Article
Environmental Sciences
Keilor Rojas-Jimenez, Fresia Villalobos-Rojas, Johan Gatgens-Garcia, Marco Rodriguez-Arias, Natalia Hernandez-Montero, Ingo S. Wehrtmann
Summary: This study reveals the presence of microplastics (MPs) in bivalve species in the Central America's Pacific region, with some species having a prevalence rate of 100%. On average, each individual contained 4.8 microplastic fragments and 2.1 items in wet tissue. Fibers constituted the majority of microplastic composition.
MARINE POLLUTION BULLETIN
(2022)
Article
Water Resources
Alejandro Basaldua, Emiliano Alcaraz, Mauricio Quiroz-Londono, Cristina Dapena, Eduardo Ibarra, Camilo Velez-Agudelo, Lorenzo Copia, Daniel Martinez
Summary: Tritium is an ideal tracer for groundwater and surface dating, but its records in precipitation are often sparse. By comparing different reconstruction methods, tritium time series curves were obtained for the temperate zone of South America, which can be used as representative input curves for future studies.
HYDROLOGICAL PROCESSES
(2022)
Article
Geosciences, Multidisciplinary
Roland Freisleben, Julius Jara-Munoz, Daniel Melnick, Jose Miguel Martinez, Manfred R. Strecker
Summary: Tectonically active coasts are characterized by multiple marine terraces formed by a combination of wave erosion, tectonic uplift, and sea-level oscillations. Our study of the marine terraces along the western coast of South America revealed a median elevation of 30.1 m, suggesting a median uplift rate of 0.22 m kyr(-1) over the past approximately 125 kyr. The patterns of terrace elevation and uplift rate exhibit different structures along the coast, with long-wavelength deformation possibly being controlled by deep-seated processes like subduction, while short-wavelength deformation may be associated with crustal faulting.
EARTH SYSTEM SCIENCE DATA
(2021)
Article
Geochemistry & Geophysics
Roland Freisleben, Julius Jara-Munoz, Daniel Melnick, Diego Molina, Andres Tassara, Peter van der Beek, Manfred R. Strecker
Summary: This study investigates the mechanisms driving permanent coastal uplift in the tectonically active South American margin. By analyzing uplifted marine terraces and tectonic parameters, the researchers identify a constant background-uplift rate along the margin, perturbed by changes at variable wavelengths. The study suggests that major, deep earthquakes near the Moho are responsible for the moderate, long-term background uplift, while accumulation of permanent deformation over millennial time scales occurs through multiple, distinct uplift phases. The findings highlight the utility of a signal-analysis approach in understanding surface deformation in subduction zones at a continental scale.
Article
Environmental Sciences
Nelson Rangel-Buitrago, Felipe Lamus Ochoa, Ruben Dario Beltran Rodriguez, Jose Brito Moreno, Jorge Trilleras, Victoria Andrea Arana, William J. Neal
Summary: This study reports the discovery of plastics in the geological record along the central Caribbean Coast of Colombia. Different types of plastics, including rocks, altered plastics, soils, and artifacts were identified and analyzed using FTIR spectroscopy. The research sheds light on the petrology of these emerging forms of pollution, caused primarily by human activities, and highlights the urgent need to control or eliminate plastic use to mitigate its overwhelming impact on natural environments globally.
MARINE POLLUTION BULLETIN
(2023)
Article
Geosciences, Multidisciplinary
Daniel R. Muhs
Summary: This passage mainly introduces the records of MIS 5e coastal terraces and coral reef terraces along the Pacific coast of North America, as well as the results of related chronostratigraphic studies. The shoreline angle is the primary indicator of paleo-sea level during MIS 5e, and chronology is determined mainly through uranium-series ages and amino acid ratios. The passage also mentions that sea surface temperatures were higher during MIS 5e compared to present, and there was no wholesale shift in faunal provinces. The tectonic activity in the region and the glacial isostatic adjustment processes contributed to the high sea stands during MIS 5e. Additionally, it introduces the records of earlier interglacial periods and the cooling trend during MIS 5a.
