The Editor of Itself

On the sixth morning, Chiara made coffee. She sat by the tank with Polly.

Pasta was hanging upside down. Her body pulsed slowly. Her arms drifted.

"I want to tell you one more thing," Chiara said. "It is the strangest thing I know about octopuses."

DNA is the long-term plan of an animal. RNA is the working copy.

In most animals, the RNA matches the DNA. But in octopuses, the RNA does not match. The cell rewrites parts of the RNA as it makes it. Most of the edits happen in the nervous system.

"Why?" Chiara said. "It lets the octopus change its nervous system. It can tune its own brain to the water temperature or to its food."

Pasta drifted. Her skin near the eyes turned soft pink and brown.

"Each octopus is a slightly different animal," Chiara said. "Same DNA. But the working machinery is built fresh, for that water and that food."

Polly thought about her own brain. It was hers. She did not want it to change. But she liked knowing that animals like Pasta existed.