Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

Journal of Paleontology

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (11) Citing Articles via Google Scholar Google Scholar Articles by BEU, A. G. Search for Related Content GeoRef GeoRef Citation

GRADUAL MIOCENE TO PLEISTOCENE UPLIFT OF THE CENTRAL AMERICAN ISTHMUS: EVIDENCE FROM TROPICAL AMERICAN TONNOIDEAN GASTROPODS

¹ Institute of Geological and Nuclear Sciences, P O Box 30368, Lower Hutt, New Zealand, <a.beu{at}gns.cri.nz>

Tonnoidean gastropods have planktotrophic larval lives of up to a year and are widely dispersed in ocean currents; the larvae maintain genetic exchange between adult populations. They therefore are expected to respond rapidly to new geographic barriers by either extinction or speciation. Fossil tonnoideans on the opposite coast of the Americas from their present-day range demonstrate that larval transport still was possible through Central America at the time of deposition of the fossils. Early Miocene occurrences of Cypraecassis tenuis (now eastern Pacific) in the Caribbean probably indicate that constriction of the Central American seaway had commenced by Middle Miocene time. Pliocene larval transport through the seaway is demonstrated by Bursa rugosa (now eastern Pacific) in Caribbean Miocene-latest Pliocene/Early Pleistocene rocks; Crossata ventricosa (eastern Pacific) in late Pliocene rocks of Atlantic Panama; Distorsio clathrata (western Atlantic) in middle Pliocene rocks of Ecuador; Cymatium wiegmanni (eastern Pacific) in middle Pliocene rocks of Atlantic Costa Rica; Sconsia sublaevigata (western Atlantic) in Pliocene rocks of Darien, Pacific Panama; and Distorsio constricta (eastern Pacific) in latest Pliocene-Early Pleistocene rocks of Atlantic Costa Rica. Continued Early or middle Pleistocene connections are demonstrated by Cymatium cingulatum (now Atlantic) in the Armuelles Formation of Pacific Panama. Tonnoideans indicate that the Central American seaway began to be constricted after early Miocene time, and some larval transport through the seaway was possible throughout Pliocene time. Intermittent marine connections were maintained at least during late Pliocene to early Pleistocene interglacial periods of high sea-level, and alternated with a land bridge during glacial periods of low sea-level.

This article has been cited by other articles:

				G. J. Vermeij One-way traffic in the western Atlantic: causes and consequences of Miocene to early Pleistocene molluscan invasions in Florida and the Caribbean Paleobiology, December 1, 2005; 31(4): 624 - 642. [Abstract] [Full Text] [PDF]

				P. B. Marko Fossil Calibration of Molecular Clocks and the Divergence Times of Geminate Species Pairs Separated by the Isthmus of Panama Mol. Biol. Evol., November 1, 2002; 19(11): 2005 - 2021. [Abstract] [Full Text] [PDF]