Design of the human body

[Winston001]

Recovering from a spinal injury I got to thinking..........

I've wondered for some time about the efficiency of creature's bodies - including homo sapiens. Almost every animal has a head situated upon a neck. Within that head resides the brain which is the critical organ for survival. Mammals, insects, reptiles, birds. Fish are the exception, and even then the brain is at one end. Not sure about amoeba and bacteria.

Now, the brain is so important that I can't see why evolution would allow it to sit in such an exposed position. Why not position the brain in, say, the chest? By all means have a head with eyes and ears, but for goodness sake protect the machine which is critical to survival. And the brain would then be closer to the spine for running the central nervous system.

There's another thing - why expose the spine on one side of the body? Yes its needed for skeletal purposes but why not a central spine with two rib cages?

After all, our bodies are complex constructions anyway and these variations wouldn't be any more strange than what we already have.

So I'm interested in your ideas.

[Thaeos]

Well ... because there is no design. No thought has gone into it whatsoever. It is not an intelligent process with considerations for what we think would be better or would make humans stronger/more resistant to damage.

[Slyer]

Indeed. Evolution by definition isn't planned, the species tends towards improvement slowly over a long period of time.
We have so many back problems because our spines have evolved from fish spines. The spines have adapted a lot for upright walking but you can only ever adapt so much. You could never have a complete redesign without an designer.
Check this out:

[SS90]

Yes, and I have to admit, the idea of shagging a bird with a chest in the front and a chest in the back sickens me.

I am 100% happy with the way our bodies are designed

Particularly the Woman's bodies.

Particularly Jessica Beale's body.

Thank you evolution!

[Brian d marge]

Recovering from a spinal injury I got to thinking..........

I've wondered for some time about the efficiency of creature's bodies - including homo sapiens. Almost every animal has a head situated upon a neck. Within that head resides the brain which is the critical organ for survival. Mammals, insects, reptiles, birds. Fish are the exception, and even then the brain is at one end. Not sure about amoeba and bacteria.

Now, the brain is so important that I can't see why evolution would allow it to sit in such an exposed position. Why not position the brain in, say, the chest? By all means have a head with eyes and ears, but for goodness sake protect the machine which is critical to survival. And the brain would then be closer to the spine for running the central nervous system.

There's another thing - why expose the spine on one side of the body? Yes its needed for skeletal purposes but why not a central spine with two rib cages?

After all, our bodies are complex constructions anyway and these variations wouldn't be any more strange than what we already have.

So I'm interested in your ideas.

i am reporting you to ACC ,n you can think and move at least one muscle therefore you are fit for work
so get to it

Stephen

I am not standing by while a perfectly good human being throws away the opportunity to work

[SPORK]

those in the know, will know

[rainman]

So I'm interested in your ideas.

Good questions. My NSWAGs would be that the spine evolved on one side because the legs were on the other (when we were running about on all fours), and the brain evolved close to the primary sense organs (eyes, ears, mouth).

But that could be complete crap. Why don't you ask the dude from The Straight Dope? (Is he still there?)

[McJim]

I hope you're not hinting at creationism Winston. It's all very well defending an indefensible position for arguments sake but thet's going too far.

Most mammals were not designed to travel faster than 70kph...shit most of 'em aren't even designed to go faster then 30kph!

At these speeds very very few (in overall %age terms) suffer from spinal injuries.

The best place for eyes is at the topmost area of the creature. The best attribute for the part holding the eyes is to be prehensile to some extent.
The most efficient route for an optic nerve is a short direct connection hence requiring the part of the body used for receiving optical nerve transmissions to be pretty close to the eyes.

Any other design simply wouldn't make it through the first 50 million years bro'

QED

[Cheshire Cat]

I am loling at the moment, this is very bizaaarrr!!!

[FJRider]

Yes, and I have to admit, the idea of shagging a bird with a chest in the front and a chest in the back sickens me.

I am 100% happy with the way our bodies are designed

Particularly the Woman's bodies.

Particularly Jessica Beale's body.

Thank you evolution!

I TOTALLY agree .... but I do feel they need more study ....

[Thaeos]

I TOTALLY agree .... but I do feel they need more study ....

I'd like to help with that study...

[McJim]

I TOTALLY agree .... but I do feel they need more study ....

I'd like to help with that study...

The idea of you both studying one another is not something I'd like to have to take notes on. And I'm not even homophobic.

Best of luck lads and I hope you do enjoy yourselves...

[FJRider]

I'd like to help with that study...

Sorry ... this study I must do on my own. I may however require (for study purposes only mind) the services of suitably (endowed/qualified) females to study. Those females wishing further study ... PM me (with photo).... Discretion assured ....

[Pixie]

Recovering from a spinal injury I got to thinking..........

I've wondered for some time about the efficiency of creature's bodies - including homo sapiens. Almost every animal has a head situated upon a neck. Within that head resides the brain which is the critical organ for survival. Mammals, insects, reptiles, birds. Fish are the exception, and even then the brain is at one end. Not sure about amoeba and bacteria.

Now, the brain is so important that I can't see why evolution would allow it to sit in such an exposed position. Why not position the brain in, say, the chest? By all means have a head with eyes and ears, but for goodness sake protect the machine which is critical to survival. And the brain would then be closer to the spine for running the central nervous system.

There's another thing - why expose the spine on one side of the body? Yes its needed for skeletal purposes but why not a central spine with two rib cages?

After all, our bodies are complex constructions anyway and these variations wouldn't be any more strange than what we already have.

So I'm interested in your ideas.

The brain in all animals is adequately protected for it's normal natural environment.e.g. the human skull protects the brain well for accidents like tripping and doing a faceplant while running.It doesn't do so good when you accelerate the human to 120 km/h and run it into a tree.

[erik]

There's another thing - why expose the spine on one side of the body? Yes its needed for skeletal purposes but why not a central spine with two rib cages?

Bearing in mind I haven't studied much evolution or biology...

In quadrupeds, the torso is like a cantilever beam, the top side in compression, the bottom in tension. Muscles only work in tension. Bones (the spine) deal with the compression. So mammals evolved with the spine at the top to take the compressive loads, with the organs hanging underneath, and the stomach muscles looking after the tensile loads.

Humans started from there and evolved to where we're at now.

What I find kind of surprising is how central the spine actually is, if you look at cross-sectional images of the abdomen/lower back region in particular:
http://www.meddean.luc.edu/lumen/Med...c/abd/1680.htm

http://www.madsci.org/~lynn/VH/transverse.html

I wasn't able to find cross sections of four legged creatures, it would be interesting to see how the spine position compares. Presumably it is in a more dorsal position in quadrupeds vs humans.