EARTH SYSTEM SCIENCE DATA
(2022)
Article
Ecology
Alejandro Perez-Matus, Philipp Neubauer, Jeffrey S. Shima, Marcelo M. Rivadeneira
Summary: Patterns of species richness and functional diversity in temperate reef fish communities in the South Pacific were investigated across different spatial scales. The study found that species richness declined from west to east across the region, but this pattern was only detectable at larger scales. The study also revealed that functional diversity varied differently from species richness and was dependent on the spatial scale of analysis. Additionally, different provinces had distinct functional components within their reef fish communities.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Environmental Sciences
Gabriel Enrique De-la-Torre, Carlos Ivan Pizarro-Ortega, Diana Carolina Dioses-Salinas, Md. Refat Jahan Rakib, Williams Ramos, Victor Pretell, Victor Vasques Ribeiro, Italo Braga Castro, Sina Dobaradaran
Summary: Beaches in the Anthropocene are burdened with human-derived pollution, with new forms of plastic formations being described and documented, including plasticrusts, plastiglomerates, and pyroplastics. The study in Peru provided evidence of these formations and suggested a new plasticrust formation pathway based on plastic burning and filling of rock crevices with molten plastic.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Geography, Physical
P. Strobel, M. Bliedtner, A. S. Carr, J. Struck, N. du Plessis, B. Glaser, M. E. Meadows, L. J. Quick, M. Zech, R. Zech, T. Haberzettl
Summary: This study presents a paleoenvironmental record from Vankervelsvlei in South Africa and analyzes the Late Quaternary climate changes in the region. The study reveals dry and moist conditions over the past 250,000 years, influenced by the source and seasonality of precipitation. The findings provide important insights into the hydrological balance and climate evolution of the southern Cape coastal region.
QUATERNARY SCIENCE REVIEWS
(2022)
Article
Multidisciplinary Sciences
Aaron Kornbluth, Bryce D. Perog, Samantha Crippen, Danielle Zacherl, Brandon Quintana, Edwin D. Grosholz, Kerstin Wasson
Summary: In order to conserve coastal foundation species, the distribution and abundance patterns of native Olympia oysters and non-native Pacific oysters along the west coast of North America were studied. An interactive web-based map was created to visualize the spatial and temporal patterns of the oysters. The study found a significant decrease in abundance and distribution of native Olympia oysters, while the non-native Pacific oysters significantly increased. Restoration of habitat and increase in abundance of native oysters were recommended, as well as restoration of natural biogenic beds on mudflats and sandflats, particularly in the southern range.
Article
Biochemistry & Molecular Biology
Megan Ruffley, Megan L. Smith, Anahi Espindola, Daniel F. Turck, Niels Mitchell, Bryan Carstens, Jack Sullivan, David C. Tank
Summary: The disjunct temperate rainforests in the Pacific Northwest of North America are characterized by two dominant tree species, western redcedar and western hemlock. The demographic histories of these species have been influenced by geological and climatic changes over the last 5 million years, including glaciations. Genomic data analysis reveals that both inland and coastal populations of these species diverged around 2.5 million years ago and experienced population size changes during glacial cycles. Importantly, there was evidence of gene flow between coastal and inland populations during the mid-Holocene.
Article
Geosciences, Multidisciplinary
Fernando E. Lopez, Cintia Kaufmann, Juan M. Drovandi, Osvaldo A. Conde, Alejandro R. Braeckman, Jonatan A. Arnol, Lautaro Estrada, Fernando Pedernera, Ulises Abarca
Summary: This study presents the first discovery of Pridolian graptolite assemblage in the Eastern Precordillera of San Juan Province, Argentina, which is the first occurrence in South America. Two graptolite taxa, Skalograptus parultimus and cf. Enigmagraptus, were identified for the first time in South America. This finding is significant for the understanding of graptolite research and the Pridolian period in South America.
Article
Environmental Sciences
Remya Bhaskaran, Krupesha Sharma Sulumane Ramachandra, Reynold Peter, Sumithra Thangalazhy Gopakumar, Mini Kalappurakkal Gopalan, Rithin Raj Mozhikulangara
Summary: Vibrio parahaemolyticus is a pathogenic bacterium that poses a threat to both humans and aquatic organisms. It is commonly found in estuaries and oceans. A study on bivalve-associated V. parahaemolyticus showed that the bacterial abundance was higher in the post-monsoon season compared to the monsoon season. The bacterium exhibited high antimicrobial resistance, particularly against ampicillin. Plasmid-associated antimicrobial resistant genes were prevalent in the aquatic environment. Additionally, certain bacteria showed the potential to inhibit the growth of V. parahaemolyticus.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Multidisciplinary Sciences
Adam P. Rorabaugh
Summary: Recent developments in radiocarbon dating have allowed archaeologists to re-examine population dynamics in the Salish Sea region. This study builds upon previous research by Taylor et al. (2011) and utilizes Kernel Density Estimation (KDE) with an extended data set of 538 radiocarbon dates. Findings indicate a period of population growth in the coastal Northwestern Washington from 3200-2800 cal BP, as well as in the San Juan islands from 2600-2200 cal BP. The study also suggests shifts in the use of the San Juan Islands and a peak in large-scale occupation from 650-300 cal BP.
Article
Biology
Matias Javier Peralta, Brenda Soledad Ferrero
Summary: This article reports and describes the first fossil of a blind snake found in Argentina. The fossil, an Epictia sp. (Leptotyphlopidae) vertebra, was discovered in the basal layer of an Early Holocene fluvial unit in the province of Entre Rios, northeastern Argentina. This fossil contributes to the knowledge of the fossil record in South America and represents one of the few documented fossils from the Southern Hemisphere. Additionally, it provides new insights into the trunk vertebral morphology of Argentinian species in the Leptotyphlopidae family.
