Nature’s intelligence shines clearly in her choice to protect, within various organisms, what is most valuable.
Consider, for instance, the human body: Its brain is nestled within a sturdy skull, and the spinal cord within the fluid stronghold of the spinal column. The ribcage forms a protective barrier around other vital organs—heart, lungs, kidneys and spleen. And this is wise!
Now, perhaps every once in a while, as an expression of her infinite creative potential, or just for fun, Nature might create a human being sans the protective garb: a human without a skull or spinal column (the brain and spinal cord fully naked to the elements); and without a ribcage to hold and firmly organize the other vital organs.
That would be a sight to see! Though you’d need to catch a glance quite quickly, while you had the chance, since the lifespan of such a creature would almost certainly be brief, in the extreme.
And Nature would likely realize that her original design was, after all, the best one, at least for now …