Wikipedia:Reference desk/Archives/Science/2012 May 3

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May 3

Who would and wouldn't want to live forever

Can psychologists ever say, with as much certainty as the experimental sciences ever give, whether or not a person would want to live forever given the choice (given that they aren't already attempting suicide)? If so, does this suggest a limit on the computational diversity of human minds (e.g. via the obvious argument involving mind uploading and the undecidability of the halting problem)? NeonMerlin 08:05, 3 May 2012 (UTC)

That needs some clarification. Would everybody be living forever? My dad outlived most of his peers, and declared that life became pretty boring because all his old friends were dead. HiLo48 (talk) 08:33, 3 May 2012 (UTC)

I don't think they would have studied it much given at this point that everyone dies or is expected to die. If you give people the option of unlimited lifespan at peak mental and physical health than the answer is going to be different to giving the option to extend life of a person in ever declining health. SkyMachine ⁽⁺⁺⁾ 08:51, 3 May 2012 (UTC)

I would like to live for a long time, but not forever. If you lived "forever", you would spend most of your time alone, floating in complete darkness because all the suns would have gone out and all atoms would have decayed. Zzubnik (talk) 10:02, 3 May 2012 (UTC)

You could always get around to try & replace the existing universe with a new one if it ends its usefulness. If a digital copy of a mind decided it did not want to continue then that mind can be replaced by an archived copy of the mind in a state that wanted to continue on. All the archive copies would have to be destroyed if a true and final end is sought. SkyMachine ⁽⁺⁺⁾ 10:07, 3 May 2012 (UTC)

It seems to me that how you handle memories would play a role here. If we retain the current limit on amount of memories, this means we would either need to stop memorizing new things or forget old things. Either one would be like having a form of dementia. StuRat (talk) 15:45, 3 May 2012 (UTC)

Say what? We forget old things all the time. We may not forget them completely, but details fade over time and are replaced with vague impressions that presumably take up less space. --140.180.5.49 (talk) 17:00, 3 May 2012 (UTC)

Right, but now say you live 1000 times longer. You'd then only remember 1/1000th as much of each year, on average. That's so little, most years would be lost entirely. StuRat (talk) 02:11, 4 May 2012 (UTC)

So at any given time your memories would be mostly of the last century or so. The "you" of a thousand years ago would be a stranger with whom you happen to share a number of quirks and talents. Would that knowledge make anyone prefer to die, wiping out all memories? —Tamfang (talk) 21:58, 6 May 2012 (UTC)

I regard myself as an immortalist. I want to live as long as possible. Maybe not literally forever, but as close as I can get. Abyssal (talk) 16:31, 3 May 2012 (UTC)

I bet what you're really saying is "I want to live as long as I can with a decent quality of life". Would you wish to have Stephen Hawking as a role model, for example? He has spent many of his 70 years with a form of MND. There is a Greek myth about a woman who asked for eternal life but forgot to ask for eternal youth. --TammyMoet (talk) 20:15, 3 May 2012 (UTC)

Tithonus, incidentally. Tevildo (talk) 21:31, 3 May 2012 (UTC)

See also the first paragraph of Cumaean Sibyl#Later literature for another classical example. Deor (talk) 22:44, 3 May 2012 (UTC)

Programmed death

Everyone dies so one can speak of a biological program for decay to death of the body's physical and mental functions that starts inevitably from the instant of birth. Is the rate of dying fastest while one is awake and active physically and mentally, or while one is sleeping?

This morbid question is prompted by the observation that some cells are programmed to die during early development of the embryo to open the spaces between fingers and toes, and a story by Edgar Allen Poe about a dying man kept alive by hypnosis. 84.209.89.214 (talk) 11:46, 3 May 2012 (UTC)

The only "biological program" that controls death and decay that I know of is telomere decay, which affects how many times your cells can duplicate and replace themselves, which puts a finite limit on your life as an organism. My guess is that being awake or asleep doesn't affect this too much on average; ditto active or sluggish. But I don't really know. There are a lot of other factors regarding whether one lives a long time or not beyond telomere decay — you only have to worry about your telomeres if nothing else gets you first! For most people, death comes a lot sooner than that. --Mr.98 (talk) 14:02, 3 May 2012 (UTC)

A bit off topic, but is there some study that has determined what percentage of people die simply of old age (i.e. not mayhem, accidents or disease)? Clarityfiend (talk) 23:45, 3 May 2012 (UTC)

Exercise and thinking involves burning blood sugar, which tends to cause oxidation aging damage to the cells. Anti-oxidants can help reduce this effect, but not eliminate it. A near starvation diet also limits the amount of oxidation (and exercise and thinking) your body can do. StuRat (talk) 14:59, 3 May 2012 (UTC)

This is largely the same debate as planned obsolescence, I think, except that the body of course was not "designed" to work or "planned" to fail in the quite the same sense. Wnt (talk) 15:39, 3 May 2012 (UTC)

But the result is the same, if evolution favors species with programmed death (since that allows for shorter generations and thus the ability to more quickly adapt to a changing environment). StuRat (talk) 15:42, 3 May 2012 (UTC)

