Collaborative Research: Understanding the Evolution of High-latitude Permo-Triassic Paleoenvironments and their Vertebrate Communities.

大约2.52亿年前，地球上90%以上的物种灭绝。与这次灭绝同时发生的是，盘古大陆的南极部分气候变暖，冰川消失。人们对南极洲大灭绝的幸存者知之甚少，尽管有人猜测，南极洲的高纬度地理位置使它免受大灭绝最严重影响的影响。沙克尔顿冰川地区是研究南极洲这次灭绝的最佳地点，因为它暴露了大量正确年代的岩石和20世纪60年代和80年代在那里发现的相关化石。在这项研究中，古生物学家将研究大约2.6亿到2.4亿年前的脊椎动物化石，以了解高纬度地区的生命是如何在巨大的气候变化面前进化的。此外，地质学家将使用化石土壤和化石植物物质更精确地重建南极洲在这一灭绝边界上的气候。这些数据将使我们更全面地了解古代气候，以及南极的生命与低纬度地区的生命相比如何。本科生和研究生将积极参与这项研究。公众对南极科学的参与将在几个自然历史博物馆完成。这个为期三年的项目将通过在南极洲沙克尔顿冰川地区进行实地考察，研究二叠纪-三叠纪古环境及其脊椎动物群落的演变。该团队将描述沙克尔顿地区地层中的二叠纪-三叠纪边界，并将其与该地区其他地层序列相关联（例如，通过化石植物有机质的稳定碳同位素地层）。研究人员将使用多种类型的数据来评估古环境，包括：1)古土壤形态；2)古土壤地球化学；3)成土有机质；4)化石木材年代学和稳定同位素。南极洲的fremow组保存了整个三叠纪最高古纬度（~70°S）的四足动物群，因此有可能为研究中生代早期极地生物的进化提供重要的线索。来自南极洲的三叠纪脊椎动物的生物学将通过分析骨骼和象牙的生长组织学，与来自低古纬度的同种脊椎动物进行比较。在沙克尔顿冰川地区的巴克利和弗雷莫地层保存的高纬度地层背景下，将采用跨学科的方法来解决环境变化、动物组成和生物地理模式之间的关系。

Around 252 million years ago, a major mass extinction wiped out upwards of 90% of species on Earth. Coincident with this extinction, the Antarctic portion of the supercontinent of Pangea transitioned to a warmer climatic regime and became devoid of glaciers. Little is known about the survivors of the extinction in Antarctica, although it has been hypothesized that the continent's high latitude location shielded it from the worst of the extinction's effects. The Shackleton Glacier region is the best place to study this extinction in Antarctica because it exposes an abundance of correct age rocks and relevant fossils were found there in the 1960s and 1980s. For this research, paleontologists will study fossil vertebrates that span from about 260 to 240 million years ago to understand how life evolved at high latitudes in the face of massive climate change. In addition, geologists will use fossil soils and fossil plant matter to more precisely reconstruct the climate of Antarctica across this extinction boundary. These data will allow for a more complete understanding of ancient climates and how Antarctic life compared to that at lower latitudes. Undergraduate and graduate students will be actively involved in this research. Public engagement in Antarctic science will be accomplished at several natural history museums.This three-year project will examine the evolution of Permo-Triassic paleoenvironments and their vertebrate communities by conducting fieldwork in the Shackleton Glacier region of Antarctica. The team will characterize the Permo-Triassic boundary within Shackleton area strata and correlate it to other stratigraphic successions in the region (e.g. via stable carbon isotope stratigraphy of fossilized plant organic matter). The researchers will use multiple types of data to assess the paleoenvironment, including: 1) paleosol morphology; 2) paleosol geochemistry; 3) pedogenic organic matter; and 4) fossil wood chronology and stable isotopes. The Fremouw Formation of Antarctica preserves the highest paleolatitude (~70° S) tetrapod fauna of the entire Triassic and thus has the potential to shed important light on the evolution of polar life during the early Mesozoic. The biology of Triassic vertebrates from Antarctica will be compared to conspecifics from lower paleolatitudes through analysis of growth in bone and tusk histology. An interdisciplinary approach will be used to address relationships between environmental change, faunal composition, and biogeographic patterns in the context of the high-latitude strata preserved in the Buckley and Fremouw formations in the Shackleton Glacier region.