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Cited by 355Marine Invertebrate Physiology and EcologyProtist diversity and phylogenyInvertebrate Taxonomy and Ecology

Phylogeny of Medusozoa and the evolution of cnidarian life cycles

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Collins, A. G.·2002·Journal of Evolutionary Biology
DOI 10.1046/j.1420-9101.2002.00403.x
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Abstract

Abstract To investigate the evolution of cnidarian life cycles, data from the small subunit of the ribosome are used to derive a phylogenetic hypothesis for Medusozoa. These data indicate that Cnidaria is monophyletic and composed of Anthozoa and Medusozoa. While Cubozoa and Hydrozoa are well supported clades, Scyphozoa appears to be paraphyletic. Stauromedusae is possibly the sister group of either Cubozoa or all other medusozoans. The phylogenetic results suggest that: the polyp probably preceded the medusa in the evolution of Cnidaria; within Hydrozoa, medusa development involving the entocodon is ancestral; within Trachylina, the polyp was lost and subsequently regained in the parasitic narcomedusans; within Siphonophorae, the float originated prior to swimming bells; stauromedusans are not likely to be descended from ancestors that produced medusae by strobilation; and cubozoan polyps are simplified from those of their ancestors, which possessed polyps with gastric septa and four mesogleal muscle bands and peristomial pits.

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  • The absence of precambrian planktonic metazoans is consistent with an Early Cambrian estimate for the origin of the last common ancestor of living cnidarians, a population whose life cycle lacked a medusa stage and was entirely benthic.

    “The absence of precambrian planktonic metazoans is consistent with our Early Cambrian estimate for the origin of the last common ancestor of living cnidarians, a population of animals whose life cycle lacked a medusa stage and thus was entirely benthic (49).”

    From Estimating metazoan divergence times with a molecular clock (2004) · cites this paper as [49]

    The Cnidaria section says the evidence slightly favors a medusa arising in Medusozoa rather than in the common ancestor of cnidarians. It does not establish that the ancestor’s entire life cycle was benthic; the same section describes a motile planula stage in cnidarian life cycles. The Early Cambrian estimate is explicitly the citing authors’ own, not a finding attributed to this source. (LLM, conf=0.86)

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  • Morphological and 18S ribosomal RNA data place Anthozoa as the most ancestral class within the phylum.

    “Based on morphological and 18S ribosomal RNA data, the Anthozoa appear to be the most ancestral class within the phylum (Bridge et al., 1995;Collins, 2002).”

    From Evolutionary aspects of developmentally regulated helix-loop-helix transcription factors in striated muscle of jellyfish (2003) · cites this paper as Collins, 2002

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3 of the 62 references couldn’t be matched to a known paper.

Research works printed but not linked: 12

  1. Boero, F., Bouillon, J., Piraino, S. & Schmid, V. 1997. Diversity of hydroidomedusan life cycles: ecological implications and evolutionary patterns. Proc. 6th Int. Conf. Coelent. 53-62.
  2. Chapman, D.M. 1966. Evolution of the scyphistoma. In: The Cnidaria and Their Evolution (W. J. Rees, ed.), pp. 51-75. Academic Press, London.
  3. Goy, J. 1979. Meduses. In: Resultats Scientifiques des Campaignes de la Calyps, pp. 263-296.
  4. Meglitsch, P.A. & Schram, F.R. 1991. Invertebrate Zoology, 3rd edn. Oxford University Press, New York.
  5. Mills, C.E. 1987. In situ and shipboard studies of living hydromedusae and hydroids: preliminary observations of life-cycle adaptations to the open ocean. In: Modern Trends on the Systematics, Ecology, and Evolution of Hydroids and Hydromedusae (J. Bouillon, F. Boero, F. Cicogna & P. F. S. Cornelius, eds), pp. 197-207. Clarendon Press, Oxford.
  6. Moore, R.C. & Harrington, H.J. 1956. Scyphozoa. In: Treatise on Invertebrate Paleontology: Part F: Coelenterata (R. C. Moore, ed.), pp. F27-F38. Geological Society of America and University of Kansas, New York and Lawrence.
  7. Otto, J.J. 1978. The settlement of Haliclystus planulae. In: Settlement and Metamorphosis of Marine Invertebrate Larvae (F.-S. Chia & M. E. Rice, eds), pp. 13-20. Elsevier-North Holland, New York.
  8. Petersen, K.W. 1979. Development of coloniality in Hydrozoa. In: Biology and Systematics of Colonial Organisms (G. Larwood & B. R. Rosen, eds), pp. 105-139. Academic Press, New York.
  9. Robson, E.A. 1966. Swimming in Actiniaria. In: The Cnidaria and Their Evolution (W. J. Rees, ed.), pp. 333-372. Academic Press, New York.
  10. Schram, F.R. 1991. Cladistic analysis of metazoan phyla and the placement of fossil problematica. In: The Early Evolution of Metazoa and the Significance of Problematic Taxa (A. M. Simonetta & S. Conway Morris, eds), pp. 35-46. Cambridge University Press, Cambridge.
  11. Thiel, H. 1966. The evolution of the Scyphozoa, a review. In: Cnidaria and Their Evolution (W. J. Rees, ed.), pp. 77-117. Academic Press, London.
  12. Van Iten, H. 1991. Evolutionary affinities of conulariids. In: The Early Evolution of Metazoa and the Significance of Problematic Taxa (A. M. Simonetta & S. Conway Morris, eds), pp. 145-156. Cambridge University Press, Cambridge.

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Authors
Collins, A. G.
Affiliations
University of California, Berkeley (US)
Corresponding author
Collins, A. G.
ORCID
Collins, A. G.
Venue
Journal of Evolutionary Biology
Publisher
Oxford University Press (OUP)
Published
2002-05-01
Volume
15
Issue
3
Pages
418-432
ISSN
  • 1010-061X (ISSN-L)
  • 1420-9101
DOI
10.1046/j.1420-9101.2002.00403.x
OpenAlex
W2098787235
Cited by
355
References
62
Citations by year
2026: 11 · 2025: 8 · 2024: 9 · 2023: 12 · 2022: 16 · 2021: 10 · 2020: 6 · 2019: 13 · 2018: 15 · 2017: 19 · 2016: 21 · 2015: 27 · 2014: 15 · 2013: 9 · 2012: 7
FWCI
17.71
Type
journal article
Language
en
Open access
Licence
Locations
Journal of Evolutionary Biology (publishedVersion)
Funders
National Science Foundation (9814845)
Topics
  • Physical Sciences › Earth and Planetary Sciences › Paleontology › Marine Invertebrate Physiology and Ecology
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Protist diversity and phylogeny
  • Life Sciences › Agricultural and Biological Sciences › Ecology, Evolution, Behavior and Systematics › Invertebrate Taxonomy and Ecology
Keywords
Medusozoa, Anthozoa, Cubozoa, Hydrozoa, Scyphozoa, Siphonophorae, strobilation, monophyly

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