Exploring the macroevolutionary processes of biological complexity from different perspectives is of great significance to the in-depth understanding of biological evolution. However, to accurately describe the evolutionary trend of biological complexity is challenging since biological complexity is difficult to define and quantify, and the model of analysis of evolutionary trends in biological systems is largely determined by its definition Based on previous studies of taxonomic diversity and morphological disparity, it is helpful to promote the in-depth study of macroevolutionary mechanism of organisms by exploring the biological complexity and its evolutionary trend and establishing the corresponding application models. Given that this research direction has not received widespread attention, this paper aims to deepen the understanding of the concept of biological complexity by reviewing the current status and development of the research on biological complexity, with the goal of promoting its application and development in paleontology and evolutionary biology.
