Unplanned Functional Decline

No one’s yet demonstrated
That the maximum lifespan
Of a vertebrate can be

Radically extended.
Of course, everyone trying
And everyone watching them

Is a vertebrate thinking
Maybe just maybe their own
Lifespan might be extended.

Meanwhile, the couple dozen
Supercentennarians
Breathe while they can keep breathing,

And everyone keeps aging
To the temporal limit,
And no one over the age

Of one-fifteen, not even
Jeanne Calment, writes anything,
Much less something worth reading.