The Editor of Itself

On the sixth morning, Chiara made coffee for both of them and sat down beside the tank. Pasta was hanging upside down from a corner of the glass. Her body bell pulsed gently. Her arms drifted around her like a slow flower.

På den sjette morgen lavede Chiara kaffe til dem begge og satte sig ved siden af akvariet. Pasta hang på hovedet fra et hjørne af glasset. Hendes kropspuls boblede blidt. Hendes arme svævede omkring hende som en langsom blomst.

"There is one more thing I want to tell you," Chiara said, "and I want to tell it slowly, because it is the strangest thing about octopuses I know."

"Der er en ting mere, jeg vil fortælle dig," sagde Chiara, "og jeg vil fortælle det langsomt, for det er det mærkeligste ved blæksprutter, jeg kender."

Polly perched on the rim.

Polly satte sig på kanten.

"Octopuses can edit their own RNA in real time," Chiara said. "No other animal does this at the rate they do."

"Blæksprutter kan redigere deres egen RNA i realtid," sagde Chiara. "Ingen andre dyr gør dette i samme tempo."

DNA is the long-term blueprint of an animal. It does not change much in a lifetime. RNA is the working copy. The cell makes RNA from DNA when it needs to build a protein. In most animals, the RNA matches the DNA exactly.

DNA er et dyrs langsigtede plan. Det ændrer sig ikke meget i løbet af et liv. RNA er den arbejdskopi. Cellen laver RNA fra DNA, når den skal bygge et protein. Hos de fleste dyr matcher RNA præcis DNA.

In octopuses, the RNA does not match. As the RNA is being made, the cell rewrites parts of it. Most of these edits happen in the parts that build the nervous system.

Hos blæksprutter matcher RNA ikke. Mens RNA bliver lavet, omskriver cellen dele af det. De fleste af disse redigeringer sker i de dele, der bygger nervesystemet.

"Why?" Chiara said. "RNA editing is reversible. DNA mutation is not. An octopus can adjust its nervous system in response to the temperature of the water or the chemistry of its food. It tunes its own brain. The cost is that the species itself has not been able to evolve much. They paid for short-term flexibility with long-term stability."

"Hvorfor?" sagde Chiara. "RNA-redigering er reversibel. DNA-mutation er ikke. En blæksprutte kan justere sit nervesystem som reaktion på vandets temperatur eller kemien i dens mad. Den finjusterer sin egen hjerne. Prisen er, at arten ikke har været i stand til at udvikle sig meget. De har betalt for kortsigtet fleksibilitet med langsigtet stabilitet."

Pasta drifted. Her skin near the eyes flickered through soft pinks and pale browns.

Pasta svævede. Hendes hud nær øjnene flimrede gennem bløde lyserøde og lysebrune nuancer.

"Each individual octopus," Chiara said, "is a slightly different animal from every other one, in a way that you and I and other parrots are not. The same DNA, but the working machinery is built fresh, every life, for that water and that food."

"Hver enkelt blæksprutte," sagde Chiara, "er et lidt anderledes dyr end alle andre, på en måde som du og jeg og andre papegøjer ikke er. Det samme DNA, men det arbejdende maskineri bygges frisk, hvert liv, til det vand og den mad."

Polly thought about her own brain. It had been built once, the way most brains are built, and was now simply hers. She did not envy Pasta the flexibility. But she liked very much knowing that animals like Pasta existed.

Polly tænkte på sin egen hjerne. Den var blevet bygget én gang, som de fleste hjerner bliver, og var nu simpelthen hendes. Hun misundte ikke Pasta fleksibiliteten. Men hun kunne godt lide at vide, at dyr som Pasta eksisterede.