Eocene shark teeth from peninsular Antarctica: Windows to habitat use and paleoceanography

Eocene climate cooling, driven by the falling pCO2 and tectonic changes in the Southern Ocean, impacted marine ecosystems. Sharks in high-latitude oceans, sensitive to these changes, offer insights into both environmental shifts and biological responses, yet few paleoecological studies exist. The Middle-to-Late Eocene units on Seymour Island, Antarctica, provide a rich, diverse fossil record, including sharks. We analyzed the oxygen isotope composition of phosphate from shark tooth bioapatite (δ18Op) and compared our results to co-occurring bivalves and predictions from an isotope-enabled global climate model to investigate habitat use and environmental conditions. Bulk δ18Op values (mean 22.0 ± 1.3‰) show no significant changes through the Eocene. Furthermore, the variation in bulk δ18Op values often exceeds that in simulated seasonal and regional values. Pelagic and benthic sharks exhibit similar δ18Op values across units but are offset relative to bivalve and modeled values. Some tax..., See methods in Larocca Conte, G., Aleksinski, A., Liao, A., Kriwet, J., Mörs, T., Trayler, R. B., Ivany, L. C., Huber, M., Kim, S. L. (2024). Eocene Shark Teeth From Peninsular Antarctica: Windows to Habitat Use and Paleoceanography. Paleoceanography and Paleoclimatology, 39, e2024PA004965., , # Data from: Eocene Shark Teeth from Peninsular Antarctica: Windows to Habitat Use and Paleoceanography. [https://doi.org/10.5061/dryad.qz612jmq2](https://doi.org/10.5061/dryad.qz612jmq2) The repository folder includes scripts and spreadsheets for phosphate oxygen stable isotope (δ18Op) analysis measured from shark tooth biogenic apatite collected from the Eocene deposits of the La Meseta and Submeseta formations (West Antarctica, Seymour Island). It also contains Fourier-Transform Infrared Spectroscopy (FTIR) analysis, a Bayesian model for temperature estimates, and model output extraction scripts from the iCESM simulation for the Early Eocene (Zhu et al., 2020). Scripts and data are stored in specific folders on the type of analysis. All scripts are in R or Python language.   **Usage notes** **1 \"iCESM modeling scripts\" directory** The folder includes scripts in Jupiter Notebook format for extracting and plotting iCESM seawater outputs for the Eocene. The folder includes two fil...受大气二氧化碳分压（pCO₂）下降与南大洋构造变化共同驱动的始新世气候变冷，对海洋生态系统造成了显著影响。高纬度海域的鲨鱼对这类环境变化极为敏感，可为我们揭示环境变迁与生物响应机制提供关键线索，但目前相关古生态学研究仍较为匮乏。南极洲西摩岛的中-晚始新世地层保存了丰富多样的化石记录，其中便包含鲨鱼化石。本研究对鲨鱼牙齿生物磷灰石中的磷酸盐氧同位素组成（δ¹⁸Oₚ）进行了分析，并将所得结果与同期产出的双壳类数据以及同位素耦合全球气候模型的预测结果进行对比，以探讨鲨鱼的栖息地利用模式与古海洋环境状况。整体磷酸盐氧同位素组成（δ¹⁸Oₚ）的平均值为22.0 ± 1.3‰，在整个始新世时期未出现显著变化。此外，整体δ¹⁸Oₚ值的波动幅度往往高于模型模拟得到的季节与区域波动范围。不同地层中的远洋与底栖鲨鱼展现出相似的δ¹⁸Oₚ值，但相较于双壳类数据与模型模拟结果，存在系统性偏移。部分分类学内容详见参考文献：Larocca Conte, G., Aleksinski, A., Liao, A., Kriwet, J., Mörs, T., Trayler, R. B., Ivany, L. C., Huber, M., Kim, S. L. (2024). 南极半岛始新世鲨鱼牙齿：栖息地利用与古海洋学研究窗口. 《古海洋学与古气候学》, 39, e2024PA004965. # 数据集来源：《南极半岛始新世鲨鱼牙齿：栖息地利用与古海洋学研究窗口》 数据集DOI：10.5061/dryad.qz612jmq2 本数据集仓库包含针对采自南极洲西部西摩岛拉梅塞塔组与苏布梅塔组始新世地层中鲨鱼牙齿生物磷灰石的磷酸盐稳定氧同位素（δ¹⁸Oₚ）分析所需的脚本与电子表格。此外，仓库还涵盖傅里叶变换红外光谱（Fourier-Transform Infrared Spectroscopy, FTIR）分析数据、用于温度估算的贝叶斯模型，以及针对早始新世iCESM模拟结果的模型输出提取脚本（Zhu等，2020）。所有脚本与数据按照分析类型分别存储于对应文件夹中，所有脚本均采用R或Python语言编写。 **使用说明** **1. "iCESM modeling scripts"目录** 该文件夹包含以Jupiter Notebook格式编写的脚本，用于提取并绘制始新世时期iCESM模拟的海水数据。本文件夹包含两个……