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The Early Origin of the Antarctic Marine Fauna and Its Evolutionary Implications.

Crame JA, Beu AG, Ineson JR, Francis JE, Whittle RJ, Bowman VC - PLoS ONE (2014)

Bottom Line: The extensive Late Cretaceous - Early Paleogene sedimentary succession of Seymour Island, N.E.It is also possible that the marked Early Paleogene expansion of neogastropods in Antarctica is in part due to a global increase in rates of origination following the K/Pg mass extinction event.Evolutionary source - sink dynamics may have been significantly different between the Paleogene greenhouse and Neogene icehouse worlds.

View Article: PubMed Central - PubMed

Affiliation: British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom.

ABSTRACT
The extensive Late Cretaceous - Early Paleogene sedimentary succession of Seymour Island, N.E. Antarctic Peninsula offers an unparalleled opportunity to examine the evolutionary origins of a modern polar marine fauna. Some 38 modern Southern Ocean molluscan genera (26 gastropods and 12 bivalves), representing approximately 18% of the total modern benthic molluscan fauna, can now be traced back through at least part of this sequence. As noted elsewhere in the world, the balance of the molluscan fauna changes sharply across the Cretaceous - Paleogene (K/Pg) boundary, with gastropods subsequently becoming more diverse than bivalves. A major reason for this is a significant radiation of the Neogastropoda, which today forms one of the most diverse clades in the sea. Buccinoidea is the dominant neogastropod superfamily in both the Paleocene Sobral Formation (SF) (56% of neogastropod genera) and Early - Middle Eocene La Meseta Formation (LMF) (47%), with the Conoidea (25%) being prominent for the first time in the latter. This radiation of Neogastropoda is linked to a significant pulse of global warming that reached at least 65°S, and terminates abruptly in the upper LMF in an extinction event that most likely heralds the onset of global cooling. It is also possible that the marked Early Paleogene expansion of neogastropods in Antarctica is in part due to a global increase in rates of origination following the K/Pg mass extinction event. The radiation of this and other clades at ∼65°S indicates that Antarctica was not necessarily an evolutionary refugium, or sink, in the Early - Middle Eocene. Evolutionary source - sink dynamics may have been significantly different between the Paleogene greenhouse and Neogene icehouse worlds.

No MeSH data available.


