Ascidian Larvae and the Events of Metamorphosis
Abstract
SYNOPSIS. Ascidian larvae settle and metamorphose after only a brief free—swimming period; they are all lecilhotrophic. Extrinsic factors (chemical and physical) may trigger metamorphosis but none are known to be essential. The major larval structures may be classified as transitory larval organs (TLO), prospective juvenile organs (PJO) or larvaljuvenile organs (LJO). TLO are phagocytized or otherwise destroyed at metamorphosis; the PJO and LJO become the functional parts of the juvenile or oozooid. Metamorphosis involves some rapid and some slow morphogenetic movements. Variations in larval morphology are reflected in metamorphosis. Some of the events of metamorphosis are fairly well known in terms of the role of specific cells but we know little about how the various events are initiated and coordinated. The nervous system is more complex than had been previously assumed. The nervous system, neuroid conduction and diffusion of one or more humoral factors are probably all involved in controlling metamorphosis.
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This environmental-cue-triggered metamorphosis pattern is seen across corals, annelids, molluscs, ascidians and others.
“This pattern is seen across corals, annelids, molluscs, ascidians and others [73-77].”
From An option space for early neural evolution (2015) · cites this paper as [76]
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An option space for early neural evolution
Jékely, G., Keijzer, F., & Godfrey-Smith, P. (2015) · Philosophical Transactions of the Royal Society B: Biological Sciences · doi:10.1098/rstb.2015.0181 · Cited by 171 · see citing works
- Authors
- CLONEY, R. A.
- Affiliations
- University of Washington (US)
- Corresponding author
- CLONEY, RICHARD A.
- Venue
- American Zoologist
- Publisher
- Oxford University Press (OUP)
- Published
- 1982-11
- Volume
- 22
- Issue
- 4
- Pages
- 817-826
- ISSN
- 0003-1569 (ISSN-L)
- OpenAlex
- W1967582304
- Cited by
- 177
- References
- 19
- Citations by year
- 2026: 3 · 2025: 15 · 2024: 6 · 2023: 6 · 2022: 5 · 2021: 5 · 2020: 12 · 2019: 6 · 2018: 10 · 2017: 4 · 2016: 2 · 2015: 6 · 2014: 7 · 2013: 4 · 2012: 5
- FWCI
- 0.34
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- American Zoologist (publishedVersion)
- HighWire Press Open Archive (submittedVersion)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Developmental Biology and Gene Regulation
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Marine Invertebrate Physiology and Ecology
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Biotechnology › Marine Sponges and Natural Products
- Keywords
- ascidian larvae, metamorphosis, larval settlement, lecithotrophy, morphogenetic movements, larval morphology, larval nervous system, humoral factors
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