青年学者发现已知最早轮藻化石 陆地植物起源有了关键证据

Core Insights - The research led by Professor Liu Lijing from Northwestern University has identified the earliest known charophyte fossils in the Tarim and Ordos basins of China, pushing the geological record of these fossils back by approximately 28 million years to the Late Ordovician period [1][2]. Group 1: Fossil Discovery - The discovered fossil samples are marine charophyte calcareous thallus fossils from the early Late Ordovician carbonate strata [2]. - The team named the fossil "Miracle Tarim Charophyte," with the holotype specimen sourced from the Tarim Basin [2]. Group 2: Evolutionary Significance - The fossils exhibit features such as branched structures and differentiated nodes, closely resembling modern charophytes, indicating a conservative evolution of charophyte thalli [3]. - The research confirms the evolutionary relationship between land plants and charophytes, providing critical evidence for the hypothesis that land plants originated from charophytes during the Ordovician period [3]. Group 3: Research Background - Liu Lijing's journey began in 2010 during her doctoral studies, where she discovered numerous "bead-like" broken fossils that were not typical red or green algae [4]. - Between 2010 and 2013, she meticulously documented over 10,000 carbonate thin sections, resulting in a valuable collection of 100,000 photographs that laid the groundwork for her later discoveries [4]. Group 4: Collaborative Efforts - Liu Lijing's research has benefited from collaboration with experts from various institutions, leading to significant breakthroughs in the interdisciplinary study of algae and land plant evolution [5]. - In 2019, she published important findings on Ordovician calcified cyanobacteria, contributing to the understanding of atmospheric CO2 levels [5].