New data of phosphatized globular fossils from Weng'an biota in the Ediacaran Doushantuo Formation and the problem concerning their affinity

The affinity of phosphatized globular fossils,one of the important types in the Ediacaran Weng'an biota, was first interpreted as that of green algae.Later,some researchers interpreted these fossils as animal resting eggs and embryos based on the fact that these globular fossils show similar features to early cleavage stages of metazoan embryos from 2-cells to 32-cells and regular arrangement of the cleaving cells,and that they have relatively fixed sizes at various early cleavage stages.The interpretation of metazoan embryos has aroused much interest among palaeontologists,who have paid great attention to Weng'an biota.Recently,some researchers interpreted these globular fossils as giant sulphur bacteria.Some new data of phosphatized globular fossils from Weng'an biota are reported in this paper,including globular fossils with budding structure and transitional forms between Parapandorina and Megaclonophycus.These new data suggest that some characteristics of globular fossils cannot be interpreted by metazoan resting eggs and embryos,though the interpretation of globular fossils from Ediacaran Weng'an biota as embryos is the best hypothesis at present.