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NASA NTRS · 20040112174

The influence of UV radiation on protistan evolution

Rothschild, L. J.
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Abstract

Ultraviolet radiation has provided an evolutionary challenge to life on Earth. Recent increases in surficial ultraviolet B fluxes have focused attention on the role of UV radiation in protistan ecology, cancer, and DNA damage. Exploiting this new wealth of data, I examine the possibility that ultraviolet radiation may have played a significant role in the evolution of the first eukaryotes, that is, protists. Protists probably arose well before the formation of a significant ozone shield, and thus were probably subjected to substantial ultraviolet A, ultraviolet B, and ultraviolet C fluxes early in their evolution. Evolution consists of the generation of heritable variations and the subsequent selection of these variants. Ultraviolet radiation has played a role both as a mutagen and as a selective agent. In its role as a mutagen, it may have been crucial in the origin of sex and as a driver of molecular evolution. As a selective agent, its influence has been broad. Discussed in this paper are the influence of ultraviolet radiation on biogeography, photosynthesis, and desiccation resistance.

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NASA Center ARCNASA Discipline ExobiologyEvolutionUltraviolet RaysEukaryotic Cells/radiation effectsProkaryotic Cells/radiation effectsMutationMarsDNA DamageDNA RepairPhotosynthesisSexAnimalsEvolution, Molecular

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Rothschild, L. J.. 1999-09-01. The influence of UV radiation on protistan evolution. https://ntrs.nasa.gov/citations/20040112174

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