Senescence, Telomeres, and Life history Trade-offs

Abstract

AbstractWe began with birth, and we arrive at old age. How well do Shakespeare’s ‘Seven Ages of Man’ match the badger’s reality? We explore the sex steroid profile of badgers throughout their lives, documenting how these steroids ebb with age, but that a subset of elderly individuals remain fertile. Meanwhile, curiously for a wild animal, a remaining proportion lives on in post-reproductive condition. This leads us to senescence and questions about what goes wrong, or impedes repair, at the cellular level, and the puzzle of why badgers, like most other larger mammals, don’t make telomerase continuously, regenerate their telomeres, and avoid cellular senescence. Interestingly, we find that badger telomeres get longer in meline middle age. Why? And in this chapter, as in others, we find that it’s the start each individual gets in life that counts. Why should cubs experiencing tough times early in life, linked again to inclement weather, have longer telomeres? The answer leads to a comparison of different preparations for life.