The study of aging is an ongoing project, as is the study of cellular metabolism. The research community remains some way from a complete understanding, and as such there is a great deal of ongoing empirical discovery. Popular areas of study exist because someone demonstrated that a particular approach to therapy produced a slowing or reversal of measurable aspects of aging. Others then join in to try to understand how it works. None of these existing approaches are yet fully understood, in part because they produce complex changes in complex systems. Layered atop considerations of aging in laboratory mice and humans is the point that the world contains thousands of species that researchers might plausibly study, many of which exhibit quite different patterns of aging or specific aspects of aging biology. There is more complexity than can be engaged with in any reasonable amount of time, but discoveries made in recent decades suggest that there is the potential to find useful new approaches to the treatment of aging by comparing different species. It just won't happen quickly.
Despite still being an emerging field of research, biogerontology has made remarkable progress in identifying molecular principles of cellular aging over the last two decades. The categorization of these principles into "hallmarks of aging" has proven useful, as experimental modulation of these hallmarks in various model organisms can alter aging trajectories. In nature, we encounter remarkable variation in lifespan and demographic aging across individuals, species, populations, and space. Why has this variability evolved? Do the same "hallmarks of aging" identified as important in laboratory animals explain this variation? How do the molecular processes shaping aging vary across species and environmental conditions? What role do developmental processes and conditions play in shaping the onset and rate of aging across species? These fundamental questions remain largely unanswered. Yet, they are critical not only for advancing the biology of aging but also for designing interventions to mitigate age-related decline.
Understanding why particular pathways or hallmarks matter in specific taxa, and how developmental processes interact with environmental constraints to shape aging, requires synthesizing and comparing mechanisms identified in classical model organisms with those discovered in non-model species spanning broad phylogenetic and ecological contexts. Many evolutionary theories of aging were proposed well before the discovery of the molecular mechanisms involved, and they remain largely theoretical. Moreover, the growing number of model organisms and the expanding array of experimental and theoretical approaches used to study aging have often remained compartmentalized. As a result, integrating these diverse insights into a unified framework has become increasingly important. As a step toward this goal, this field perspective outlines general biological mechanisms that help explain the variability in aging patterns and longevity across the animal kingdom.
Link: https://doi.org/10.1038/s44318-026-00725-z
View the full article at FightAging
