The initial radiation of vascular land plants is considered to be the plant on -site of the vascular land plants due to an increase in both diversity and morphological inequality during the Silurian and Devonian periods, which can be seen as a terrestrial counterpart of the cambrian explosion of marine animals. During this period, the novel structures such as traquids, stomata, leaves, roots, and secondary zilem developed. However, the development of life-history strategies in early land plants is poorly understood.