There is also a cost/benefit tradeoff involved. Mechanisms that lead to eventual cell death may in the shorter term improve odds of survival (or perhaps reproduction). The net effect may be improved survival of the genome. I have in mind the fact that telomere decay is a primary defense of the body against cancer. Uncontrolled cell division due to genetic damage is a big problem. Telomeres are kind of a "dead man switch" that shuts down the process if other controls fail.--Srleffler (talk) 17:10, 3 May 2012 (UTC)

Damage will accumulate in proportion to the rate of metabolism. Thus the damage rate ought to be lower while sleeping when metabolism is lowered. Plus for humans we sleep indoors for the most part and at night typically, thus exposure to UV radiation and environmental pollutants ought to be lower while sleeping. SkyMachine ⁽⁺⁺⁾ 21:04, 3 May 2012 (UTC)

People are bringing up oxidative damage, but no study has ever demonstrated that the normal rate of it actually shortens your lifespan. Clearly the resulting mitochondrial mutations and increased rate of protein turnover probably aren't good for you, but that doesn't rule out that something else ruins your cells long before that extra damage matters. The best evidence for that theory is the extended lifespans of animals on super low calorie diets, but it seems plausible that's just a natural starvation response, and not an absence of damage. Antioxidants can certainly benefit various medical conditions, but there's no proof this is by lowering the rate of oxidative damage. In fact, there's no evidence that dietary antioxidants significantly reduce oxidative stress in the human body. Someguy1221 (talk) 01:39, 4 May 2012 (UTC)

Very laid back Bluebottles, how to distinguish true C. vomitoria?

Hi. This may seem like an odd question, but it's a genuine mystery for me. Whenever I've encountered flies of most descriptions during my life, they seem very edgy, like you get within 30cm of one and it takes off, not wishing to get squished. For 3 days however, I've been encountering some exceptionally laid back, almost what I'd describe as "stoned" blue bottle flies (Calliphora vomitoria). If they were anymore laid back, they'd be practically horizontal. You can approach them, pick them up and move them, put them out of a window, etc, and they make no attempt whatsoever to fly off, they don't buzz, they don't crawl away even. They just sit there. And this puzzles me. Is there any way of distinguishing if these are true C. vomitoria, or if they are a mimic species? A fly that doesn't fly away...it should be called a "walk" :^/ (Edit: One other thing, they also appear "pumped up", like they've been taking steroids or something.) MarkBurberry32|talk 19:58, 3 May 2012 (UTC)

Whenever I've come across slow insects it's because they're not warmed up enough to react quickly. Insects are cold-blooded and need a certain amount of ambient heat to function properly. I don't know where in the world you are, but certainly in the UK recently it's been cool enough to affect insects. --TammyMoet (talk) 20:11, 3 May 2012 (UTC)

These have been inside a house, TammyMoet, where the heating has been on during the day for the last few days - set at around 20°C/68°F. I can't think of any reason why they would be cold. MarkBurberry32|talk 20:23, 3 May 2012 (UTC)

I had a problem some years ago with repeated infestations of bluebottles. As it turned out they were laying eggs in a cavity wall and getting in via gaps in my Skirting board. They were very inactive which I was told was because they had recently 'matured' after pupating. If I was away from home for a few days they would be fully annoying bluebottles that couldn't be swatted without the reflexes of a ninja. Can any entomological experts confirm that young flies are lazy? 87.115.34.230 (talk) 22:39, 3 May 2012 (UTC)

Your explanation seems a very good candidate once temperature is ruled out. The other possibility is an old fly, perhaps of last autumn's generation. Blue bottle fly describes that they can hibernate as pupae or adults. SemanticMantis (talk) 23:18, 3 May 2012 (UTC)

I think they are normal blue bottles that are slow for some reason. Why would any other species mimic a housefly? You could easily confirm that it is a fly at least by checking the mouthparts and halteres, though rigorous species-level ID is quite challenging. WP:OR: I've seen similarly slow blue bottle flies and common houseflies in the fall, but never a large pulse like you describe. SemanticMantis (talk) 23:25, 3 May 2012 (UTC)

Right, so these are likely to be recently pupated bluebottles, which are in essence, slow, because they're flat out pooped from pupating or maturing? Cool :) It just seemed really odd to me to find a fly without the will to fly, so to speak. Thanks for the information guys, I appreciate the help. MarkBurberry32|talk 23:31, 3 May 2012 (UTC)

If you haven't seen them pupate, check it out: [1]. Seems very stressful indeed. The head blows up like a balloon to generate the necessary pressures! SemanticMantis (talk) 00:03, 4 May 2012 (UTC)

Bloody hell! That looks about as exhausting as you could possibly get. No wonder the poor buggers are flat out tired! Kind of reminds me of myself, as a positively fat bloke, trying to get out of a polar sleeping bag at 5am on a camping trip. Not a pretty sight :) MarkBurberry32|talk 00:51, 4 May 2012 (UTC)

Too bad the flies didn't think to add a zipper, like in your sleeping bag. StuRat (talk) 02:06, 4 May 2012 (UTC)