The sustainability of the academic ecosystem relies on researcher demographics and gender balance, yet assessing these dynamics in a timely manner for policy is challenging. Here, we propose a researcher population pyramid framework for tracking demographic and gender trajectories across countries using publication data. We provide a timely snapshot of historical and present demographics and gender balance across 58 countries, revealing three contrasting patterns among research systems: Emerging systems (e.g., Arab countries) exhibit high researcher inflows with widening gender gaps in cumulative productivity; Mature systems (e.g., the United States) show modest inflows with narrowing gender gaps; and Rigid systems (e.g., Japan) lag in both. Furthermore, by simulating future scenarios, the framework makes potential trajectories visible. If 2023 demographic patterns persist, Arab countries' systems could resemble mature or even rigid ones by 2050. Our framework provides a robust diagnostic tool for policymakers worldwide to foster sustainable talent pipelines and gender equality in academia.

翻译：学术生态系统的可持续性依赖于研究者的人口统计特征和性别平衡，然而及时评估这些动态以支持政策制定仍面临挑战。本文提出一种研究人员人口金字塔框架，利用出版数据追踪各国人口统计与性别轨迹。我们提供了58个国家历史与当前人口统计及性别平衡的及时快照，揭示研究系统间三种对比模式：新兴系统（如阿拉伯国家）呈现高研究者流入与累积生产力性别差距扩大；成熟系统（如美国）显示适度流入与性别差距缩小；僵化系统（如日本）则在两方面均滞后。此外，通过模拟未来情景，该框架使潜在轨迹可视化。若2023年的人口统计模式持续，阿拉伯国家的系统到2050年可能趋近成熟甚至僵化系统。本框架为全球政策制定者提供稳健的诊断工具，以促进学术界可持续人才储备与性别平等。