The fossil record of 38 modern Southern Ocean molluscan genera.Solid lines and dots depict actual fossil occurrences and ranges of 38 molluscan genera (1–26β€Š=β€Š gastropods, 27–38β€Š=β€Š bivalves). Full details as to how the occurrences and ranges were established within the stratigraphic framework are contained within the text and S2 Appendix. Klb 9 represents the topmost Maastrichtian stratigraphic unit of the LBF, KPBβ€Š=β€Š Cretaceous/Paleogene boundary, and (10) is Kplb 10, the recovery interval and topmost informal stratigraphic unit of the LBF. T1–7β€Š=β€Š Telms 1–7 of the LMF; ages (in Ma) are approximate and taken from Montes et al. [117] for the SF, CVF and topmost LMF (Telms 6–7). Further details on the age of the La Meseta Formation are given in S1 Appendix. Gastropods arranged in taxonomic order according to Bouchet & Rocroi [118]; bivalves according to Bouchet & Rocroi [119] and Taylor et al. [120]. 1.Calliotropis; 2. Collonia; 3. Euspira?; 4. Amauropsis?; 5. Falsilunatia; 6. Sinuber; 7. Perissodonta; 8. Probuccinum?; 9. cf. Germonea; 10. Prosipho; 11. Pareuthria; 12. Chlanidota; 13. Trophon; 14. Fulgurofusus; 15. Volutomitra?; 16. Miomelon?; 17. Tractolira; 18. Aforia?; 19. Spirotropis?; 20. Typhlomangelia; 21. Epitonium; 22. Acirsa; 23. Acteon; 24. Neoacteonina; 25. Tornatellaea; 26. Kaitoa; 27. Leionucula; 28. Yoldia (Aequiyoldia); 29. Limopsis; 30. Limatula; 31. Cyclocardia; 32. Parathyasira; 33. Conchocele; 34. Mysella; 35. Gaimardia; 36. Cyamiomactra; 37. Hiatella; 38. Thracia.
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pone-0114743-g002: The fossil record of 38 modern Southern Ocean molluscan genera.Solid lines and dots depict actual fossil occurrences and ranges of 38 molluscan genera (1–26β€Š=β€Š gastropods, 27–38β€Š=β€Š bivalves). Full details as to how the occurrences and ranges were established within the stratigraphic framework are contained within the text and S2 Appendix. Klb 9 represents the topmost Maastrichtian stratigraphic unit of the LBF, KPBβ€Š=β€Š Cretaceous/Paleogene boundary, and (10) is Kplb 10, the recovery interval and topmost informal stratigraphic unit of the LBF. T1–7β€Š=β€Š Telms 1–7 of the LMF; ages (in Ma) are approximate and taken from Montes et al. [117] for the SF, CVF and topmost LMF (Telms 6–7). Further details on the age of the La Meseta Formation are given in S1 Appendix. Gastropods arranged in taxonomic order according to Bouchet & Rocroi [118]; bivalves according to Bouchet & Rocroi [119] and Taylor et al. [120]. 1.Calliotropis; 2. Collonia; 3. Euspira?; 4. Amauropsis?; 5. Falsilunatia; 6. Sinuber; 7. Perissodonta; 8. Probuccinum?; 9. cf. Germonea; 10. Prosipho; 11. Pareuthria; 12. Chlanidota; 13. Trophon; 14. Fulgurofusus; 15. Volutomitra?; 16. Miomelon?; 17. Tractolira; 18. Aforia?; 19. Spirotropis?; 20. Typhlomangelia; 21. Epitonium; 22. Acirsa; 23. Acteon; 24. Neoacteonina; 25. Tornatellaea; 26. Kaitoa; 27. Leionucula; 28. Yoldia (Aequiyoldia); 29. Limopsis; 30. Limatula; 31. Cyclocardia; 32. Parathyasira; 33. Conchocele; 34. Mysella; 35. Gaimardia; 36. Cyamiomactra; 37. Hiatella; 38. Thracia.

Mentions: The Eocene LMF was investigated using transects at both the northern and south-western ends of the area of outcrop (Fig. 1). In the former of these regions the transect stretches from locality DJ. 78 in informal mapping unit Telm 1, through DJ. 77 (Telms 2 & 3) to DJ. 79 & 80 (Telm 3), and finally DJ. 81 (Telm 4). In the latter, Telm 1 was investigated at D9. 208 & 213, Telm 2 at D9. 212, and Telm 5 at D9. 214 (Fig. 1). In addition, extensive use was made of reference sections S1-2/LM86-1 on the western flank of the LMF, and D-8 on the northern flank in the taxonomic monograph published by Stilwell & Zinsmeister ([18], p. 23 & fig. 39). In this work the stratigraphic occurrences at a large number of localities were projected onto the sections and the results presented as four composite range charts([18], figs 40–43). As Stilwell & Zinsmeister ([18], p. 23) pointed out, it is not a straightforward task to combine sections from different localities into a single reference scheme for the whole LMF. This is because of the marked lenticular nature of the Telms and some significant NNE – SSW variations in thickness across the area of outcrop. In this study a single LMF reference section was established using the stratigraphic scheme presented in Casadio et al. ([19], fig, 2). In some cases it was then possible to plot stratigraphic positions and ranges directly onto it with reasonable accuracy, but in others only relative positions such as β€œmid-point in Telm” or β€œupper one-third of Telm” could be obtained. Further details of the ranges used and specimens examined for each taxon are given in the S2 Appendix, which includes a review of all relevant published sources, and the collections of the PRI. Because the biostratigraphical ranges used in this study were established by a variety of different means, and different research groups, it was not possible to fit confidence intervals to them [20].


