Sarcopterygian fin ontogeny elucidates the origin of hands with digits.
Title | Sarcopterygian fin ontogeny elucidates the origin of hands with digits. |
Publication Type | Journal Article |
Year of Publication | 2020 |
Authors | Woltering JM, Irisarri I, Ericsson R, Joss JMP, Sordino P, Meyer A |
Journal | Sci Adv |
Volume | 6 |
Issue | 34 |
Pagination | eabc3510 |
Date Published | 2020 Aug |
ISSN | 2375-2548 |
Abstract | How the hand and digits originated from fish fins during the Devonian fin-to-limb transition remains unsolved. Controversy in this conundrum stems from the scarcity of ontogenetic data from extant lobe-finned fishes. We report the patterning of an autopod-like domain by during fin development of the Australian lungfish, the most closely related extant fish relative of tetrapods. Differences from tetrapod limbs include the absence of digit-specific expansion of and and distal limitation of and , which potentially evolved through an enhanced response to signaling in limbs. These developmental patterns indicate that the digit program originated in postaxial fin radials and later expanded anteriorly inside of a preexisting autopod-like domain during the evolution of limbs. Our findings provide a genetic framework for the transition of fins into limbs that supports the significance of classical models proposing a bending of the tetrapod metapterygial axis. |
DOI | 10.1126/sciadv.abc3510 |
Alternate Journal | Sci Adv |
PubMed ID | 32875118 |
PubMed Central ID | PMC7438105 |