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This isn't paleontology per se, but has important implications.
https://www.science.org/doi/10.1126/sciadv.adt1576
Coelacanths illuminate deep-time evolution of cranial musculature in
jawed vertebrates
Abstract
Coelacanths are rare fishes that occupy a key evolutionary position in
the vertebrate tree of life. Despite being exhaustively studied, we
found that a substantial part of the knowledge on their cranial
musculature was mistaken. Eleven previously reported coelacanth rCLmusclesrCY are nonexistent, while three previously unknown muscle subdivisions and connections are found. These findings markedly affect
our understanding of the deep-time cranial evolution of jawed
vertebrates (gnathostomes). Only 13% of the previously identified
myological evolutionary novelties for the major gnathostome lineages
proved to be accurate, but several new ones are proposed. We show that
low, moderate, and high levels of cranial muscle innovation
characterized the emergence of lobe-finned (sarcopterygian),
cartilaginous (chondrichthyan), and ray-finned (actinopterygian) fishes, respectively. The novelties in the latter group resulted in the
evolution of a second active mechanism for the expansion of the oropharyngeal cavity, which was probably crucial for the predominance of suction feeding versus bite feeding in extant actinopterygians.
On 7/29/25 9:30 AM, erik simpson wrote:
This isn't paleontology per se, but has important implications.
https://www.science.org/doi/10.1126/sciadv.adt1576
Coelacanths illuminate deep-time evolution of cranial musculature in
jawed vertebrates
Abstract
Coelacanths are rare fishes that occupy a key evolutionary position in
the vertebrate tree of life. Despite being exhaustively studied, we
found that a substantial part of the knowledge on their cranial
musculature was mistaken. Eleven previously reported coelacanth
rCLmusclesrCY are nonexistent, while three previously unknown muscle
subdivisions and connections are found. These findings markedly affect
our understanding of the deep-time cranial evolution of jawed
vertebrates (gnathostomes). Only 13% of the previously identified
myological evolutionary novelties for the major gnathostome lineages
proved to be accurate, but several new ones are proposed. We show that
low, moderate, and high levels of cranial muscle innovation
characterized the emergence of lobe-finned (sarcopterygian),
cartilaginous (chondrichthyan), and ray-finned (actinopterygian)
fishes, respectively. The novelties in the latter group resulted in
the evolution of a second active mechanism for the expansion of the
oropharyngeal cavity, which was probably crucial for the predominance
of suction feeding versus bite feeding in extant actinopterygians.
While the details of coelacanth muscles may be surprising, is the
conclusion so in any way? Are there important actinopterygian novelties previously unknown to be novelties?
On 7/30/25 8:01 AM, John Harshman wrote:
On 7/29/25 9:30 AM, erik simpson wrote:
This isn't paleontology per se, but has important implications.
https://www.science.org/doi/10.1126/sciadv.adt1576
Coelacanths illuminate deep-time evolution of cranial musculature in
jawed vertebrates
Abstract
Coelacanths are rare fishes that occupy a key evolutionary position
in the vertebrate tree of life. Despite being exhaustively studied,
we found that a substantial part of the knowledge on their cranial
musculature was mistaken. Eleven previously reported coelacanth
rCLmusclesrCY are nonexistent, while three previously unknown muscle
subdivisions and connections are found. These findings markedly
affect our understanding of the deep-time cranial evolution of jawed
vertebrates (gnathostomes). Only 13% of the previously identified
myological evolutionary novelties for the major gnathostome lineages
proved to be accurate, but several new ones are proposed. We show
that low, moderate, and high levels of cranial muscle innovation
characterized the emergence of lobe-finned (sarcopterygian),
cartilaginous (chondrichthyan), and ray-finned (actinopterygian)
fishes, respectively. The novelties in the latter group resulted in
the evolution of a second active mechanism for the expansion of the
oropharyngeal cavity, which was probably crucial for the predominance
of suction feeding versus bite feeding in extant actinopterygians.
While the details of coelacanth muscles may be surprising, is the
conclusion so in any way? Are there important actinopterygian
novelties previously unknown to be novelties?
The article is far beyond my capacity to follow regarding fish anatomy.
The main takaway I see is the actinopterygians developed methods of
eating after the divergence from sarcopterygians.