Waves propagated during vertebrate development: observations and comments.

The status and possible roles of propagated waves occurring during vertebrate embryogenesis are discussed. Some preliminary data for waves observed in time-lapse films of early chick (Gallus domesticus) and Medaka (Oryzias latipes, a teleost) are given. The general similarities between these phenomena and wave propagation during cellular slime mold aggregation are pointed out and it is suggested that the control of development by propagated waves in regulative embryos is not only widespread but also depends on a common cellular mechanism.