Rhinos do not die of old age. No critter in the Wild does. We each press on until something interferes with our activities. If We avoid predation or hunger or disease or accident, We still will face a time when We can no longer eat enough to keep going.
Then We are recycled. That is how it is in the Wild. It seems a perfectly planned system to Us. Knowing all that makes it clear to each of Us that our time is finite.
It also makes it clear that We each will go in an elegant way; We will be useful no matter what. Naturally.
We find that awareness comforting.