The discovery of a fossil trunk of 374 million years ago enabled researchers from the Chinese Institute of Nanjing Geology and Paleontology, with colleagues from the University of Cardiff and State University of New York to investigate the particular growth mechanisms of these "prehistoric" trees.
The fossils belonging to the Cladoxylopsida class allowed scholars to understand that ancient trees were able to reach large dimensions thanks to a truly unique method, with the construction of a circular internal skeleton, a cable, surrounded by the dense mesh of the beams of the xylemas, interconnected by each other, concentrated under the bark.
Around each of these bundles, the growth rings were deposited, giving rise to a structure resembling that of so many small grouped trees. As the xylene beams grow, the diameter of the trunk grows, while the growing weight leads to the collapse to the base of the woody filaments, giving the tree a "bulb" shape.
Research has been published over the past few days and can be consulted at the Nanjing Institute website (http://english.nigpas.cas.cn/).