Temporal trends in academic performance and career duration of principal investigators in ecology and evolutionary biology in Taiwan

Academic job markets have become increasingly challenging worldwide, with rising performance requirements for recruitment as a new faculty member and promotion to full professor in recent years. However, it remains underexplored how research performance and other determinants of academic success, including PhD university origin, prestige, and gender, affect recruitment and promotion over time. Focusing on the field of ecology and evolutionary biology in Taiwan, we analyzed the academic performance (measured as h-index) as well as the duration before recruitment and promotion of 145 principal investigators (PIs) over the past 34 years. We found that the performance of PIs before recruitment and before promotion both increased in recent years, and male PIs had on average higher performance than female PIs before recruitment. Moreover, the career duration before recruitment and before promotion both increased in recent years. PIs with Taiwanese PhD degrees tended to have longer duration before recruitment. PhD university ranking had no effect on performance and duration either before recruitment or before promotion. We also found that academic performance of PIs recruited in recent years decreased post-recruitment. Furthermore, PIs with Taiwanese PhD degrees appeared to exhibit a drop in performance post-promotion compared to those with foreign degrees. Taken together, our study reveals increased academic performance requirements and career duration of PIs in ecology and evolutionary biology in Taiwan over the last three decades, and illustrates the role of PhD degree and gender in determining academic success.