Evolutionary Mystery of Nuclei (IMAGE) Tokyo University of Science Caption DNA exchange between ancient giant viruses and ancient biological cells might have been the key to the evolution of nuclei in eukaryotic cells Credit Tokyo University of Science Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.