Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history
Investigation of the evolution of calcareous nannoplankton is hindered by the extremely small size (5-10 μm) of their fossils. We introduce new technology, a scanning electron microscope connected to an image analysis system (SEM-IAS), which allows this field to be explored as never before. This sys...
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Language: | English |
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Cambridge University Press (CUP)
1996
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Online Access: | http://dx.doi.org/10.1017/s009483730001633x https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S009483730001633X |
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crcambridgeupr:10.1017/s009483730001633x 2024-03-03T08:38:19+00:00 Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history Bralower, Timothy J. Parrow, Matthew 1996 http://dx.doi.org/10.1017/s009483730001633x https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S009483730001633X en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Paleobiology volume 22, issue 3, page 352-385 ISSN 0094-8373 1938-5331 Paleontology General Agricultural and Biological Sciences Ecology Ecology, Evolution, Behavior and Systematics journal-article 1996 crcambridgeupr https://doi.org/10.1017/s009483730001633x 2024-02-08T08:44:39Z Investigation of the evolution of calcareous nannoplankton is hindered by the extremely small size (5-10 μm) of their fossils. We introduce new technology, a scanning electron microscope connected to an image analysis system (SEM-IAS), which allows this field to be explored as never before. This system enables a host of morphocharacters to be measured and included in studies of phylogeny and evolutionary dynamics. We have applied the SEM-IAS to study the evolution of Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania. A variety of detailed measurements have been made on over 4000 coccoliths from Deep Sea Drilling Project Site 384 in the temperate North Atlantic and Ocean Drilling Program Site 690 in the Weddell Sea off Antarctica. Our results indicate no simple relationships between morphocharacters, the shapes of all three genera are both complex and highly variable. Although most morphocharacters possess little phylogenetic significance, the areas of different shield cycles show gradual divergence between Chiasmolithus and Sullivania through the Paleocene. Change of most other morphocharacters occurs at variable rates and reversals in trends are common. Minimal correlation exists between the trends and oscillatory shape changes observed at the two sites. We conclude that these trends and oscillations represent local, transitory ecophenotypic variation of the complex form. There is little stasis in the ten-million-year record studied. Article in Journal/Newspaper Antarc* Antarctica North Atlantic Weddell Sea Cambridge University Press Weddell Sea Weddell Paleobiology 22 3 352 385 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Paleontology General Agricultural and Biological Sciences Ecology Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Paleontology General Agricultural and Biological Sciences Ecology Ecology, Evolution, Behavior and Systematics Bralower, Timothy J. Parrow, Matthew Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history |
topic_facet |
Paleontology General Agricultural and Biological Sciences Ecology Ecology, Evolution, Behavior and Systematics |
description |
Investigation of the evolution of calcareous nannoplankton is hindered by the extremely small size (5-10 μm) of their fossils. We introduce new technology, a scanning electron microscope connected to an image analysis system (SEM-IAS), which allows this field to be explored as never before. This system enables a host of morphocharacters to be measured and included in studies of phylogeny and evolutionary dynamics. We have applied the SEM-IAS to study the evolution of Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania. A variety of detailed measurements have been made on over 4000 coccoliths from Deep Sea Drilling Project Site 384 in the temperate North Atlantic and Ocean Drilling Program Site 690 in the Weddell Sea off Antarctica. Our results indicate no simple relationships between morphocharacters, the shapes of all three genera are both complex and highly variable. Although most morphocharacters possess little phylogenetic significance, the areas of different shield cycles show gradual divergence between Chiasmolithus and Sullivania through the Paleocene. Change of most other morphocharacters occurs at variable rates and reversals in trends are common. Minimal correlation exists between the trends and oscillatory shape changes observed at the two sites. We conclude that these trends and oscillations represent local, transitory ecophenotypic variation of the complex form. There is little stasis in the ten-million-year record studied. |
format |
Article in Journal/Newspaper |
author |
Bralower, Timothy J. Parrow, Matthew |
author_facet |
Bralower, Timothy J. Parrow, Matthew |
author_sort |
Bralower, Timothy J. |
title |
Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history |
title_short |
Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history |
title_full |
Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history |
title_fullStr |
Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history |
title_full_unstemmed |
Morphometrics of the Paleocene coccolith genera Cruciplacolithus, Chiasmolithus , and Sullivania : a complex evolutionary history |
title_sort |
morphometrics of the paleocene coccolith genera cruciplacolithus, chiasmolithus , and sullivania : a complex evolutionary history |
publisher |
Cambridge University Press (CUP) |
publishDate |
1996 |
url |
http://dx.doi.org/10.1017/s009483730001633x https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S009483730001633X |
geographic |
Weddell Sea Weddell |
geographic_facet |
Weddell Sea Weddell |
genre |
Antarc* Antarctica North Atlantic Weddell Sea |
genre_facet |
Antarc* Antarctica North Atlantic Weddell Sea |
op_source |
Paleobiology volume 22, issue 3, page 352-385 ISSN 0094-8373 1938-5331 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s009483730001633x |
container_title |
Paleobiology |
container_volume |
22 |
container_issue |
3 |
container_start_page |
352 |
op_container_end_page |
385 |
_version_ |
1792506545178673152 |