The bacterium
"Until recently, people thought that bacteria cannot age," said Martin Ackermann, of the ETH Zentrum, who was not involved in the study. "Then, we published this paper showing aging in bacteria with asymmetric division. The next question was if a visible morphological asymmetry was necessary or whether all bacteria could age. This new paper suggests that aging can actually be found in all bacterial cells, maybe in all living cells."
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