The current status, problems, and policy suggestions for reconstructing the plant tree of life

Abstract

In 1859, Charles Darwin put forward the concept of the tree of life (TOL), a metaphor for charting relationships between organisms in space and time in his The Origin of Species. The TOL is a cornerstone in evolutionary theory and makes sense of all biology. Decades of research in plant molecular systematics has led to substantial progress in understanding many aspects of the plant TOL. Here, we summarized five major aspects of reconstructing the plant TOL, which are being studied at the present day and will continue to be goals moving forward. These include: (1) constructing genus-and species-level phylogenies for plant groups; (2) resolving deep-time and/or rapidly divergent phylogenetic relationships using genomic approaches; (3) updating classification systems by combining morphological and molecular data; (4) integrating fossil taxa into phylogenies derived from extant taxa; and (5) building big trees using supermatrix methods. We then outlined the current state of plant molecular systematics and highlight existing problems in the field, specifically in regard to China. Finally, we propose the corresponding guidelines and policy suggestions for the continued study of China’s reconstruction of the plant TOL.