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[Display omitted] • Digenean alter host growth, survival, reproduction and behavior. • Ecological studies on digenean-mollusk systems in South America are in early stages. • Digenean community analysis needs diversity indices. • Studying digenean-mollusk systems in South America shows great promise. The study of digeneans and their association with mollusks commenced in Europe and South America during the mid-19th to early 20th centuries. Digenean infestation can severely degrade host tissue, leading to diminished energy resources and eventual host mortality. However, these parasites can also induce various non-lethal effects, including changes in growth rates, survival rates, and reproductive capabilities, alongside physiological and behavioral alterations. While numerous studies have explored the ecological effects of digeneans on hosts in Europe and North America, our understanding of these dynamics in South America, particularly in first intermediate hosts, remains limited. Therefore, this paper aims to provide an overview of ecological investigations into digenean-mollusk systems in South America, emphasizing the importance of robust sampling designs and statistical analyses to address key ecological inquiries. Although fascinating examples exist of parasitism influencing different hierarchical levels of digenean-mollusk systems, particularly at the individual, population, and community levels, documentation of their ecosystem-level impacts is comparatively sparse. As South American studies of digenean-mollusk systems from an ecological perspective are still in their early stages, there is immense potential for uncovering unique ecological patterns in this largely unexplored region, propelling us toward further developmental strides in the parasite ecology. [ABSTRACT FROM AUTHOR]

• Classical weed biological control is hardly practiced in Argentina today. • There is a small community of local experts that work mostly for overseas projects. • The National Strategy on Invasive Alien Species promotes biocontrol initiatives. • A prioritization process is developed to select the best target(s) for biocontrol. • Public awareness and outreach activities could help gain biocontrol public support. Argentina hosted pioneering classical weed biological control projects that were carried out by state institutions between the 1970s and 1990s, at a time when the practice was almost unheard of in Latin America. Despite the early development of these initiatives, the discipline did not prosper and all projects were discontinued. Notwithstanding, Argentina continued to provide biological control agents for the control of weeds in many other parts of the world, ensuring the expertise persisted. Although public concern about invasive plants and chemical-dependent agricultural practices has increased over time, it did not lead to a greater acceptance of classical biological control of weeds, which is still regarded with mistrust or ignored in many public and academic circles alike. Furthermore, there are no systems in place to reach a consensus on declaring weeds as targets for biological control in Argentina. In this paper we discuss different ways in which the community of researchers working in the field in Argentina can help relaunch the biological control of weeds, including the preparation of a prioritized list of target species. A list of this kind would not only reduce costs, but also help in developing trust in the discipline of biological control informing regulators and decision makers in this regard. Prospects are brighter today than a few years ago, but considerable communication and educational work on the benefits of this practice is still required to gain more support before it can effectively be re-implemented. [ABSTRACT FROM AUTHOR]

• The population trend of late Pleistocene-Holocene hunter-gatherers changed its trajectory ca. 2,300 cal years BP coincident with the adoption of domesticates. • After 2,300 cal years BP, a significant increase in human population occurred. We observe population increases ("booms") followed by notable drops ("busts"). • Stable isotope (ẟ13C) on human bone follow a similar trend, indicating an increased consumption of maize during the "boom" periods and a decreased consumption during the "bust" periods. • We propose that human population changes during the last 2,300 cal years BP correlate with levels of maize consumption. This paper explores the relationships between population change and human diet after the adoption of domesticated resources in northwest Mendoza, a subregion of central western Argentina (CWA). To estimate population, we used summed probability distributions of radiocarbon ages (RC-SPD). We used carbon and nitrogen stable isotope values (ẟ13C co , ẟ13C ca , and ẟ15N) obtained on human bone (collagen and carbonate) to reconstruct human diet. The population trend of late Pleistocene-Holocene hunter-gatherers changed its trajectory ca. 2300 cal years BP coincident with the adoption of domesticates. After this date, a significant increase in human population occurred. We observe population increases ("booms") followed by notable drops ("busts"). Stable isotopes (ẟ13C) on human bone follow a similar trend, indicating an increased consumption of maize during the "boom" periods and a decreased consumption during the "bust" periods. Based on the association between estimated changes in human population and changes in human bone isotope values over the last 2300 cal years BP, we propose that levels of maize consumption emerge from human predator–prey and plant-herbivore interactions. The use of maize, thus, is not part of a social evolutionary stage, but, rather, an outcome of continuous social-ecological process in which maize use may increase or decrease over time. [ABSTRACT FROM AUTHOR]

• Six obsidian sources increased their use in the Late Holocene in north Patagonia. • The closer source to Diamante Valley, is the least used. • The best quality source, Las Cargas, was the most used across the Late Holocene. • Obsidian helped to minimize risk in the occupation of high elevation locations. • Obsidian exchange routes may find a pattern in least cost path analysis results. • Exchange of obsidian followed routes through High elevations villages to sources. In this paper we explore obsidian conveyance in the Diamante Valley, in northwestern Patagonia, Argentina. Obsidian is the third most-common toolstone used in the Diamante Valley after basalts and local cryptocrystallines. Obsidian artifacts are predominantly projectile points and bifaces, with few cores and early-stage reduction debris. To explain these patterns, we conducted XRF sourcing and technological analysis of 177 obsidian artifacts collected there. We also conducted a GIS-based least cost path analysis to assess the costs of conveying obsidian from sources to sites in the Diamante watershed. We found that hunter-gatherers used Las Cargas as the principal obsidian source, followed by Maule 1 and 2, El Peceño, and Coche Quemado. The nearest source, Laguna del Diamante, was the least used. These data, combined with an analysis of the ways cores, formed tools, and debitage types were conveyed and ultimately deposited at sites in the Diamante watershed, suggest a late Holocene pattern of highland-oriented indirect access, implying highland village sites likely served as nodes in a regional and extraregional exchange network focused not only on obsidian but also on other goods, information, and social obligations. [ABSTRACT FROM AUTHOR]

[Display omitted] • We infer the largest phylogeny of Leptophis to date. • Widespread Leptophis ahaetulla sensu lato is composed of multiple species. • Species within L. ahaetulla have evolved distinct color patterns. • Widespread L. depressirostris possibly contains two species. Tetrapod taxa with broad geographic distributions across the Neotropics are often composed of multiple evolutionary lineages. In this paper, we present the most complete phylogeny of Leptophis to date and assess morphology-based species limits within the broadly distributed green parrot snake Leptophis ahaetulla sensu lato, which occurs from Mexico to Argentina. Although L. ahaetulla sensu stricto, L. nigromarginatus and L. occidentalis were recovered as paraphyletic, tree topology tests failed to reject their monophyly. Monophyly of L. bocourti , L. coeruleodorsus , L. cupreus , L. depressirostris , L. marginatus , L. riveti and L. sp. nov. was strongly supported. Our phylogenetic trees support recognition of multiple species within Leptophis ahaetulla sensu lato and suggest that color evolution and the uplift of the Andes played an important role in the diversification of parrot snakes. [ABSTRACT FROM AUTHOR]