On the evening of October 27, Beijing time, the journal Nature published the latest research results of Doctoral Student Zhang Zhiliang and others under the guidance of Professor Zhang Zhifei of the Early Life and Environment Innovation Research Team of Northwest University - "Fossil Evidence Reveals that the Moss Phylum originated in the Early Cambrian Period", announcing that Northwest University researchers found the earliest known fossil of bryozoans (bryophytes) on earth in Zhenba County. The discovery pushed the origins of mosses forward by at least 50 million years.
Earliest restoration of bryozoans.
This research result further supports the hypothesis of the "three-act Cambrian explosion" proposed by the team of academician Shu Degan of Northwest University, improves the construction process of cambrian earth animal trees that lasted 40 million years, and effectively connects the explosive and phased fossil evidence chains of the three major animal sublimitations (basic animals, proto-mouth animals and post-mouth animals).
Details of a fossil scan of a bryozoan (bryophyte).
The Cambrian explosion is the most magnificent event known on Earth for the eruption of life by symmetrical animals on both sides. Between 540 million and 518 million years ago, early ancestor representatives of almost all modern animals, including vertebrates, suddenly exploded in the oceans. However, the moss phylum has been considered a product of ordovician radiation due to the lack of a solid Cambrian fossil record.
The research team of Northwest University discovered millimeter-sized microites in the bio-clastic limestone of the Xi artemisia section of the Xiaoyangba Cross-sectional Light shadow formation in Zhenba County through acid etching experiments. The team, together with Macquarie University in Australia, the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences, the British Natural History Museum, the Swedish Museum of Natural History, etc. to conduct further research, believing that these microfiberites are the earliest bryophyte fossils on Earth, revealing the Cambrian origin of this family, indicating that cambrian moss fossils are the basal stem taxons of bryozoans, representing the most primitive ancestor types of bryophytes.
At the same time, Zhang Zhiliang and other researchers analyzed the fossils by scanning electron microscopy and X-ray tomography, and believed that the multi-level plasticity and complex modular construction of the bryozoan population originated 530 million years ago, elucidating important ecological innovations during the Cambrian explosion.
Bryophytes are tiny, typically clad reefers, and usually live on other shell animals or on the surface of hard-bottomed oceans. The discovery of bryozoan (bryophyte) fossils in the argillaceous limestones of southern Shaanxi indicates that Cambrian bryozoans are similar to later genera and are suitable for living in a clear hard-bottom environment, revealing the reason for the lack of bryozoan fossils in the mud shale fossil pool. Academician Shudegan said: "In the past, many paleontologists only found that the earliest fossil record of bryozoans was in the Ordovician period more than 400 million years ago, and now, the Northwestern University research team has found reliable evidence that they originated more than 500 million years ago, advancing their origin by at least 50 million years." The study of such fossils is of great significance for understanding the evolution of the Earth's habitability and how benthic (grass-roots) animals have transformed and adapted the Earth. (Reporter Lu Yang)
Photos are courtesy of Northwestern University
Source: Shaanxi Daily