- 23 December 2010
- Magazine issue 2792.
GENE families involved in respiration and photosynthesis arose in a short evolutionary burst that began nearly a billion years before Earth's atmosphere became rich in oxygen.
Lawrence David and Eric Alm from the Massachusetts Institute of Technology mapped the evolutionary history of 3983 gene families that occur in a wide range of modern species. They were able to show that 27 per cent of these gene families appeared in a short evolutionary burst which began about 3.3 billion years ago (Nature, DOI: 10.1038/nature09649).
Many of the genes from this time were involved in electron transport - a key step in respiration and photosynthesis, which ultimately led, say David and Alm, to oxygen-producing photosynthesis and the "great oxygenation event" 2.4 billion years ago, when the atmosphere became oxygen rich.
