Ars Technica gets a first glimpse at the language of cephalopods, with the discovery that each octopus (which can change the pattern of its skin at will) has its own unique pattern of stripes that says, “This is me”:
The UC Berkeley researchers studying the lesser Pacific striped octopus (also called the zebra octopus, Octopus chierchiae), found that the animals’ striping patterns seemed to be individualized, similar to our fingerprint patterns. As this small cephalopod has previously been recommended as a new model organism for future studies, having these octopus “fingerprints” could help to solidify O. chierchiae’s place as the poster child for cephalopod research.
“Originally, we were just trying to figure out how to breed them in captivity, but we noticed that all of the individuals looked different, and we could easily identify them by their stripe patterns, even if they escaped from their labeled jars into the larger tank,” explained researchers Benjamin Liu, Leo Song, Saumitra Kelkar, and Anna Ramji. “Dr. Roy Caldwell, our mentor and the PI [principal investigator] of the lab, recommended that we investigate whether this could be useful to the study of this species.”
As the team explained: “Dr. Christine Huffard, one of Caldwell’s former graduate students, led a study on the unique body patterns of Wunderpus photogenicus, an Indo-Pacific octopus species. In that paper, the authors showed that the body patterns of adult octopuses remain constant in aquaria and captured photos that appear to show the same individual octopus in the wild many months apart.”
While raising a new clutch of O. chierchiaes, the team found similarities to what Huffard had seen. “We noticed that the baby octopuses we were raising seemed to retain the same stripe patterns from the age that the stripes are first visible—the stripe pattern never shifted, it just grew proportionally to the animal, in every baby octopus we raised and observed,” they added. “We thought this was interesting and worth reporting, and possibly useful for the potential study of this species’ life history and ecology in the wild.”
The UC Berkeley researchers looked at 25 of the 156 octopuses that they had in the laboratory and were able to photograph their striping patterns. While the patterns didn’t appear until day five of the hatchling’s existence, these stripes would stay with them throughout their life. “The dominant stripes are landmarks on the skin,” explained Dr. Z Yan Wang, an assistant professor of biology at the University of Washington. “They are dynamic in the sense that they can get darker or lighter. But as far as we know, the particular stripes themselves are permanent.”
You can read more of the Berkeley team’s research here, in PLOS One.