Suresh I. S. Rattan's editorial highlights seven key knowledge gaps in modern biogerontology, categorized into three main areas: evolutionary aspects of longevity, biological survival and death, and heterogeneity in the progression and phenotype of ageing. These gaps reflect ongoing challenges in understanding the biological mechanisms of ageing and longevity. The article discusses the limitations in identifying genes and pathways responsible for longevity, the evolutionary explanations for the species-specific essential lifespan (ELS), and the complexity of biological time and its regulation. It also addresses the heterogeneity of the ageing phenotype, the accumulation of molecular damage, and the need for a better understanding of the adaptive responses to age-related changes. The editorial emphasizes the importance of shifting research focus from disease treatment to health maintenance and the need for interdisciplinary approaches to address these knowledge gaps. It also warns against overhyped claims in anti-ageing research and stresses the importance of considering the biphasic dose response of hormesis in interventions. The article concludes that these knowledge gaps have significant implications for both basic research and the development of effective strategies for healthy ageing and longevity.Suresh I. S. Rattan's editorial highlights seven key knowledge gaps in modern biogerontology, categorized into three main areas: evolutionary aspects of longevity, biological survival and death, and heterogeneity in the progression and phenotype of ageing. These gaps reflect ongoing challenges in understanding the biological mechanisms of ageing and longevity. The article discusses the limitations in identifying genes and pathways responsible for longevity, the evolutionary explanations for the species-specific essential lifespan (ELS), and the complexity of biological time and its regulation. It also addresses the heterogeneity of the ageing phenotype, the accumulation of molecular damage, and the need for a better understanding of the adaptive responses to age-related changes. The editorial emphasizes the importance of shifting research focus from disease treatment to health maintenance and the need for interdisciplinary approaches to address these knowledge gaps. It also warns against overhyped claims in anti-ageing research and stresses the importance of considering the biphasic dose response of hormesis in interventions. The article concludes that these knowledge gaps have significant implications for both basic research and the development of effective strategies for healthy ageing and longevity.