Response to comment on ’Naked mole-rat mortality rates defy gompertzian laws by not increasing with age’

Research output: Contribution to journalLetter


External Institution(s)

  • Calico Life Sciences LLC


Original languageEnglish (US)
Article numbere47047
StatusPublished - Jul 2019


For most adult mammals, the risk of death increases exponentially with age, an observation originally described for humans by Benjamin Gompertz. We recently performed a Kaplan–Meier survival analysis of naked mole-rats (Heterocephalus glaber) and concluded that their risk of death remains constant as they grow older (Ruby et al., 2018). Dammann et al. suggest incomplete historical records potentially confounded our demographic analysis (Dammann et al., 2019). In response, we applied the left-censorship technique of Kaplan and Meier to exclude all data from the historical era in which they speculate the records to be confounded. Our new analysis produced indistinguishable results from what we had previously published, and thus strongly reinforced our original conclusions.