The Early Origin of the Antarctic Marine Fauna and Its Evolutionary Implications.

Crame JA, Beu AG, Ineson JR, Francis JE, Whittle RJ, Bowman VC - PLoS ONE (2014)

The fossil record of 38 modern Southern Ocean molluscan genera.Solid lines and dots depict actual fossil occurrences and ranges of 38 molluscan genera (1–26β€Š=β€Š gastropods, 27–38β€Š=β€Š bivalves). Full details as to how the occurrences and ranges were established within the stratigraphic framework are contained within the text and S2 Appendix. Klb 9 represents the topmost Maastrichtian stratigraphic unit of the LBF, KPBβ€Š=β€Š Cretaceous/Paleogene boundary, and (10) is Kplb 10, the recovery interval and topmost informal stratigraphic unit of the LBF. T1–7β€Š=β€Š Telms 1–7 of the LMF; ages (in Ma) are approximate and taken from Montes et al. [117] for the SF, CVF and topmost LMF (Telms 6–7). Further details on the age of the La Meseta Formation are given in S1 Appendix. Gastropods arranged in taxonomic order according to Bouchet & Rocroi [118]; bivalves according to Bouchet & Rocroi [119] and Taylor et al. [120]. 1.Calliotropis; 2. Collonia; 3. Euspira?; 4. Amauropsis?; 5. Falsilunatia; 6. Sinuber; 7. Perissodonta; 8. Probuccinum?; 9. cf. Germonea; 10. Prosipho; 11. Pareuthria; 12. Chlanidota; 13. Trophon; 14. Fulgurofusus; 15. Volutomitra?; 16. Miomelon?; 17. Tractolira; 18. Aforia?; 19. Spirotropis?; 20. Typhlomangelia; 21. Epitonium; 22. Acirsa; 23. Acteon; 24. Neoacteonina; 25. Tornatellaea; 26. Kaitoa; 27. Leionucula; 28. Yoldia (Aequiyoldia); 29. Limopsis; 30. Limatula; 31. Cyclocardia; 32. Parathyasira; 33. Conchocele; 34. Mysella; 35. Gaimardia; 36. Cyamiomactra; 37. Hiatella; 38. Thracia.
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Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4262473&req=5