HISTORICAL BIOLOGY
(2023)
Article
Environmental Sciences
Valeria Hidalgo-Ruz, Guillermo Luna-Jorquera, Marcus Eriksen, Hanna Frick, Diego Miranda-Urbina, Matias Portflitt-Toro, Marcelo M. Rivadeneira, Christopher J. R. Robertson, R. Paul Scofield, Juan Serratosa, Cristian G. Suazo, Martin Thiel
Summary: The study reveals that the composition of floating plastics from terrestrial sources changes during transport with oceanic currents, reducing the proportion of prey-like plastics in subtropical gyres. The stomach contents of surface-feeding and diving seabirds are dominated by hard, white/grey, and round plastic items, similar to plastics from the South Pacific Gyre, indicating non-selective ingestion. Nesting areas show a more variable composition of brightly colored plastics, suggesting selective removal of plastics by seabirds, possibly from oceanic sources.
AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS
(2021)
Article
Ecology
Patricio Hernaez, Phillip B. Fenberg, Marcelo M. Rivadeneira
Summary: Although burrowing shrimps show an increasing diversity towards the tropics, there are departures from the idealized LDG, with asymmetries between hemispheres and bimodal distribution within the tropics. Environmental variables such as bottom seawater temperature, salinity, and tidal range play significant roles in influencing species richness, emphasizing the importance of ecophysiological constraints in shaping the LDG pattern.
JOURNAL OF BIOGEOGRAPHY
(2021)
Article
Geochemistry & Geophysics
Jordon Bright, Chris Ebert, Matthew A. Kosnik, John R. Southon, Katherine Whitacre, Paolo G. Albano, Carola Flores, Thomas K. Frazer, Quan Hua, Michal Kowalewski, Julieta C. Martinelli, David Oakley, Wesley G. Parker, Michael Retelle, Matias do Nascimento Ritter, Marcelo M. Rivadeneira, Daniele Scarponi, Yurena Yanes, Martin Zuschin, Darrell S. Kaufman
Summary: The study compared the results of direct carbonate and standard graphite C-14 determinations, finding that there was no significant difference in the majority of samples, although variation in direct carbonate pMC values was underestimated. Direct carbonate C-14 dating was shown to be a cost-effective and efficient complement to standard graphite C-14 dating.
Article
Paleontology
Maurice Guicharrousse-Vargas, Jaime A. Villafana, Jorge D. Carrillo-Briceno, Pablo Oyanadel-Urbina, Romina Figueroa, Jose R. Perez-Marin, Marcelo M. Rivadeneira, Jurgen Kriwet
Summary: This study presents the first fossil record of the sawshark genus Pliotrema from the south-eastern Pacific Ocean, specifically from a little-known fossil locality named Arenas de Caldera in the Atacama Region of Chile. The fossiliferous deposits are likely from the middle Miocene to early Pliocene Bahia Inglesa Formation. The absence of extant species of this sawfish in the eastern Pacific is attributed to cooling conditions during the Neogene.
Article
Paleontology
Pablo Oyanadel-Urbina, Carlos De Gracia, Jorge D. Carrillo-Briceno, Sven N. Nielsen, Hector Flores, Victor Casteletto, Juergen Kriwet, Marcelo M. Rivadeneira, Jaime A. Villafana
Summary: Despite being rich in marine fossil vertebrates, the Bahia Inglesa Formation along the Pacific coast of Chile had not been thoroughly studied for bony fishes until this research was conducted. By revising historical collections, 27 fossil remains of bony fishes were described, revealing new fossil records for various taxa. The study indicates that the fish fauna from the Bahia Inglesa Formation likely lived at depths ranging from 98 to 382 meters, with a mean depth of 252 meters, and shows low taxonomic similarity with other Neogene geological units in the southeast Pacific Ocean.
Article
Behavioral Sciences
Patricio Hernaez, Erick Villegas-Castro, Marcio Camargo Araujo Joao, Rafael Campos Duarte, Marcelo M. Rivadeneira
Summary: Burrowing shrimps, such as Lepidophthalmus bocourti, show complex social structures with solitary individuals as well as homosexual and heterosexual pairs and trios. These shrimps exhibit notable sexual dimorphism in both body size and cheliped size, with female-female and male-female-female associations possibly stable over time.
BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY
(2021)
Article
Environmental Sciences
Jorge Avaria-Llautureo, Chris Venditti, Marcelo M. Rivadeneira, Oscar Inostroza-Michael, Reinaldo J. Rivera, Cristian E. Hernandez, Cristian B. Canales-Aguirre
Summary: Using phylogenetic methods, research has found that smaller clupeiform fish are historically found in warmer waters, move at slower speeds, and have lower speciation rates. Fish move faster and evolve quicker under rapid temperature changes, but historical rates are much lower than current warming rates.
NATURE CLIMATE CHANGE
(2021)
Article
Environmental Sciences
Carlos Lara, Gonzalo S. Saldias, Bernard Cazelles, Marcelo M. Rivadeneira, Richard Munoz, Alexander Galan, Alvaro L. Paredes, Pablo Fierro, Bernardo R. Broitman
Summary: This study utilized 19 years of remote sensing data to analyze the effects of climatic variability on terrestrial vegetation in six protected areas of southwestern South America. The results showed that different climate oscillations had varying impacts on phenological activity of vegetation at different latitudes. Further long-term studies are needed to improve our understanding of the influence of climate change on vegetation condition and phenological variability in the region.
Article
Psychology, Clinical
Joucelyn Rivadeneira-Valenzuela, Marcelo M. Rivadeneira
Summary: The study validated the applicability of the Family Strengths Scale in the Chilean population, showing associations with family self-efficacy and family adaptation. The scale demonstrated high reliability values and could guide interventions to enhance family strengths and protective resources, improving the quality of family life.
ACTA COLOMBIANA DE PSICOLOGIA
(2021)
Article
Multidisciplinary Sciences
Rodrigo A. Moreno, Fabio A. Labra, Darko D. Cotoras, Patricio A. Camus, Dimitri Gutierrez, Luis Aguirre, Nicolas Rozbaczylo, Elie Poulin, Nelson A. Lagos, Daniel Zamorano, Marcelo M. Rivadeneira
Summary: The study found that there is a rare hump-shaped latitudinal diversity gradient among marine organisms along the Southeastern Pacific coast, with species richness peaking at around 42 degrees south and declining towards the northern and southern areas. There is a significant increase in phylogenetic conservatism and species richness towards the southern region, while pairwise distance variation shows the opposite trend. This suggests that evolutionary processes play a major role in shaping the latitudinal diversity gradient in this region.
Article
Ecology
Alejandro Perez-Matus, Philipp Neubauer, Jeffrey S. Shima, Marcelo M. Rivadeneira
Summary: Patterns of species richness and functional diversity in temperate reef fish communities in the South Pacific were investigated across different spatial scales. The study found that species richness declined from west to east across the region, but this pattern was only detectable at larger scales. The study also revealed that functional diversity varied differently from species richness and was dependent on the spatial scale of analysis. Additionally, different provinces had distinct functional components within their reef fish communities.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Geology
J. C. Martinelli, C. S. Ruz, A. Perez-Matus, M. M. Rivadeneira
Summary: Drill holes are used as quantitative tools to calculate predation frequencies and provide information about predator preference and strategies. This study used drill hole information to characterize the predatory habits of muricid gastropods in Chile. The results revealed the specific predatory strategies of different species and the consistency of their behavior in both experiments and death assemblages.
Article
Environmental Sciences
Marcelo M. Rivadeneira, Sven N. Nielsen
Summary: The Humboldt Current Marine Ecosystem (HCE) is facing a significant threat to marine biodiversity, particularly from overfishing. This study uses the Quaternary fossil record along the HCE coast to assess the impact of human activities on mollusk diversity. The results show that modern mollusk assemblages have undergone drastic alterations compared to fossil counterparts, with significant changes in species composition and a reduction in the relative abundance of exploited species. This study highlights the long-term disruption of species composition and the severe disturbance caused by overfishing, providing a foundation for understanding the impacts of anthropogenic stressors in the HCE.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Biodiversity Conservation
Mariana Grossmann, Sven N. Nielsen, Marcelo M. Rivadeneira, Nelson Valdivia
Summary: Understanding latitudinal variations in biodiversity is essential for biogeography. In the coast of the Southeast Pacific, it is observed that several taxa exhibit increasing species numbers from lower to higher latitudes. This phenomenon can be explained by the presence of fjords formed during glaciations, which increased the diversity of available biotopes and allowed higher diversity in high latitudes. This research focuses on analyzing latitudinal patterns of functional diversity in the fossil record before the formation of fjords in order to assess this hypothesis.
Article
Biodiversity Conservation
Jaime A. A. Villafana, Marcelo M. M. Rivadeneira, Catalina Pimiento, Juergen Kriwet
Summary: This study provides a summary of the rich fossil record of Neogene chondrichthyans in Europe and investigates the processes that led to their current diversity and geographical distribution. The results show that the number of chondrichthyan genera increased in the early Miocene and then decreased in the Paratethys during the middle Miocene. The study also reveals the influence of global and regional climatic events on the origination and extinction rates of these species.
