DWhatley;179173 said:

Later work found that removal of the optic gland extended the octopuses lives Click to expand... (Hoping Level Head will jump in here as I know he has read the later work and may have a ready reference). From what I remember, not only can the gland be removed and stop sexual maturity but a small piece can be reintroduced and will start up the reproductive cycle. On rereading the article, this comment was interesting and I wonder if anyone has experimented with the light aspect:(Hoping Level Head will jump in here as I know he has read the later work and may have a ready reference). From what I remember, not only can the gland be removed and stop sexual maturity but a small piece can be reintroduced and will start up the reproductive cycle. Click to expand...

# Removal of the optic gland and bright light prevent sexual maturation of these animals. Click to expand...

You've covered the ground well, it seems. There is a good collection of references on this thread:On the light aspect, your first outline contained an interesting line:I've read suggestions that the timing of the light is likely to influence the optic gland, but this was the first time I'd see this idea: that bright light keeps it from maturing.Is that "all the time"? 24 hours? What effect does that have on the animal's lifespan?I'm still jamming on a project, but that's worth some studies.You and I have discussed the possibility that tank lighting may be responsible for the shorter-than-natural lifespans of some octopuses in captivity.The antigen aspect was interesting, too; the idea that the optic gland is tied in to the immune system in some manner, such that the optic gland starts secreting in reaction to foreign proteins in the animal's blood.That work was done decades ago, and our molecular capability has dramatically improved since then, but I haven't seen an update.To address SquidInk's original question, I note that some researchers suggested that it was rapid metabolism that caused the short lifespan -- and we now know that this isn't completely true, since we can shorten or extend that lifespan without changing the metabolic rates.It is apparently a literal case of planned obsolescence. Or, in this case, programmed senescence.I hold out hope that evolution can make changes here. After all, a fairly close relative of the octopus (the geoduck clam) is known to live for nearly two centuries While we don't think of clams and cephalopods as close, the metabolism at the cellular level is in some ways more alike than different. And their body plans have surprising similarities.