I can’t believe that is a real species name.
I’ll be up for hearing others that make you crack a smile.
Apparently one can track an individual octopus of this species by simply recording its unique pattern of white spots on its back on camera, and these don’t change over time. Much like for whales and their battle scars.
Each animal bore a circular pattern of approximately six white spots in the center of the mantle. However fusions of these spots and the location of additional small markings in this region differed among individuals. Lateral markings also appeared to vary asymmetrically.
My attention was drawn to this article because I’ve been cogitating my next pigment-related post. I’m actually not intellectually that interested in pigment cell or skin biology, but I have a vested personal interest and in vertebrates at least, they do come from my favorite developmental cell type, the neural crest cell.
However, the octopus is not a vertebrate, as cuddly and smart as it is.
Even I can’t get access to this article but the abstract is fairly informative: the octopus has organs called “chromatophores” which contain different kinds of pigment, and are under neuromuscular control. This enables them to change patterns and camouflage with their environment. They overlie “iridophores” which provide a kind of iridescent, mirror-like light-reflecting surface over which the different colors are deployed like filters.
I don’t know if the white markings of Wunderpus photogenicus are simply the lack of colored pigment in those areas, or a concentration of a special sort of iridophore, or both. I would speculate it is the same sort of thing that keeps their sex organs white – as mentioned by those authors, collagen arrangements in the skin can have a high refractive index (think of the tendons in a leg of chicken).
So, as a developmental biologist, looking at this animal makes me think of a few things:
- is the genetic mechanism for alternative white and dark patches on the legs related to that which enables the periodicity of segments?
- how do they get personalized patterns on their backs? And why white? Can the chromatophores cover them up?
- isn’t it sort of dangerous to attract predator attention to external sex organs?
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Later edit: Thanks to Bob, I was able to access the large article by J.B. Messenger entitled Cephalopod chromatophores: neurobiology and
natural history.
The white pigment is from a dedicated cell type, the leucophore:
Most loliginid squids lack leucophores and complete retraction of the chromatophores produces instead the transparency that can be so important for camouflage in epipelagic animals. [Leucophores] are elongated, flattened cells, approximately 20 um long, covered with over 1000 tiny, stalked `knobs’, the leucosomes. They are colourless
but refractile, the leucosomes scattering light to
produce the chalky whites seen in incident white light. {…} It should be recalled, however, that the leucophores will faithfully reflect incident light across the entire visible spectrum and that the so-called ‘white’ areas will appear blue in blue light or red in red light. This may enable the skin to match the hue of the background as well as its brightness.
What a lovely new word for me, loliginid.
Not so. You drop subtle hints in a blog post, and then someone fills your inbox. :-)
I love the name too. How can any other octopus compete?
Thank you! There is, for information purposes, another goodwill-based resource for obtaining articles one can’t otherwise.
Still requesting silly species names…
Still requesting silly species names
Look no further.
One of my favorites is that for the Eurasian Hoopoe, Upupa epops. I think the genus name is onomatopoeic for the bird’s call, but I’m not sure about the epops. Also funny because of the hoopoe’s nest defense strategy: a house so filthy and bepooped that even Kim and Aggie would refuse to enter.
We’ve got those in our backyard again as of recently. I find them delightfully foreign. (Then again, I waxed excited about the gray heron and the dormouse, the latter of which seems to have elected residence in our garret.)
I thought lapwings were pretty exciting, when I lived in England. And birds that I find rather ordinary here (Scissor-tailed Flycatchers, Roadrunners, Crested Caracaras, Vermillion Flycatchers) are “life” birds for some of my visiting friends.
I always liked Gorilla gorilla gorilla. I think it’s some kind of monkey.