A simple visual system without neurons in jellyfish larvae.
2003 (English)In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 270, no 1531, 2349-54 p.Article in journal (Refereed) Published
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.
Place, publisher, year, edition, pages
2003. Vol. 270, no 1531, 2349-54 p.
IdentifiersURN: urn:nbn:se:uu:diva-181511DOI: 10.1098/rspb.2003.2504PubMedID: 14667350OAI: oai:DiVA.org:uu-181511DiVA: diva2:556312