Phylogeny of Medusozoa and the evolution of cnidarian life cycles
@article{Collins2002PhylogenyOM, title={Phylogeny of Medusozoa and the evolution of cnidarian life cycles}, author={Allen Gilbert Collins}, journal={Journal of Evolutionary Biology}, year={2002}, volume={15} }
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…
315 Citations
Cnidarian phylogenetic relationships as revealed by mitogenomics
- BiologyBMC Evolutionary Biology
- 2012
These analyses suggest that the shared morphological characters in these groups are plesiomorphies, originated in the branch leading to Medusozoa, and the hypothesis that Staurozoa is the sister group to all the other medusozoans is rejected.
Medusozoan phylogeny and character evolution clarified by new large and small subunit rDNA data and an assessment of the utility of phylogenetic mixture models.
- BiologySystematic biology
- 2006
A newly compiled data set of nearly complete sequences of the large subunit of the nuclear ribosome (LSU or 28S) sampled from 31 diverse medusozoans greatly clarifies the phylogenetic history of…
Phylogenetic analysis with multiple markers indicates repeated loss of the adult medusa stage in Campanulariidae (Hydrozoa, Cnidaria).
- BiologyMolecular phylogenetics and evolution
- 2006
Molecular phylogenetics of the siphonophora (Cnidaria), with implications for the evolution of functional specialization.
- BiologySystematic biology
- 2005
Maximum likelihood and Bayesian analyses of morphological data suggest that the transition rate for decreased functional specialization is greater than the Transition rate for increased functional specialization for three out of the four investigated categories of polyps and medusae.
Phylogenetic placement of the enigmatic parasite, Polypodium hydriforme, within the Phylum Cnidaria
- BiologyBMC Evolutionary Biology
- 2007
Evidence is provided that Polypodium is indeed a cnidarian and is either the sister taxon to Hydrozoa, or part of the hydrozoan clade, Leptothecata, and previously conflicting hypotheses concerning the phylogenetic placement ofPolypodium can be reconciled.
Cladistic analysis of Medusozoa and cnidarian evolution
- Biology
- 2005
A cladistic analysis of 87 morphological and life history characters of medusozoan cnidarians, rooted with Anthozoa, results in the phylogenetic hypothesis (Anthozoa (Hydrozoa (Scyphozoa) (StaurozoA, Cubozoa))) and a phylogenetic classification of Medusozoa that is consistent with phylogenetic hypotheses based on cladistic results, as well as those derived from 18S analyses.
The phylogenetic position of the comb jellies (Ctenophora) and the importance of taxonomic sampling
- Biology
- 2004
The reconstructed topology is considered to represent the current best hypothesis of the interrelationships of these old lineages and morphological features supporting alternative hypotheses are discussed in the light of this result.
Phylogenetics of Trachylina (Cnidaria: Hydrozoa) with new insights on the evolution of some problematical taxa
- BiologyJournal of the Marine Biological Association of the United Kingdom
- 2008
Molecular data are brought to bear on the question of phylogenetic relationships within Trachylina, suggesting that the polyp stage has been lost independently at least two times within trachyline evolution.
Evolution of box jellyfish (Cnidaria: Cubozoa), a group of highly toxic invertebrates
- BiologyProceedings of the Royal Society B: Biological Sciences
- 2009
The phylogenetic hypothesis suggests that the last common ancestor of Carybdeida probably possessed the mechanism(s) underlying Irukandji syndrome, and deep divergences between Atlantic and Indo-Pacific clades may be explained by ancient vicariant events.
Solution to the phylogenetic enigma of Tetraplatia, a worm-shaped cnidarian
- BiologyBiology Letters
- 2005
Data presented here from the large and small subunits of the nuclear ribosome leave little doubt that Tetraplatia is in fact a hydrozoan genus, and its precise phylogenetic position is within Narcomedusae, as some authors had previously deduced based on structural characters.
References
SHOWING 1-10 OF 86 REFERENCES
The demise of a phylum of protists: phylogeny of Myxozoa and other parasitic cnidaria.
- BiologyThe Journal of parasitology
- 1995
Reassessment of myxozoans as metazoans reveals terminal differentiation, typical metazoan cellular junctions, and collagen production, and it is recommended that the group as a whole be removed from all protistan classifications and placed in a more comprehensive cnidarian system.
Towards understanding the phylogenetic history of Hydrozoa: Hypothesis testing with 18S gene sequence data*
- Biology
- 2000
Parsimony analyses of two datasets that include the new 18S sequences are used to assess the relative strengths and weaknesses of a list of phylogenetic hypotheses that deal with Hydrozoa, and the monophyly of HydrozoA is strongly supported.
Evaluating multiple alternative hypotheses for the origin of Bilateria: an analysis of 18S rRNA molecular evidence.
- BiologyProceedings of the National Academy of Sciences of the United States of America
- 1998
Six alternative hypotheses for the phylogenetic origin of Bilateria are evaluated by using complete 18S rRNA gene sequences for 52 taxa to suggest that there is little support for three of these hypotheses, but one is most strongly supported.
A new perspective on lower metazoan relationships from 18S rDNA sequences.
- BiologyMolecular biology and evolution
- 1999
While sequencing additional lineages to identify slowly evolving taxa, the number of complete or nearly complete 18S rDNA sequences for the major diploblastic lineages was increased and the maximum-likelihood framework was used to choose a model which best explains the data.
Evolution and taxonomy in capitate hydroids and medusae (Cnidaria: Hydrozoa)
- Biology
- 1990
In those families where the reduction of the medusa can be analysed, it is shown that the reduction occurred after all synapomorphies defining the genera had evolved and usually affected individual species within a genus rather than the original species from which the other species in the genus evolved.
Animal phylogeny and the ancestry of bilaterians: inferences from morphology and 18S rDNA gene sequences
- BiologyEvolution & development
- 2001
Because chaetognaths and lophophorates, taxa traditionally allied with deuterostomes, occupy basal positions within their respective protostomian clades, deuterstomy most likely represents a suite of characters plesiomorphic for bilaterians.
Defining phyla: evolutionary pathways to metazoan body plans
- BiologyEvolution & development
- 2001
It is concluded that a benthic radiation of animals could have supplied the ancestral lineages of all but a few phyla, is consistent with molecular evidence, accords well with fossil evidence, and accounts for some of the difficulties in phylogenetic analyses of phyla based on morphological criteria.
Class-level relationships in the phylum Cnidaria: evidence from mitochondrial genome structure.
- BiologyProceedings of the National Academy of Sciences of the United States of America
- 1992
The structure of the mitochondrial genome in representatives of the four extant cnidarian classes and in the phylum Ctenophora is surveyed, finding that all anthozoan species tested possess mtDNA in the form of circular molecules, whereas all scyphozoan, cubozoa, and hydrozoan species tested display mt DNA in the forms of linear molecules.
Life Cycle of Tripedalia cystophora Conant (Cubomedusae)
- BiologyNature
- 1971
The opinion, held by many zoologists, that the Cubomedusae are an aberrant order of the Class Scyphozoa has therefore derived from a knowledge of the medusa generation alone, and the view of some authors that the polyp is the stem form of all recent Cnidaria, have led to efforts to elucidate the life cycle of a member of this order.
Recent Advances in Our Knowledge of the Myxozoa
- BiologyThe Journal of eukaryotic microbiology
- 2001
It is indicated that the Myxozoa are closely related to Cnidaria, and marine taxa at the genus level branch separately from genera that usually infect freshwater fishes; taxa cluster more by development and tissue location than by spore morphology.