The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb

@article{Shubin2006ThePF,
  title={The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb},
  author={Neil H. Shubin and Edward B. Daeschler and Farish A. Jenkins},
  journal={Nature},
  year={2006},
  volume={440},
  pages={764-771}
}
Wrists, ankles and digits distinguish tetrapod limbs from fins, but direct evidence on the origin of these features has been unavailable. Here we describe the pectoral appendage of a member of the sister group of tetrapods, Tiktaalik roseae, which is morphologically and functionally transitional between a fin and a limb. The expanded array of distal endochondral bones and synovial joints in the fin of Tiktaalik is similar to the distal limb pattern of basal tetrapods. The fin of Tiktaalik was… 
View on Nature
bio.research.ucsc.edu
288 Citations
Highly Influential Citations
25
Background Citations
121
Methods Citations
6
Results Citations
7

288 Citations

The pectoral fin of Panderichthys and the origin of digits
TLDR
A CT scan study of an undisturbed pectoral fin of Panderichthys is presented demonstrating that the plate-like ‘ulnare’ of previous reconstructions is an artefact and that distal radials are in fact present and makes a strong case for fingers not being a novelty of tetrapods but derived from pre-existing distal Radials present in all sarcopterygian fish.
Fish fingers: digit homologues in sarcopterygian fish fins.
TLDR
Evidence suggests that Neoceratodus fin radials and tetrapod digits may be patterned by shared mechanisms distinct from those patterning the proximal fin/limb elements, and in that sense are homologous.
Pelvic girdle and fin of Tiktaalik roseae
TLDR
The mosaic of primitive and derived features in Tiktaalik reveals that the enhancement of the pelvic appendage of tetrapods and, indeed, a trend toward hind limb-based propulsion have antecedents in the fins of their closest relatives.
The pectoral fin muscles of the coelacanth Latimeria chalumnae: Functional and evolutionary implications for the fin‐to‐limb transition and subsequent evolution of tetrapods
TLDR
The functional and evolutionary implications for the fin‐to‐limb transition and subsequent evolution of tetrapods are discussed.
Characteristic tetrapod musculoskeletal limb phenotype emerged more than 400 MYA in basal lobe-finned fishes
TLDR
These findings suggest that the characteristic tetrapod musculoskeletal limb phenotype was already present in the Silurian last common ancestor of extant sarcopterygians, with exception to the autopod (hand/foot) structures, which have no clear correspondence with fish structures.
Reconstructing pectoral appendicular muscle anatomy in fossil fish and tetrapods over the fins‐to‐limbs transition
TLDR
A stepwise sequence of specific appendicular muscle acquisitions, splits, and fusions that led from the ancestral sarcopterygian pectoral fin to the ancestral tetrapod forelimb is postulated, which largely agrees with previous hypotheses based on palaeontological and comparative work, but is much more comprehensive in terms of both muscles and taxa.
Development and Evolution of the Muscles of the Pelvic Fin
TLDR
It is proposed that the adoption of the fully derived mode of hindlimb muscle formation from this bimodal character state is an evolutionary innovation that was critical to the success of the tetrapod transition.
A Devonian tetrapod-like fish and the evolution of the tetrapod body plan
TLDR
The discovery of a well-preserved species of fossil sarcopterygian fish from the Late Devonian of Arctic Canada that represents an intermediate between fish with fins and tetrapods with limbs, and provides unique insights into how and in what order important tetrapod characters arose is reported.
Development of the Pectoral Lobed Fin in the Australian Lungfish Neoceratodus forsteri
TLDR
This study suggests that the acquisition of embryonic mesenchyme at the junction between the axial body wall and the appendicular bud opened the door to the formation of the brachial plexus and the specialization of individual muscles in the lineage that gave rise to tetrapods.
Characteristic tetrapod musculoskeletal limb phenotype
TLDR
New musculoskeletal data from dissections, MRI scans, 3D reconstructions, and histological sections of coelacanths and dipnoans are obtained and will be crucial in paving the way for the use of this method in muscle reconstructions of key tetrapod and non-tetrapod sarcopterygian extinct taxa.
...
...

References

SHOWING 1-10 OF 47 REFERENCES
The tetrapod limb: a hypothesis on its origin.
TLDR
The paleontological evidence for the fin-limb transition is reviewed and it is concluded that the innovation associated with evolution of the tetrapod limb is the zeugopodial-mesopodials transition.
A Devonian tetrapod-like fish and the evolution of the tetrapod body plan
TLDR
The discovery of a well-preserved species of fossil sarcopterygian fish from the Late Devonian of Arctic Canada that represents an intermediate between fish with fins and tetrapods with limbs, and provides unique insights into how and in what order important tetrapod characters arose is reported.
IX.—The Postcranial Skeleton of Ensthenopteron foordi Whiteaves *
TLDR
A functional analysis of the skeleton of Ensthenopteron is attempted, suggesting that it resembled the pike in its mode of life and that it may have been capable of short journeys “walking” overland.
The shoulder girdle of Panderichthys rhombolepis (Gross) (Crossopterygii); Upper Devonian; Latvia
Expression of Hoxa‐11 and Hoxa‐13 in the pectoral fin of a basal ray‐finned fish, Polyodon spathula: implications for the origin of tetrapod limbs
TLDR
The early expression pattern in tetrapods is similar to that seen in late fin development and that the local exclusion by HoxA‐13 of Hoxa‐11 from the distal limb bud is a derived feature of limb developmental regulation.
The axial skeleton of the Devonian tetrapod Ichthyostega
TLDR
A new reconstruction of Ichthyostega is shown based on extensive re-examination of original material and augmented by recently collected specimens and reveals hitherto unrecognized regionalization in the vertebral column.
23 – Perspectives on the Evolutionary Origin of Tetrapod Limbs
The Devonian tetrapod Acanthostega gunnari Jarvik: postcranial anatomy, basal tetrapod interrelationships and patterns of skeletal evolution
TLDR
Comparison between axial skeletons of primitive tetrapods suggests that plesiomorphic fish-like morphologies were re-patterned in a cranio-caudal direction with the emergence of tetrapod vertebral regionalisation.
A NEW SPECIMEN OF SAURIPTERUS TAYLORI (SARCOPTERYGII, OSTEICHTHYES) FROM THE FAMENNIAN CATSKILL FORMATION OF NORTH AMERICA
TLDR
The pectoral fins of Sauripterus were optimized for adduction and flexion against the water column or a solid substrate, suggesting a sister-group relationship between rhizodontids and tetrapods.
Fish with fingers?
TLDR
This discovery reveals that major tetrapod novelties are also seen in the paddles of some closely related fish and therefore need not have arisen to meet the demands of a terrestrial existence.
...
...