A final fixed form is death

(written by lawrence krubner, however indented passages are often quotes). You can contact lawrence at: lawrence@krubner.com, or follow me on Twitter.

Lost in my last post was this sentence:

Candidate organisms include perennial trees and modular organisms like sponges which can reproduce both sexually and asexually, but also sexually reproducing vertebrates that continue somatic growth after maturation, like fish and turtles.

That seems to sum it up. Creatures that continue to grow forever, like fish and turtles, also seem able to live forever. But creatures that grow old, like elephants and birds and humans, have a final, fixed, mature form, and its this fixed, unchanging form that kills them. In these creatures, when growth finally resumes in old age, it is of a deadly kind: cancer, cells which have stopped heeding the command to remain still in their fixed, frozen state.

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