pone-0114743-g002: The fossil record of 38 modern Southern Ocean molluscan genera.Solid lines and dots depict actual fossil occurrences and ranges of 38 molluscan genera (1–26β€Š=β€Š gastropods, 27–38β€Š=β€Š bivalves). Full details as to how the occurrences and ranges were established within the stratigraphic framework are contained within the text and S2 Appendix. Klb 9 represents the topmost Maastrichtian stratigraphic unit of the LBF, KPBβ€Š=β€Š Cretaceous/Paleogene boundary, and (10) is Kplb 10, the recovery interval and topmost informal stratigraphic unit of the LBF. T1–7β€Š=β€Š Telms 1–7 of the LMF; ages (in Ma) are approximate and taken from Montes et al. [117] for the SF, CVF and topmost LMF (Telms 6–7). Further details on the age of the La Meseta Formation are given in S1 Appendix. Gastropods arranged in taxonomic order according to Bouchet & Rocroi [118]; bivalves according to Bouchet & Rocroi [119] and Taylor et al. [120]. 1.Calliotropis; 2. Collonia; 3. Euspira?; 4. Amauropsis?; 5. Falsilunatia; 6. Sinuber; 7. Perissodonta; 8. Probuccinum?; 9. cf. Germonea; 10. Prosipho; 11. Pareuthria; 12. Chlanidota; 13. Trophon; 14. Fulgurofusus; 15. Volutomitra?; 16. Miomelon?; 17. Tractolira; 18. Aforia?; 19. Spirotropis?; 20. Typhlomangelia; 21. Epitonium; 22. Acirsa; 23. Acteon; 24. Neoacteonina; 25. Tornatellaea; 26. Kaitoa; 27. Leionucula; 28. Yoldia (Aequiyoldia); 29. Limopsis; 30. Limatula; 31. Cyclocardia; 32. Parathyasira; 33. Conchocele; 34. Mysella; 35. Gaimardia; 36. Cyamiomactra; 37. Hiatella; 38. Thracia.
Mentions: The Eocene LMF was investigated using transects at both the northern and south-western ends of the area of outcrop (Fig. 1). In the former of these regions the transect stretches from locality DJ. 78 in informal mapping unit Telm 1, through DJ. 77 (Telms 2 & 3) to DJ. 79 & 80 (Telm 3), and finally DJ. 81 (Telm 4). In the latter, Telm 1 was investigated at D9. 208 & 213, Telm 2 at D9. 212, and Telm 5 at D9. 214 (Fig. 1). In addition, extensive use was made of reference sections S1-2/LM86-1 on the western flank of the LMF, and D-8 on the northern flank in the taxonomic monograph published by Stilwell & Zinsmeister ([18], p. 23 & fig. 39). In this work the stratigraphic occurrences at a large number of localities were projected onto the sections and the results presented as four composite range charts([18], figs 40–43). As Stilwell & Zinsmeister ([18], p. 23) pointed out, it is not a straightforward task to combine sections from different localities into a single reference scheme for the whole LMF. This is because of the marked lenticular nature of the Telms and some significant NNE – SSW variations in thickness across the area of outcrop. In this study a single LMF reference section was established using the stratigraphic scheme presented in Casadio et al. ([19], fig, 2). In some cases it was then possible to plot stratigraphic positions and ranges directly onto it with reasonable accuracy, but in others only relative positions such as β€œmid-point in Telm” or β€œupper one-third of Telm” could be obtained. Further details of the ranges used and specimens examined for each taxon are given in the S2 Appendix, which includes a review of all relevant published sources, and the collections of the PRI. Because the biostratigraphical ranges used in this study were established by a variety of different means, and different research groups, it was not possible to fit confidence intervals to them [20].

Bottom Line: The extensive Late Cretaceous - Early Paleogene sedimentary succession of Seymour Island, N.E.It is also possible that the marked Early Paleogene expansion of neogastropods in Antarctica is in part due to a global increase in rates of origination following the K/Pg mass extinction event.Evolutionary source - sink dynamics may have been significantly different between the Paleogene greenhouse and Neogene icehouse worlds.

View Article: PubMed Central - PubMed

Affiliation: British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom.

ABSTRACT
The extensive Late Cretaceous - Early Paleogene sedimentary succession of Seymour Island, N.E. Antarctic Peninsula offers an unparalleled opportunity to examine the evolutionary origins of a modern polar marine fauna. Some 38 modern Southern Ocean molluscan genera (26 gastropods and 12 bivalves), representing approximately 18% of the total modern benthic molluscan fauna, can now be traced back through at least part of this sequence. As noted elsewhere in the world, the balance of the molluscan fauna changes sharply across the Cretaceous - Paleogene (K/Pg) boundary, with gastropods subsequently becoming more diverse than bivalves. A major reason for this is a significant radiation of the Neogastropoda, which today forms one of the most diverse clades in the sea. Buccinoidea is the dominant neogastropod superfamily in both the Paleocene Sobral Formation (SF) (56% of neogastropod genera) and Early - Middle Eocene La Meseta Formation (LMF) (47%), with the Conoidea (25%) being prominent for the first time in the latter. This radiation of Neogastropoda is linked to a significant pulse of global warming that reached at least 65°S, and terminates abruptly in the upper LMF in an extinction event that most likely heralds the onset of global cooling. It is also possible that the marked Early Paleogene expansion of neogastropods in Antarctica is in part due to a global increase in rates of origination following the K/Pg mass extinction event. The radiation of this and other clades at ∼65°S indicates that Antarctica was not necessarily an evolutionary refugium, or sink, in the Early - Middle Eocene. Evolutionary source - sink dynamics may have been significantly different between the Paleogene greenhouse and Neogene icehouse worlds.

No MeSH data available.