Shook, D. R., Kasprowicz, E. M., Davidson, L. A., & Keller, R. (2018). Large, long range tensile forces drive convergence during Xenopus blastopore closure and body axis elongation. Elife, 7, e26944.
See the “Tractor Pull”! Link. Also see perspective, “May the force be with you.” by Shinuo Weng and John Wallingford (link).