During embryonic development, the question of how a fertilized egg achieves a complex multicellular spatio-temporal structure through cell division and differentiation is of great interest to scientists. Sulston et al. found that the embryogenesis of the Caenorhabditis elegans has a very stereotypic developmental pattern, that is, its cell lineage is highly invariant among individual embryos. Not only that, but its cell behavior is also quite conserved. As for how the C. elegans achieves this high-precision developmental pattern, biochemical information such as relevant genes and signaling pathways are known, but little is known about the role of physical factors such as mechanical forces in it. In order to investigate the role of bio-mechanics in development and to further understand the necessity and importance of this precise development pattern for C. elegans, we modeled and analyzed the development process of nematode at the 4-24 cell stage. This work uses a simple mechanical model to simulate the forces between cells and the cell movements due to cell divisions. Simulation results indicate that an appropriate cell division sequence and proper division synchronous are essential for the formation of specific cell arrangement to maintain important cell contact relationships and to ensure that developmental processes proceed normally. In conclusion, combined with statistical analysis of experimental data and numerical simulations of theoretical models, this work provides some insights from a physical perspective for understanding the necessity and importance of maintaining this stereotypical division pattern in embryonic development.
