part of tissue development lateral line development GO:0048882 The process whose specific outcome is the progression of the lateral line over time, from its formation to the mature structure. The lateral line consists of small sensory patches (neuromasts) located superficially on the skin or just under the skin in fluid-filled canals on the head and body of all fishes and most amphibians. The lateral line develops from cranial ectodermal placodes situated behind the ear and between the eye and ear. LL development biological_process lateral line system development