The Darwinist reasoning behind rates of aging goes something like this. A adult mouse has a high chance of being killed in a random year (above 20%) a Parrot has a low chance (below 3%). Maintaining a body into old age has a cost that reduces reproductive capability in a given year and a benefit of increasing the number of years of reproductive capability. There are also minimums of capability in the wild where vision and mobility link to survival rates such that there are thresholds below which rates of survival dramatically decrease.
Thus, the number of healthy years in the wild relates to both the probability of an external death AND internal heath issues. For a mouse this suggests a minimum of internal maintenance for maximum reproduction where a parrot can make significant trade-offs in reproduction in order to live 10x as long and have more long term reproductive chances.
However, that's in the natural setting. A pet (mouse, cat, parrot) can live slightly longer in captivity by surviving pat the point where it can find food for it's self. If you look a human vision decline people are significantly less capable of surviving on their own before they lose reproductive capability. And in that "unnatural" old age it's not uncommon for various species to have increasing reproductive issues.
Thus, the number of healthy years in the wild relates to both the probability of an external death AND internal heath issues. For a mouse this suggests a minimum of internal maintenance for maximum reproduction where a parrot can make significant trade-offs in reproduction in order to live 10x as long and have more long term reproductive chances.
However, that's in the natural setting. A pet (mouse, cat, parrot) can live slightly longer in captivity by surviving pat the point where it can find food for it's self. If you look a human vision decline people are significantly less capable of surviving on their own before they lose reproductive capability. And in that "unnatural" old age it's not uncommon for various species to have increasing reproductive issues.