1Present address: Institut de Biologie Cellulaire et de Morphologie, Rue du Bugnon 9, CH-1005 Lausanne, Switzerland.
Evolution of posterior lateral line development in fish and amphibians
Article first published online: 21 APR 2004
Evolution & Development
Volume 6, Issue 3, pages 187–193, May 2004
How to Cite
Pichon, F. and Ghysen, A. (2004), Evolution of posterior lateral line development in fish and amphibians. Evolution & Development, 6: 187–193. doi: 10.1111/j.1525-142X.2004.04024.x
- Issue published online: 21 APR 2004
- Article first published online: 21 APR 2004
Summary The lateral line is a sensory system present in fish and amphibians. It is composed of discrete sense organs, the neuromasts, arranged on the head and body in species-specific patterns. The neuromasts are deposited by migrating primordia that originate from pre- and postotic placodes and follow defined pathways on the head and body. Here we examine the formation of the posterior lateral line (PLL), which extends rostrocaudally on the trunk and tail. In amphibians, the PLL neuromasts are deposited as a single wave from the head to the tip of the tail. In the zebrafish, however, the first wave of neuromast deposition forms but a rudimentary PLL, and several additional waves are needed to form the adult pattern. We show that the amphibian mode is also present in the sturgeon and therefore probably represents the primitive mode, whereas the zebrafish mode is highly conserved in several teleost species. A third mode is found in a subgroup of teleosts, the protacanthopterygians, and may represent a synapomorphy of this group. Altogether, the mode of formation of the embryonic PLL appears to have undergone remarkably few changes during the long history of anamniote evolution, even though large differences can be observed in the lateral line morphology of adult fishes.