Lifespan - Octopus Optic Gland and More

Discussion in 'Physiology and Biology' started by DWhatley, May 20, 2010.

  1. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    A collection of links to articles and abstracts about octopus optic gland studies.


    Optic glands and the state of the testis in Octopus - 1972 - abstract free, article subscription or pay for view

    OPTIC GLAND IMPLANTS AND THEIR EFFECTS ON THE GONADS OF OCTOPUS - 1974 - Full PDF

    Additional Lifespan Posts
    Octopus senescence on the cellular level

    Optic glands in octopuses

    Seasonal Pattern to Octopus Deaths

    Senescence The Beginning of the End

    Study on Octopus Aging

    Pre-senescence aging

    Nervous control of reproduction in Octopus vulgaris: a new model
    C Di Cristo - Invertebrate Neuroscience, 2013
     
  2. Level_Head

    Level_Head Vampyroteuthis Registered

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    You could make a story out of this ... ;)

    This article downplays somewhat the effect on males. Later studies addressed that issue.

    The optic glands are wired into the eyes to pick up lighting signals from the environment. Incidentally, that article indicates that changes in lighting condition -- such as the cues accidentally provided by a new tank's different light setup -- can be enough to trigger the optic gland's operation. This would result in sexual maturity and egg laying some weeks after the lighting change.

    That sounds sadly familiar.
     
  3. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    Do you have a link to the article about lighting, if it goes into detail about the kind of lighting that produced changes, I would very, very much like to read it.
     
  4. Level_Head

    Level_Head Vampyroteuthis Registered

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    From your second link (the full PDF):
    Both of these are suggestive, but the lighting seems to be a more universal trigger for optic glands.

    In fact, trigger is probably the wrong word. Rather than wrong lighting triggering optic glands into action, it's "natural" lighting that, for a time, keeps the optic glands from being triggered. So any loss of that signal -- cutting nerves to the optic gland, covering or disabling the eyes of the octopus -- any of that removes the inhibition and the optic glands start their work to bring about sexual maturity and (in females) egg-laying quickly.

    It is the change in length of daylight hours that is supposed to end the optic gland inhibition in the wild. So, it seems that the best approximation to the animal's normal lighting period might be the safest approach.

    In fact, keeping the daytime period to simulate the time of year before sexual maturity begins might be the best approach. I haven't seen a paper that explicitly tries this, but it seems logical as an extending technique.
     
  5. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    Brain Is Command Center for Aging - sound familiar?

    OctopussyAZ posted a link on Facebook referencing several new science finds, this one was subtitled:

    Inflammation in the hypothalamus may induce degeneration in tissues throughout the body

    Reading the linked layman's summary in The Scientist I could not help but think of the similarities of the function of the hypothalamus and the optic gland in respect to aging and maturing.
     
  6. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    Thoughts on Low Egg Production and Post Brood Longevity

    I have wondered about the possibility of the number of eggs produced affects longevity after hatching (albeit, not an extensive extension) for the female octopus. It has occurred to me that something as simple as the eggs pushing on the digestive system might interfere with nutrition intake.

    The thoughts started with my own observation with Trapper (O. mercatoris) who only produced 6 hatchlings and survived an additional 11 weeks.

    The chierchiae octopus produces small clutches and is one of only two we know of that survives hatching and can produce an additional clutch.


    The Island Bay Marine Education Center (Wellington, NZ) noted a similar occurrence:
     
  7. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    [h=1]Coccidian infection may explain the differences in the life history of octopus host populations [/h] Lorena P. Storero, Maite A. Narvarte August 2013
    [h=2]Abstract[/h] The prevalence of coccidian parasites in three Octopus tehuelchus populations from San Matías Gulf (Patagonia, Argentina) is compared. The prevalence was similar between sexes, but varied between seasons (being highest during cold months) and sites. Islote Lobos had the highest prevalence (42.7–100%) followed by San Antonio Bay (0–66%) and El Fuerte (0–24.5%). Octopuses under 27 mm of dorsal mantle length showed a low prevalence (less than 50%), which increased with size. We hypothesize that the high prevalence of parasites, which affect the three populations differentially, could account for the observed variability in life-span and growth, size–frequency distributions, reproduction and densities of O. tehuelchus populations.
     
  8. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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  9. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    Hormonal inhibition of feeding and death in octopus: control by optic gland secretion Jerome Wodinsky 1977
    Science 2 December 1977:
    Vol. 198 no. 4320 pp. 948-951DOI:10.1126/science.198.4320.948 (subscription)


    Note: This abstract declares that removal of the optic gland AFTER brooding slows reverses some of the senescence properties and the animal begins feeding and growing again. Prior studies noted that the removal must be done before sexual maturity.

     
    Last edited: Dec 19, 2013
  10. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    A study on the optic glands of Sepioteuthis lessoniana from the Red Sea
    Waheed M. Emam and Tarek G. Ali 2014 (pdf)

    Work done on dead squid but includes an interesting note about removing O. vulgaris optic gland and implanting octopus and squid glands where the gland from other octopuses continued to develop and the squid optic gland did not.

     
  11. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    THE PARASITES OF CEPHALOPODS: A REVIEW
    F. G. Hochbe 1983 (pdf)

     
  12. DWhatley

    DWhatley Cthulhu Staff Member Moderator

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    Stylet weight as a proxy for age in a merobenthic octopus population
     

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