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Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria
Published on: July 24, 2016
Oxygen as a driver of early arthropod micro-benthos evolution
Mark Williams1, Jean Vannier, Laure Corbari
1Department of Geology, University of Leicester, Leicester, United Kingdom. mri@le.ac.uk
Plos One
|December 14, 2011
Summary
Ostracods became dominant marine micro-benthos by adapting to varying oxygen levels, unlike other arthropods that thrived in specific oxygen conditions. Their physiological and lifestyle adaptations allowed them to tolerate oxygen fluctuations throughout the Phanerozoic. Keywords: ostracods, marine micro-benthos, oxygen levels, adaptations, Phanerozoic.
Area of Science:
- Paleontology
- Marine Biology
- Evolutionary Biology
Background:
- Ostracods emerged as the dominant Phanerozoic bivalve arthropod micro-benthos.
- Physiological and lifestyle adaptations facilitated this dominance.
Purpose of the Study:
- To examine the adaptations of ostracods.
- To understand their rise to numerical dominance in the Phanerozoic micro-benthos.
Main Methods:
- Analysis of physiological adaptations to oxygen levels.
- Examination of lifestyle adaptations.
- Interrogation of the Cambrian fossil record of bivalve arthropod micro-benthos.
Main Results:
- Modern normoxic seawater PO(2) (21 kPa) causes cellular damage to marine fauna; cellular PO(2) is typically 1–3 kPa.
- Ostracods avoid oxygen toxicity via migration to hypoxic waters or high O(2) metabolism.
- Cambrian seawater PO(2) varied (10–30 kPa), influencing arthropod evolution: Bradoriida favored oxygenated waters, Phosphatocopida adapted to hypoxia, and Ostracods tolerated fluctuations, leading to their dominance.
Conclusions:
- Seawater oxygen levels significantly controlled marine ecosystem evolution.
- Ostracods' tolerance to oxygen variability drove their Phanerozoic micro-benthos dominance.
- Understanding oxygen's role in marine ecosystems provides evolutionary context for behavior.
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