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I wonder why most of us find senior people lovely and charming. Is it because to love grandpa and granny is vital to our survival as a species, in the same way as we love babies? If so, it would mean that we are either aging slower with time, or being selected somehow to love senior people despite their physical appearance, while they are aging at the same rate but living longer.

Update

Let's say every common characteristic among individuals of the same specie is product of evolution. Many caracteristics are passed by the individuals to their offspring, but only those that were advantageous in some way or another allowed the offsring to survive and pass that caracteristic to their decendants in turn. Our love for babies and elders is one of those caracteristics that we as indivudials of a species have in common. That make us to want our elders to be with us as much time as posible, just becouse our affinity with them. This love for the elder have to be an advantaje that worthed to be selected by the evolutionary process, and this caracteristic is reflected in the tendency of the life expectancy to increase generation after generation. One could say, that those elders that age slower would be more likely to benefit from the love of their offspring, than those that age faster. On the other hand, to age slower may not make a difference at all, just because we love our elders despicte their physical appearance. I'm considering the cultural and technological advantages that allow our elders to live longer to be a product of evolution too.

So my question is wheter we are evolving to age slower, or to live longer aging at the same rate?

As a side note, we are becoming more like what they call a super-organism, as most of os can only benefit of a longer life spam by living in society. Just like an anthill or a beehive. If that is true, we are not evolving to age slower.

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Your premise is debatable and your argument is, frankly, nonsensical. Why does feeling affection for our elders imply that we are "aging slower with time" (whatever that means)? Voting to close. –  terdon Jun 2 '13 at 2:58
    
@terdon We feel affection for our elders, as a matter of fact, but that behavior has to be shaped somehow by evolution. Also life expectancy is increasing generation after generation, and we still feel such affection. The implication is obvious to me, we are evolving to love people that live longer. What I'm asking is whether we are being selected because we love people that age slower, or because we love elders despite their physical appearance. –  rraallvv Jun 2 '13 at 3:28
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Not all behaviors have to be shaped by evolution. We do plenty of things that are counter-productive to our continued existence as a species and/or as individuals, as a moment's reflection will tell you (nuclear proliferation, global warming, drinking and driving, etc.). Please read this question and its answers to better understand the terms "evolution" and "evolve." –  MattDMo Jun 2 '13 at 4:20
    
@MattDMo I would say every behavior that is common among individuals of a species has to be due to natural selection, because it's being selected among many other behaviors that weren't. In the case of the love for the elder, it would mean that people that didn't experience such feelings in the same way was not favored by natural selection. –  rraallvv Jun 2 '13 at 12:55
    
i wish we could be more tolerant of questions like this. –  shigeta Jun 4 '13 at 21:03
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The question has a more or less official scientific name - the grandmother effect (or hypothesis). In the rational world of evolutionary biology, children love their parents for the same sort of reason - the parents give them resources to gather their strength and develop as adults so they can have their own children with the most advantage that they possibly can.

Humans are off the charts in the amount of resources we invest in our children - our lives are 1/4 to 1/3 over before we sometimes leave our parents household (in some societies of course they never leave the house, but step into an extended family). This may be one of the reasons we are so successful as a species - we live in practically every place we possibly could and have no danger of competition from any other living thing excepting ourselves.

The grandmother effect is essentially the idea that if women, who are more attached to the offspring in more cases than fathers, continue to live and help support the grandchildren and make them more successful, then this will allow post menopausal women to have a longer lifespan (which they do).

The evolutionary biologist Sara Hrdy, emeritus UC Davis, has written quite a bit about the nuances of the evolution of the role of motherhood - reading some of her articles or books might give you a deeper sense of how profoundly filial love has shaped human beings.

--- more answer this stuff may or may not be worth reading depending on how broadly you want to understand this question...

Its important to say that many of the expansions of human average human lifespan have not been genetic. Its commonly cited that sewer systems, clean water, antibiotics and plentiful food are the three most important factors in human lifespan - and before modern developed world nations, the average lifespan of human beings was somewhere in the 30s. And there are significant lifespan differences in regions where these factors and others (education of women, access to prenatal and early care etc) are available.

Studies continue to be published that examine environmental and lifestyle factors compared to genetics and it seems that environment and lifestyle can make an astounding difference.

But genetics undoubtedly has a role to play here too. There are probably some individual humans and animals which have evolved to live longer. This has been found to be genetically related in some humans by demographics and family lines.

Still there are genetic factors that are being identified. I think its a common misconception that evolution changes the entire species, but its not really true. There are some who have that tendency and others who do not - at times there will be more of say shorter lived people and other times longer lived individuals will be more common. It depends upon whether the living conditions of the population really favor one tendency over another. Usually shorter lived individuals can assume to have other advantages, say the ability to store energy more efficiently.

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One could say that cultural and technological advantages are part of being human, if so they are being shaped by evolution too. In the other hand that could imply that our species is becoming more like a superorganism, like an ant-hill, where one organism can't have the benefit of a longer live span by itself, but only if one live in a colony. –  rraallvv Jun 2 '13 at 12:51
    
that's true, though in terms of biology and evolution that's language that needs careful discussion - superorganism sounds a little like group selection and not everyone is into that idea ;) –  shigeta Jun 2 '13 at 14:50
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