Friday, November 03, 2023

Fish, reconsidered: A major update of the ‘Tree of Life’ draws surprising connections

Amazing stuff!

"... drew many surprising connections while completely revising the Tree of Life branches concerning ray-finned fishes, which represent more than 35,000 species — tunas, clown fish, catfish, piranhas, etc. – accounting for nearly all vertebrate fish species and about half of living vertebrate species. ...
Prior to the new revisions, ray-finned fishes were sorted into taxonomic groups largely based on morphology — their physical forms and structures — and other observable traits, which doesn’t capture all relationships among lineages ... Molecular genetic analysis ... has clarified relationships among lineages but, until now, those discoveries have never been synthesized and incorporated into an updated Tree of Life.
“Our knowledge of the fish Tree of Life is dramatically different than it was 20 years ago,” ... “Genetics has upended our understanding of how major fish lineages relate to each other. ...
In all, the researchers defined 97 inclusive groups based on common ancestry, accounting for 830 lineages. Only one of the 97 groups is new. They focused on consolidation, extracting more than 20 group names that they deemed redundant. ..."

From the abstract:
"Classification of the tremendous diversity of ray-finned fishes (Actinopterygii) began with the designation of taxonomic groups based on morphological similarity. Starting in the late 1960s morphological phylogenetics became the basis for the classification of Actinopterygii but failed to resolve many relationships, particularly among lineages
within the hyperdiverse Percomorpha. The introduction of molecular phylogenetics led to a dramatic reconfiguration of actinopterygian phylogeny. Refined phylogenetic resolution afforded by molecular studies revealed an uneven diversity among actinopterygian lineages, resulting in a proliferation of redundant group names in Linnean ranked classifications. Here we provide an unranked phylogenetic classification for actinopterygian fishes based on a summary phylogeny of 830 lineages of ray-finned fishes that includes all currently recognized actinopterygian taxonomic families and 287 fossil taxa. We provide phylogenetic definitions for 90 clade names and review seven previously defined names. For each of the 97 clade names we review the etymology of the clade name, clade species diversity and constituent lineages, clade diagnostic morphological apomorphies, a review of synonyms, and discuss the clade's
nomenclatural and systematic history. The new classification is free of redundant group names and includes only one new name among the 97 clade names we review and describe, yielding a comprehensive classification that is based explicitly on the phylogeny of ray-finned fishes that has emerged in the 21st century and rests on the foundation of the previous 200 years of actinopterygian systematic research."

Fish, reconsidered: An updated ‘Tree of Life’ draws surprising connections | YaleNews In a major new work, ... ichthyologist ... revises branches of the Tree of Life concerning most fish species based on the latest scientific knowledge.




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