NOTE: The cladograms posted on these pages were assembled using selected information from several sources (but see Important Notes About Animal Relations below), including:
Recent molecular data are raising questions about many of the classical relationships presented in Zool250.
Important differences include:
For another detailed consideration of phylogenetic relations that includes fossil taxa & references to original literature, see Mikko's Phylogeny Archive Page or the University of California Museum of Paleontology.
Some recent, accessible papers on molecular phylogenies for animal phyla include:
CONCLUSION: Experts disagree about which tree is closest to the 'true' phylogenetic tree of animal life, which means we have much yet to learn about how molecules and morphology evolve, and about which evidence provides more valuable clues. Beware trees that do not emphasize well-defined synapomorphies!
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