Romer's gap

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Permian

Devonian

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Palæozoic

Axis scale: millions of years ago.

Known fossil ranges.
Ghost lineages.

1: "Anthracosauria" 2: Temnospondyli 3: "Microsauria" 4: Seymouriamorpha 5: Diadectidae 6: Nectridea 7: Aistopoda 8: Amniota 9: Baphetidae 10: Colosteidae 11: Gephyrostegidae 12: Casineria 13: Crassigyrinus 14: Whatcheeriidae 15: Adelogyrinidae 16: Ventastega 17: Ichthyostega 18: Acanthostega 19: Tulerpeton

References: Smithson et al. (2012)^[1]

Romer's gap is an apparent gap in the Paleozoic tetrapod fossil record used in the study of evolutionary biology, which represent periods from which excavators have not yet found relevant fossils. It is named after American paleontologist Alfred Romer, who first recognised it in 1956.^[2]^[3] Recent discoveries in Scotland are beginning to close this gap in palaeontological knowledge.^[4]^[5]

^ Smithson, T.R.; Wood, S.P.; Marshall, J.E.A. & Clack, J.A. (2012). "Earliest Carboniferous tetrapod and arthropod faunas from Scotland populate Romer's Gap". Proceedings of the National Academy of Sciences of the United States of America. 109 (12): 4532–4537. Bibcode:2012PNAS..109.4532S. doi:10.1073/pnas.1117332109. PMC 3311392. PMID 22393016.
^ Coates, Michael I.; Clack, Jennifer A. (1995). "Romer's gap: tetrapod origins and terrestriality". Bulletin du Muséum National d'Histoire Naturelle. 17: 373–388. ISSN 0181-0642.
^ By 1955 (perhaps even earlier), Romer states that few good fossils of tetrapods have been recovered from early Carboniferous deposits. See: Romer, Alfred Sherwood (presented: November 11, 1955 ; published: June 28, 1956) "The early evolution of land vertebrates," Proceedings of the American Philosophical Society, 100 (3) : 151-167; see especially page 166. Available on-line at: JSTOR.
^ Clack, Jennifer A.; Bennett, Carys E.; Carpenter, David K.; Davies, Sarah J.; Fraser, Nicholas C.; Kearsey, Timothy I.; Marshall, John E. A.; Millward, David; Otoo, Benjamin K. A.; Reeves, Emma J.; Ross, Andrew J.; Ruta, Marcello; Smithson, Keturah Z.; Smithson, Timothy R.; Walsh, Stig A. (2016). "Phylogenetic and environmental context of a Tournaisian tetrapod fauna" (PDF). Nature Ecology & Evolution. 1 (1): 0002. Bibcode:2016NatEE...1....2C. doi:10.1038/s41559-016-0002. PMID 28812555. S2CID 22421017.
^ Tarlach, Gemma (December 5, 2016). "Tetrapod Triumph! Solving Mystery Of First Land Vertebrates". dead things. Discover. Archived from the original on August 3, 2019. Retrieved December 22, 2016.

[SWMC12-1] Smithson, T.R.; Wood, S.P.; Marshall, J.E.A. & Clack, J.A. (2012). "Earliest Carboniferous tetrapod and arthropod faunas from Scotland populate Romer's Gap". Proceedings of the National Academy of Sciences of the United States of America. 109 (12): 4532–4537. Bibcode:2012PNAS..109.4532S. doi:10.1073/pnas.1117332109. PMC 3311392. PMID 22393016.

[Coates_and_Clack-2] Coates, Michael I.; Clack, Jennifer A. (1995). "Romer's gap: tetrapod origins and terrestriality". Bulletin du Muséum National d'Histoire Naturelle. 17: 373–388. ISSN 0181-0642.

[3] By 1955 (perhaps even earlier), Romer states that few good fossils of tetrapods have been recovered from early Carboniferous deposits. See: Romer, Alfred Sherwood (presented: November 11, 1955 ; published: June 28, 1956) "The early evolution of land vertebrates," Proceedings of the American Philosophical Society, 100 (3) : 151-167; see especially page 166. Available on-line at: JSTOR.

[Clacketal2016-4] Clack, Jennifer A.; Bennett, Carys E.; Carpenter, David K.; Davies, Sarah J.; Fraser, Nicholas C.; Kearsey, Timothy I.; Marshall, John E. A.; Millward, David; Otoo, Benjamin K. A.; Reeves, Emma J.; Ross, Andrew J.; Ruta, Marcello; Smithson, Keturah Z.; Smithson, Timothy R.; Walsh, Stig A. (2016). "Phylogenetic and environmental context of a Tournaisian tetrapod fauna" (PDF). Nature Ecology & Evolution. 1 (1): 0002. Bibcode:2016NatEE...1....2C. doi:10.1038/s41559-016-0002. PMID 28812555. S2CID 22421017.

[5] Tarlach, Gemma (December 5, 2016). "Tetrapod Triumph! Solving Mystery Of First Land Vertebrates". dead things. Discover. Archived from the original on August 3, 2019. Retrieved December 22, 2016.

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