Humor me; can our bodies can be smaller but the same?

[rusrus]

Working on some sci-fi and exploring the theory that there is redundancy in the human body, i.e., we could function with fewer cells, then fewer amounts of elements, and therefore less matter. Could we be “fine-tuned” and exist as a smaller version of ourself?

[mith]

pygmies?

[rusrus]

yeah, but in a sci-fi type story realigning/refining an existing body and removing redundancy, therefore, making it smaller? If your eye has say xxx number of cells, are all xxx number of cells really needed? Can the eye work with yyy number of cells in theroy. Does the human body have redundancy?

[mith]

Your eye cells aren't redundant, if you had smaller eyes you'd have a smaller field of vision or see things with less resolution.

[rusrus]

I'm still not communicating my idea very well... A hawk’s eye is smaller than my eye, and may even have fewer cells, yet it is stronger. But that isn't the point really; in my research I've found that the bodies, all animals, have redundancy in the number of t cells, neurons, etc. as a way to fight brain injuries and virus. one could surmise that, in a sci-fi type work, reorganizing and reducing the dependency on this redundancy would allow for an existing body to lose cells, and size. What do you think? Leap of faith, movie wise?

[MichaelXY]

Redundancy allows for failures without a system shutdown. Like redundant harddrives, one fails the other goes online and overall system continues to operate. Removing redundancy would result in a more likely system failure. That would be a poor design overall.

[biohazard]

With modern technology, I am pretty sure that humans could function perfectly well with a much smaller frame. Basically the only thing that has to be maintained about the same size is the brain, I think, since that is about our only real asset (well, mobile hands and good vision etc, but those can be achieved with small size as well). Humans are the size they are nowadays because it was evolutionally purposeful - large enough to have some chances of survival agains bigger predators, but not any larger than necessary. However, today the things are profoundly different. You could have half the muscle mass for example and still be able to use all the tools our society offers. Bones could be thinner if we made some sort of exoskeletons to support ourselves, and the overall body size probably only had to be big enough to accommodate our brain and the function of our hands - pretty much all else is secondary. Smaller organs would be sufficient for the smaller frame, just like in smaller mammals in general.

I know that the evolutionary trend is currently a bit different - since food is plentiful in many parts of the world, there is no need to be smaller in frame, and actually women even prefer taller men in general. Furthermore, many tasks still require at least somewhat adequate muscle strength. This being said, I still believe that a smaller human (measured in cell number and/or mass) would still be perfectly viable option, if there was a reason for such. Just the brains should probably be close to the size it is now, and the hands should have the same nibmleness and ability to manipulate fine details (lesser strength is okay, even now all the heavy duty stuff is done by machines). Heck, we could do just well without legs altogether, if we just designed our society to support it. Of course, then our bodies wouldn't be the "same" anymore

Then, if by "the same" you mean an exact copy of ourselves but just with fewer cells, then I guess the limit goes somewhere around the pygmy/small child level - they should have a big enough body size to support brains that have the same or near-to capacity than an adult brain (even newborns have rather large brains )

Oh and then the other option: the number of cells would be the same, but the cell size smaller - well that would not work, for the cellular functions are so finely tuned to work in their current size frame, that, say, halving their size would result in an acute failure. I am pretty certain about this, although cannot come up with a good example right now

Finally, about redundancy - now that is a tricky topic, because what is actually redundant is probably impossible to determine. E.g. one could say that if you can live and function with only 50% of your muscle cells, half of your muscle cells were redundant. However, I am pretty certain that nobody thinks their muscles are useless, and would love to have some more. You could also remove teeth and the other eye and say they are redundant, because you can still suck a straw and be a cyclops!

I guess what is really redundant and what essential is largely determined by the environment - if you live in a tank with no threats from the outside and on an i.v. nutrition, then I guess much in us could be classified redundant. But as it stands now, when you cannot anticipate what threats and requirements the environment causes, it is better to have some spare parts, and in this case, it really is not redundant, is it?

[mith]

Wouldn't the easiest way to have smaller size be impediment of growth hormones so you would have someone who is baby sized but fully developed.

[MrMistery]

there is a disease that does that: growth hormone insufficiency(GHI)
By the way, a hawk's eye does not have less cells, it has a more of them. It also has to foveas, to be able to see moving things with an incredible accuracy. But while a hawk can see terribly well it is almost blind during nighttime(unlike a human). So number of cells is not so well connected to function, at least in this example.

[canalon]

And if I guess a smaller version of some organs could probably be still perfectly viable, some would probably not work as efficiently (I suppose that a 2x reduction of the size of your lung would probably reduce the exchange capacity by 8x) or not at all (brain for example).