Honeybee morphogenesis: embryonic cell movements that shape the larval body

Crucial steps in honeybee morphogenesis are characterized by the migration of free epithelial edges while well-defined epithelial cell populations expand or translocate. For each step - dorsal strip invasion, gastrulation, formation of serosa, amnion and midgut - scanning electron microscopy reveals a highly specific syndrome of cell shapes and cell movements at the advancing epithelial edge. Epithelial translocation appears to result from various combinations of ameboid movement, cell flattening, cell rearrangement (intercalation) and cell contraction along the free epithelial edge. The direction of epithelial movements could result essentially from the initial shape and orientation of the edge combined with the cells’ tendency to close vacant spaces by extension and migration. These findings are discussed in relation to morphogenetic movements in other insects and to postembryonic wound healing in insects and amphibians.