Articles | Volume 22, issue 2
https://doi.org/10.1144/jm.22.2.141
© Author(s) 2003. This work is distributed under the Creative Commons Attribution 4.0 License.
01 Nov 2003
| 01 Nov 2003
Coiling direction in Globigerina bulloides of Middle Miocene age
Abstract. Detailed analysis of the early evolutionary stage of Globigerina bulloides in Middle Miocene calcareous nannoplankton zones NN5 and NN6 shows no preference for sinistral or dextral coiling patterns despite seawater temperature variations (as inferred from stable isotope analyses of foraminifer shells). Accordingly, coiling direction was proportional or biased to sinistral.
