A simple visual system without neurons in jellyfish larvae
Nordström, Karin, Wallén, Rita, Seymour, Jamie, and Nilsson, Dan (2003) A simple visual system without neurons in jellyfish larvae. Proceedings of the Royal Society of London Series B, Biological Sciences, 270 (1531). pp. 2349-2354.
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Earlier detailed studies of cnidarian planula larvae have revealed a simple nervous system but no eyes or identifiable light sensing structures. Here, we describe the planula of a box jellyfish, Tripedalia cystophora, and report that these larvae have an extremely simple organization with no nervous system at all. Their only advanced feature is the presence of 10–15 pigment–cup ocelli, evenly spaced across the posterior half of the larval ectoderm. The ocelli are single cell structures containing a cup of screening pigment filled with presumably photosensory microvilli. These rhabdomeric photoreceptors have no neural connections to any other cells, but each has a well–developed motor-cilium, appearing to be the only means by which light can control the behaviour of the larva. The ocelli are thus self–contained sensory–motor entities, making a nervous system superfluous.
|Item Type:||Article (Refereed Research - C1)|
|Keywords:||Chironex fleckeri; Chiropsalmus sp.; pigment-cup ocelli; planula; rhabdomeric photoreceptor; Tripedalia cystophora|
|Date Deposited:||25 Mar 2010 02:11|
|FoR Codes:||06 BIOLOGICAL SCIENCES > 0601 Biochemistry and Cell Biology > 060199 Biochemistry and Cell Biology not elsewhere classified @ 100%|
|SEO Codes:||97 EXPANDING KNOWLEDGE > 970106 Expanding Knowledge in the Biological Sciences @ 100%|
|Citation Count from Web of Science||