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Unintelligent design

Dave Rogers

Bandaged ice that stampedes inexpensively through
Dave Rogers
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A comment in the Intelligent Design thread has started me thinking.

PartSkeptic said:
Some people think that humans are very badly designed. But they do not have a better one.
Click to expand...

It seems to me that there are many instances where the design of the human body is obviously - not to put too fine a point on it - downright wrong. There are of course different trade-offs in any design, so it's not really a valid criticism to point out that, say, humans are much slower than cheetahs, because we're optimised for a different set of parameters. However, there are obvious instances where either the design of the body is clearly not thought out, or where a superior design element exists in nature. The classic example of the latter is the difference between human and cephalopod eyes; simply routing the nerve connections round the back of the retina in the latter is not only obviously superior but also exists in reality, so one can't realistically come up with an excuse for the blind spot in humans, where the optic nerve is routed through the retina, in claiming intelligent design.

An example of the former, it seems to me, may be the urinary tract. There are two completely separate excretory systems in mammals; the alimentary canal extracts nutrition and water from food and drink, and the kidneys take up some of the water ingested to remove waste products from the blood. The urinary system wastes water; not a problem for an organism living in water, but quite an inconvenience for one living on land, because we're reliant on sufficient water to keep hydrated and to maintain kidney function. If the urinary tract were routed into the alimentary canal, which is already set up to separate waste from water, wouldn't it be a more efficient design, and quite a realisable one?

A couple of questions, then:

From someone whose knowledge of biology is better than mine (I'm a physicist so I admit I don't value understand biologists biology ;)), does that sound like a reasonable criticism?

And:

What other good examples are there of obviously poor design (rather than questionable trade-off choices) in biology?

Dave
 
The classic for me is the laryngial nerve, which travels from the brain to the larynx (just a few inches apart)........via the aorta!! Yep, it goes down into the chest, around the body's most important blood vessel, then back up into the throat, a journey of a couple of feet or more when 4 or 6 inches would have done it the direct way. That's stupid enough in humans, but get this. It does exactly the same thing in giraffes!! Instead of being 6 inches long, it can be 12 feet long.

The bloody prostate is a damned silly idea, too, wrapped around the urethra.
 
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And PS's "they don't have a better one" actually says nothing germane to the matter. PS can consult with any doctor to learn the numerous aspects of the human body which might be "better." But what we have is what we got via the process that brought us here.
 
We have found a number of genes that significantly reduce the chances of getting certain diseases and types of cancer.
Yet only very few people have them when it would be trivial, from the POV of a creator, to give them to all humans.
Luckily, science might soon pick up the slag.
 
The slag usually runs for elective office. (:)) You mean slack, and that would be a great boon to mankind.
 
Testicles.

Dangling in harms way outside the body. Vulnerable to attack, barbed wire fences, and thorn bushes. Elephants have in-board bollocks (they're up around their kidneys, giving them a 6 or 7 foot seminal path..........no wonder they make so much noise when they ejaculate!!), so I really can't see why a perfect designer couldn't have found a more sheltered location for the family jewels.
 
There are a number of obvious 'design' flaws, most of which have been mentioned in that (and many other threads)

For me two of the more glaring examples are the fact that we (and all eukaryotes) waste energy into making two different sets of ribosomes (one for the cell, one for mitochondria) and don't have the genetic material to make a mitrochondria de novo if they get lost during cell division.

There is also the fact that human cells are repressed from behaving as single celled organisms with a series of complex interactions, a mistake in one of which will lead to cancer, which the immune system cannot recognize in 99.99% of the cases.
 
MikeG said:
Testicles.

Dangling in harms way outside the body. Vulnerable to attack, barbed wire fences, and thorn bushes. Elephants have in-board bollocks (they're up around their kidneys, giving them a 6 or 7 foot seminal path..........no wonder they make so much noise when they ejaculate!!), so I really can't see why a perfect designer couldn't have found a more sheltered location for the family jewels.
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Thermal regulation.

There's always the old sewage plant next to the playground one.
 
MikeG said:
That's what we're always told, but elephants manage OK.
Click to expand...


Yeah, the testicles themselves aren't the bad design; they're a compensation for a more basic bad design, of having a core body temperature several degrees higher than the optimum temperature for our own spermatogenesis.
 
Not so intelligent design.

There is an excellent book by A. Hafer titled "The Not So Intelligent Designer" published in 2015 by Cascade Books in Eugene, Oregon that goes over the things that a truly intelligent designer wouldn't have gotten wrong. One that I'd never thought of was that humans don't have the final step in the biochemical pathway used to synthesize Vitamin C. We've got everything up until that last step. Sort of silly to leave out that last bit!
 
We can choke to death, because for some reason our air tube joins up with our food tube for a bit before separating again.
 
Dave Rogers said:
If the urinary tract were routed into the alimentary canal, which is already set up to separate waste from water, wouldn't it be a more efficient design, and quite a realisable one?
Click to expand...


It doesn't detract much from your overall point, but I don't think that arrangement would work.

As far as I can recall from long-ago biology classes, water absorption in the GI tract is mostly passive diffusion of the water into the bloodstream.

Elimination of wastes in the kidneys is also largely passive diffusion out of the bloodstream into the nephrons. The hard-work part of what the kidneys do is the subsequent active re-absorbtion of most of the useful nutrients, salts, and water.

Re-routing the urinary tract into the alimentary canal would be the equivalent of attempting to conserve water by drinking ones own urine. Which people in extreme situations have been known to resort to, but the results are generally poor.

Other species have different ways of breaking down nitrogenous waste products into less toxic molecules (e.g. uric acid instead of urea), making kidney function more efficient in terms of wasted water. Birds, for instance, don't urinate.
 
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Dave Rogers said:
*snip*
An example of the former, it seems to me, may be the urinary tract. There are two completely separate excretory systems in mammals; the alimentary canal extracts nutrition and water from food and drink, and the kidneys take up some of the water ingested to remove waste products from the blood. The urinary system wastes water; not a problem for an organism living in water, but quite an inconvenience for one living on land, because we're reliant on sufficient water to keep hydrated and to maintain kidney function. If the urinary tract were routed into the alimentary canal, which is already set up to separate waste from water, wouldn't it be a more efficient design, and quite a realisable one?
*snip*
Click to expand...

Well, that is the system birds and reptiles have. It works fine if somewhat messily. The separated system has various advantages, one of which is independent discharge.

Hans
 
MikeG said:
Testicles.

Dangling in harms way outside the body. Vulnerable to attack, barbed wire fences, and thorn bushes. Elephants have in-board bollocks (they're up around their kidneys, giving them a 6 or 7 foot seminal path..........no wonder they make so much noise when they ejaculate!!), so I really can't see why a perfect designer couldn't have found a more sheltered location for the family jewels.
Click to expand...

Well, it is a question of temperature. The testicles don't work well when hot, but that could probably have been remedied (since it works for the elephants).

Hans
 
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