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| Titel |
Anti-predation strategy, growth rate and extinction amongst Pliocene scallops of the US eastern seaboard |
| VerfasserIn |
Andrew Johnson, Annemarie Valentine, Melanie Leng, Hilary Sloane, Bernd Schöne, Donna Surge |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250151738
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| Publikation (Nr.) |
 EGU/EGU2017-16494.pdf |
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| Zusammenfassung |
| Placopecten, Chesapecten and Carolinapecten are scallop (pectinid bivalve) genera
occurring in the Pliocene of the US eastern seaboard. The first, present in the area
today, is a smooth, streamlined form, adept at escaping predators by swimming
(‘flight’ strategy). The other two, which are extinct, are plicate (‘ribbed’) forms.
Plication facilitates a ‘resistance’ strategy towards predators which is benefited by large
size and high shell thickness - maximally so if these states are achieved early in
life. Oxygen isotope profiles show that early ontogenetic extensional growth in
Pliocene Placopecten was at the same moderate rate as in modern Placopecten. By
contrast, in Chesapecten it was as fast as in the fastest-growing modern scallop (c. 80
mm/annum), and accompanied by development of an unusually thick shell, while in
Carolinapecten it was substantially faster still (<150 mm/annum). Rapid growth in
Chesapecten and Carolinapecten was probably enabled by high primary productivity, for
which there is evidence from sediment composition and the associated biota. The
extinction of Chesapecten and Carolinapecten, and the survival of Placopecten, can be
attributed to a decline in primary productivity which prevented a maximally effective
‘resistance’ strategy towards predators but had no deleterious impact on a ‘flight’ strategy. |
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