: Introduction of domestic ungulates may lead to interspecific competition with native herbivores, particularly if the species involved are of similar size and share similar foraging strategies due to a scarcity of trophic resources. This interaction has not been investigated in South American deserts in which guanaco (Lama guanicoe), the larger South American wild camelid and the most widely-distributed ungulate, co-occurs with several introduced ungulates (e.g. cattle, donkeys, sheep or red deer). We studied the occurrence and abundance patterns of guanacos, donkeys and cattle in desert areas of Argentina by dung sampling. Analyses of co-occurrence show no relationship in land use between guanaco and livestock when geographical effects are removed. Distribution and abundance models of the guanaco are strongly associated with sparse plant cover, rocky substrata and human-influence variables, guanacos appearing in areas furthest from villages. Nevertheless, while guanaco distribution is weakly related to feral livestock presence, their abundance is negatively associated with donkey presence. In contrast, livestock species appear closely associated with each other, being centred on areas of densest and most productive vegetation. These results are relevant for the management of extensive arid areas of South America, where guanacos co-occur with feral donkeys and frequently conflicts with humans activities. [Copyright &y& Elsevier]

Abstract: We synthesize and discuss available isotopic data on Holocene guanaco samples from southern South America, extending from Tierra del Fuego Island to northern Patagonia and the Pampean region. We evaluate temporal and spatial tendencies on the basis of 91 samples (mainly based on δ13Ccollagen values), presenting implications for paleodietary research in archaeology. We conclude that there are no strong correlations with latitude in the macro-spatial scale, while there is a set of interesting patterns at smaller regional scales. These patterns lead us to evaluate the role of ecologic and topographic variables (e.g. canopy effect, variations in altitude, ecotones) in structuring isotopic variability. Finally, on the basis of the present analysis we suggest a number of hypotheses and perspectives for the use of stable isotopes as geographic tracers of guanaco distribution in the past, and specific implications for the paleodietary study of human samples. [Copyright &y& Elsevier]

Guanacos (Lama guanicoe) are the most important native herbivorous species in the South American steppes and the dominant ungulate in a fauna rich in rodents but poor in large mammal species. Between 2 and 4 subspecies are usually recognized within Lama guanicoe, based on subtle morphological differences and geographic distribution. To evaluate whether molecular variation is consistent with the latter hypotheses, we analyzed the complete cytochrome-b and partial control region mitochondrial DNA sequences of L. guanicoe from 22 localities in Peru, Bolivia, Argentina, and Chile. Sequence analyses of both genes support the monophyly of the species but failed to distinguish the occurrence of subspecies along the geographic range. Despite that, the northernmost populations (Peru and northern Chile) showed some degree of genetic differentiation with respect to southern representatives from Argentina, Bolivia, and rest of Chile. Analysis of genetic diversity also showed a strong signal of past low population size and a recent population expansion. [ABSTRACT FROM AUTHOR]

Focuses on the Guanacos, a modern-day South American Camelid which exist in Patagonia. Examination of the species' habits; Background on breeding and birth patterns; Identification of challenges which confront this animal; Details on th

Selective breeding of the guanaco and vicuña indisputably led to the domestic llama and alpaca. However, the place, time and process of domestication remain poorly documented, exacerbated by increased evidence of historic and recent introgression among both domestic populations, especially those involving alpaca. Here, we report the first comprehensive assessment of patterns of microsatellite variation of 13 polymorphic microsatellites in 797 individuals representing 4 species and 2 subspecies to estimate historic and ongoing patterns of gene flow. Our results confirm that llamas were domesticated almost exclusively from the northern subspecies of guanaco (Lama guanicoe cacsilensis), but cluster analyses did not support previous findings that alpacas are solely derived from the northern subspecies of vicuña (Vicugna mensalis), with some more-recent admixture with southern populations. We also confirmed continued gene flow between llama and alpaca, and found evidence for crosses between presumably feral llamas and guanacos in northern Chile. Our results highlight the need to develop and test more-accurate markers and tools for assessing the genetic heritage of individuals, to link phenotypic variation with genetic ancestry, and to conserve historic patterns of unique variation among both the wild and domestic populations. • The dominant herbivores of the arid and semi-arid habitats of South America include wild and domestic species. • The genetic and phenotypic integrity of the domestic llama and alpaca are increasingly being threatened by interbreeding. • Loss of vicuña genetic signal in alpaca is due to hybridization and introgression among South American camelids. [ABSTRACT FROM AUTHOR]

A molecular genetic protocol for distinguishing pure and hybrid South American camelids was developed to provide strong, quantifiable, and unbiased species identification. We detail the application of the approach in the context of a criminal case in the Andes Mountains of central Chile where the defendants were alleged to have illegally hunted three wild guanacos (Lama guanicoe), as opposed to hybrid domestic llama (Lama glama)/wild guanaco crosses, which are unregulated. We describe a workflow that differentiates among wild, domestic and hybrid South American camelids (Lama versus Vicugna) based on mitochondrial cytochrome b genetic variation (to distinguish between Lama and Vicugna), and MC1R and exon 4 variation of the ASIP gene (to differentiate wild from domestic species). Additionally, we infer the population origin and sex of each of the three individuals from a panel of 15 autosomal microsatellite loci and the presence or absence of the SRY gene. Our analyses strongly supported the inference that the confiscated carcasses corresponded with 2 male and 1 female guanacos that were hunted illegally. Statistical power analyses suggested that there was an extremely low probability of misidentifying domestic camelids as wild camelids (an estimated 0 % Type I error rate), or using more conservative approached a 1.17 % chance of misidentification of wild species as domestic camelids (Type II error). Our case report and methodological and analytical protocols demonstrate the power of genetic variation in coat color genes to identify hybrids between wild and domestic camelid species and highlight the utility of the approach to help combat illegal wildlife hunting and trafficking., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Members of the genus Sarcocystis (Apicomplexa: Sarcocystidae) are intracellular protozoan parasites that infect a wide range of domestic and wild animals, resulting in economic losses in production animals worldwide. Sarcocystis spp. have indirect life-cycles where canids and felids serve as main definitive hosts while a range of domestic and wild animals serve as intermediate hosts, including South American camelids (SACs) such as alpacas, llamas and guanacos. These animals primarily occur in South American countries on Andean, elevated plains but in recent years, alpacas and llamas have become emerging animal industries in other parts of the world such as Australia, Europe and the USA due to their high-quality fiber, meat and hides. For instance, alpaca meat is becoming popular in many parts of the world due to its lower cholesterol content than other red meat, thereby it has the potential of a valuable product for both local and international markets. However, SAC meat can be degraded and/or even condemned due to the presence of macroscopic sarcocysts in skeletal muscles, leading to significant economic losses to farmers. The infection is generally asymptomatic, though highly pathogenic or even fatal Sarcocystis infections have also been reported in alpacas and llamas. Despite the economic importance of sarcocystosis in SACs, little is known about the life-cycle of parasites involved, disease transmission, epidemiology, pathogenesis, diagnosis, control and public health significance. This review article provides an in-depth analysis of the existing knowledge on the taxonomy, epidemiology, clinicopathology and diagnosis of Sarcocystis in SACs, highlights knowledge gaps and proposes future areas of research that could contribute to our better understanding of sarcocystosis in these animals.

Presents information on the efforts to conserve existing guanacos in national parks in South America. Partnership of Médanos del Chaco National Park in Paraguay and Kaa-Iya del Gran Chaco National Park in Bolivia to protect the animals; Threats to the existence of guanaco; Plan of the Izoceño Indian communities for guanaco protection.