COLLABORATIVE RESEARCH: SNAPSHOTS FROM THE ANCIENT INDO-PACIFIC: REMARKABLE EOCENE FISH FAUNAS AND THEIR IMPLICATIONS FOR THE ORIGIN OF A MODERN MARINE BIODIVERSITY HOTSPOT

世界上一些地区的物种种类比其他地区更多。这些所谓的生物多样性热点是如何随着时间的推移而产生和变化的，这是一个重要的问题，特别是在这些地区受到人类活动的压力的情况下。主要的海洋热点位于印度-西太平洋地区，是地球上鱼类多样性最多的地方。然而，该地区稀少的鱼类化石记录一直是理解这种极其多样化的现代动物起源的障碍。该项目将专注于三个截然不同的巴基斯坦海洋鱼类化石组合，它们开始填补这一空白。这些化石有4800万到4300万年的历史，可以追溯到印度-巴基斯坦时代，当时印度-巴基斯坦是后来成为印度洋的一个大岛。它们提供了旧大陆热带鱼类生活的“快照”，并为了解现代生物多样性热点是如何形成的提供了重要线索。这项研究将为两所公立大学的本科生、硕士和博士生提供培训。研究结果将发表在科学文章中，并在专业会议上公布。该项目的成果将通过可见的准备实验室、在博物馆和其他公共场所举行的活动以及以化石标本、可触摸的铸件和化石鱼类的生命重建为特色的互动展示与公众分享。研究的化石来自巴基斯坦的两个海洋始新世地层，代表三个不同的环境。标本将使用化学方法、机械技术、微型CT扫描或放射照相技术进行准备，具体取决于其保存方式。分类鉴定将通过与现代和化石标本的骨骼标本进行比较来进行。我们将量化巴基斯坦始新世组合与现代和古代海洋鱼类动物群的相似性，以检验在其他分类群基础上提出的海洋生物多样性热点转移的假设。将对选定数量的标本进行详细的解剖学和系统发育分析，其中包括形态、分子和地层数据。由此产生的系统发育将被用来检验一些古近纪早期硬骨鱼中明显的营养和生态创新的时间假说。这一裁决反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Some regions of the world are home to a greater variety of species than others. How these so-called biodiversity hotspots arise and change over time is an important question, especially as these areas are under pressure from human activities. The major marine hotspot lies in the Indo-West Pacific region, and is home to the greatest diversity of fishes anywhere on the planet. The sparse fossil record of fishes in the region, however, has been an obstacle to understanding the origin of this remarkably diverse modern fauna. This project will focus on three distinct assemblages of marine fish fossils from Pakistan that begin to fill this gap. Between 48 and 43 million years old, these fossils date to a time when Indo-Pakistan was a large island in what would become the Indian Ocean. They provide ‘snapshots’ of fish life in the Old World Tropics and provide important clues into how the modern biodiversity hotspot came to be. This study will provide training for undergraduate, Master’s, and PhD students at two public universities. Results will be published in scientific articles and presented at professional meetings. Outcomes from the project will be shared with the public through a combination of visible preparation labs, events held at museums and other public venues, and an interactive display featuring fossil specimens, touchable casts, and life reconstructions of fossil fishes.The fossils examined are from two marine Eocene formations in Pakistan, representing three distinct environments. Specimens will be prepared using chemical approaches, mechanical techniques, micro-CT scanning, or radiography, depending on their mode of preservation. Taxonomic identifications will be made through comparison with skeletal preparations of modern and fossil specimens. We will quantify the similarity of the Eocene assemblages from Pakistan to modern and ancient marine fish faunas to test hypotheses of a shifting marine biodiversity hotspot proposed on the basis of other taxonomic groups. A select number of specimens will be subject to detailed anatomical and phylogenetic analysis incorporating morphological, molecular, and stratigraphic data. Resulting phylogenies will be used to test hypotheses about the timing of trophic and ecological innovation apparent among some early Paleogene teleostean fishes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.