Cellular and Subcellular Structure of Neoproterozoic Animal Embryos

@article{Hagadorn2006CellularAS,
  title={Cellular and Subcellular Structure of Neoproterozoic Animal Embryos},
  author={James W. Hagadorn and Shuhai Xiao and Philip C. J. Donoghue and Stefan Bengtson and Neil J. Gostling and Maria M. Pawlowska and Elizabeth C. Raff and Rudolf A. Raff and F. Rudolf Turner and Yin Chongyu and Chuanming Zhou and Xunlai Yuan and Matthew B McFeely and Marco Stampanoni and Kenneth H. Nealson},
  journal={Science},
  year={2006},
  volume={314},
  pages={291 - 294}
}
Stereoblastic embryos from the Doushantuo Formation of China exhibit occasional asynchronous cell division, with diminishing blastomere volume as cleavage proceeded. Asynchronous cell division is common in modern embryos, implying that sophisticated mechanisms for differential cell division timing and embryonic cell lineage differentiation evolved before 551 million years ago. Subcellular structures akin to organelles, coated yolk granules, or lipid vesicles occur in these embryos. Paired… 

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