Morphogenetic arms race: how might mechanics influences evolution

Morphogenesis is the process in which cells, tissues, organs and embryos acquire orderedness, patterns, shapes and higher order organizations. Studies in the last decades began to reveal that morphogenetic processes depend not only on deterministic genetic programs, but also mechanical/physical mechanisms that show hallmarks of stochasticity and self-organization. The involvement of physical mechanisms raises intriguing questions as to how they might influence the evolutionary dynamics of morphogenesis, in conjunction with the well-established evolutionary pathways of descent with genetic modifications. Using early embryonic morphogenesis in the Drosophila as a model system, recent work in my lab shows that: 1) the build-up of compressive stresses during axial elongation and tissue expansion is averted by divergent strategies that act as ‘mechanical sink’ to pre-empt tissue ‘tectonic’ collision; 2) tensile stresses generated during invagination and convergent extension require a cell-intrinsic compliance program to prevent tissue rupture; and 3) efficient yolk compaction via colloidal forces safeguards cell formation and tissue invagination to prevent mechanical instabilities that could arise due to physical impediment of the yolk compartment. These data suggests that physical factors and mechanics might be more than a contributor of morphogenesis, but a facilitator of evolutionary transition and innovation