A Pliocene-Pleistocene continental biota from Venezuela

The Pliocene-Pleistocene transition in the Neotropics is poorly understood despite the major climatic changes that occurred at the onset of the Quaternary. The San Gregorio Formation, the younger unit of the Urumaco Sequence, preserves a fauna that documents this critical transition. We report stingrays, freshwater bony fishes, amphibians, crocodiles, lizards, snakes, aquatic and terrestrial turtles, and mammals. A total of 49 taxa are reported from the Vergel Member (late Pliocene) and nine taxa from the Cocuiza Member (Early Pleistocene), with 28 and 18 taxa reported for the first time in the Urumaco sequence and Venezuela, respectively. Our findings include the first fossil record of the freshwater fishes Megaleporinus, Schizodon, Amblydoras, Scorpiodoras, and the pipesnake Anilius scytale, all from Pliocene strata. The late Pliocene and Early Pleistocene ages proposed here for the Vergel and Cocuiza members, respectively, are supported by their stratigraphic position, palynology, nannoplankton, and 86 Sr/ 88 Sr dating. Mammals from the Vergel Member are associated with the first major pulse of the Great American Biotic Interchange. In contrast to the dry conditions prevailing today, the San Gregorio Formation documents mixed open grassland/forest areas surrounding permanent freshwater systems, following the isolation of the northern South American basin from western Amazonia. These findings support the hypothesis that range contraction of many taxa to their current distribution in northern South America occurred rapidly during at least the last 1.5 million years

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

New remains of Neotropical bunodont litopterns and the systematics of Megadolodinae (Mammalia: Litopterna)

ABSTRACT Litopterna is one the most diverse and long–lived clades of South American native ungulates. Megadolodus and Neodolodus are bunodont litoptern genera recorded in the middle Miocene tropical faunistic assemblage of La Venta (Colombia). Both taxa were initially identified as didolodontid ‘condylarths’, but later reclassified into Proterotheriidae, within Litopterna. Previous studies proposed their inclusion within Proterotheriidae, but possible affinities with early litopterns and didolodontids have not been properly tested in phylogenetic analyses. We report new material of Megadolodus and Neodolodus from La Venta, which document new aspects of their upper and lower dentition, and we reassess their phylogenetic relationships with Litopterna and Didolodontidae. Using pre-existing matrices, we tested two alternative approaches of character construction for serial characters on the dentition in our phylogenetic analyses. Based on previously known and new fossil material, our analyses with both coding approaches support a close relationship between Megadolodus and Neodolodus, within Litopterna, and do not support a close relationship with Didolodontidae. At a less inclusive level, the relationships of Megadolodinae within Litopterna vary depending on the coding approach used. However, all of our analyses unambiguously support the monophyly of Megadolodinae as a clade of Neotropical bunodont litopterns. While the discovery of these new remains enlightens part of the litoptern phylogeny, the sensitivity of our analyses to coding approaches further highlights the importance of critical evaluation of character construction in morphological phylogenetics. KEY WORDS: La Venta, Litopterna, Miocene, South America

Appendix 1. Stratigraphic description of ten sections and their geographical location

This file contains a detailed lithological description and geographic position of ten stratigraphic sections in the Falcón basin. These sections encompass the entire Neogene sequence

Data from: The Neogene record of northern South American native ungulates

South America was isolated during most of the Cenozoic, and it was home to an endemic fauna. The South American Native Ungulates (SANUs) exhibited high taxonomical, morphological, and ecological diversity and were widely distributed on the continent. However, most SANU fossil records come from high latitudes. This sampling bias challenges the study of their diversity dynamics and biogeography during important tectonic and biotic events, such as the Great American Biotic Interchange, the faunal exchange between North and South America after the formation of the Isthmus of Panama. We describe new SANU remains from the Neogene of the Cocinetas (northern Colombia) and Falcón (northwestern Venezuela) Basins. In the Cocinetas Basin, the middle Miocene fauna of the Castilletes Formation includes Hilarcotherium miyou sp. nov. (Astrapotheriidae), cf. Huilatherium (Leontiniidae), and Lambdaconus cf. L. colombianus (Proterotheriidae). The late Pliocene fauna of the Ware Formation includes a Toxodontinae indet. and the putative oldest record of Camelidae in South America. In the Falcón Basin, the Pliocene/Pleistocene faunas of the Codore and San Gregorio Formations include Falcontoxodon aguilerai gen. et sp. nov. and Proterotheriidae indet. We provide a phylogenetic analysis for Astrapotheriidae and Toxodontidae. The new data document a low-latitude provinciality within some SANU clades (e.g., Astrapotheriidae, Leontiniidae) during the middle Miocene. This contrasts with the wide latitudinal distribution of clades of other mammals recorded in the fauna, including the sparassodont Lycopsis padillai, the sloth Hyperleptus, and the proterotheriid Lambdaconus cf. L. colombianus

Data from: The Neogene record of northern South American native ungulates

South America was isolated during most of the Cenozoic, and it was home to an endemic fauna. The South American Native Ungulates (SANUs) exhibited high taxonomical, morphological, and ecological diversity and were widely distributed on the continent. However, most SANU fossil records come from high latitudes. This sampling bias challenges the study of their diversity dynamics and biogeography during important tectonic and biotic events, such as the Great American Biotic Interchange, the faunal exchange between North and South America after the formation of the Isthmus of Panama. We describe new SANU remains from the Neogene of the Cocinetas (northern Colombia) and Falcón (northwestern Venezuela) Basins. In the Cocinetas Basin, the middle Miocene fauna of the Castilletes Formation includes Hilarcotherium miyou sp. nov. (Astrapotheriidae), cf. Huilatherium (Leontiniidae), and Lambdaconus cf. L. colombianus (Proterotheriidae). The late Pliocene fauna of the Ware Formation includes a Toxodontinae indet. and the putative oldest record of Camelidae in South America. In the Falcón Basin, the Pliocene/Pleistocene faunas of the Codore and San Gregorio Formations include Falcontoxodon aguilerai gen. et sp. nov. and Proterotheriidae indet. We provide a phylogenetic analysis for Astrapotheriidae and Toxodontidae. The new data document a low-latitude provinciality within some SANU clades (e.g., Astrapotheriidae, Leontiniidae) during the middle Miocene. This contrasts with the wide latitudinal distribution of clades of other mammals recorded in the fauna, including the sparassodont Lycopsis padillai, the sloth Hyperleptus, and the proterotheriid Lambdaconus cf. L. colombianus

Appendix 3. Character-taxon matrix used in the phylogenetic analysis of Astrapotheriidae

Nexus file with the annotated character-taxon matrix used in the phylogenetic analysis of Astrapotheriidae. It includes the commands use in the analysis with PAU

Appendix 4. Character-taxon matrix used in the phylogenetic analysis of Toxodontidae.

Nexus file with the annotated character-taxon matrix used in the phylogenetic analysis of Toxodontidae. It includes the commands for the analysis in PAUP under equal weight