The thread was getting kind of long, so I thought I would split this off:

sraj wrote
> Also, I feel there is a basic issue with our sciences. Our world can
> be divided into two:

>The living part / the non-living part

> We excel in the sciences dealing with the non-living part. And most
> of our sciences dealing with the living part, view the living part as
> if it were non-living. There is a huge knowledge gap in our sciences!

Molecular biology seems to me like a grand success. Are you really saying we need to revert to vitalism somehow?

We have a long way to go before we can make connections from molecular biology to neurology to psychology to economics, the way we can from quantum mechanics to chemistry to molecular and cellular biology to physiology. But the problem isn't living vs non-living. We have the same problem going from planetary orbits to the formation of solar systems out of dust and gas, or from the physics of gases and water to the interaction of weather and climate.

No, not something as primitive as vitalism, but you may be aware that there
is a big debate going on whether it is possible to create the complex
lifeforms we see around us without the application of intelligence of any
kind, as Darwin thought. If there is intelligence in Nature, it would
dramatically change our view of Nature and how we should deal with the
natural world; and the best way to conduct research related to living
things.

Even without the benefit of Darwinian thought it should be obvious to anyone
(but a scientist), that living things and non-living things are differently
constituted.

Selvaraj

On 30/04/2009, Dan Wylie-Sears wrote:

Even without the benefit of Darwinian thought it should be obvious to anyone

(but a scientist), that living things and non-living things are differently

constituted.

I used to think that way,until I understood the bridge that prions and viruses make between the chemical (non-living) and living things. Consider this:

1) Under the right conditions chemicals will crystallize, making copies of themselves in solid form within a solution containing constituent pieces.
2) Prions are long-chain proteins, similar in structure to DNA/RNA but not exactly either one, which crystallize, but find the right conditions to do so most often within neural tissue. That's all they do is crystallize (replicate), they don't move under their own power, create energy or excrete waste. They count on luck to end up in neural tissue, but the fact that they get there (causing Mad Cow Disease in cattle and humans, and a weird disease that strikes only cannibals in New Guinea) is proof that it happens sometimes.

3) The simplest viruses are just RNA (sometimes DNA) within a protective coat. They replicate, but only by using the machinery of a host cell which is built for replicating using DNA or RNA. The viral DNA or RNA codes for just two things, making more of the RNA/DNA core, and making more of the protective coat. The protective coat is chemically capable of attaching to and attacking a specific type of host cell (say, a human white blood cell [HIV] or a mammalian or bird tracheal lining cell [influenza]), and inserting the virus RNA/DNA. It also counts on luck to end up in the vicinity of the host cell, it doesn't generate its own energy, move under their own power or excrete waste. The most complex viruses have a couple of layers of coat, and another part or two, all of which serve specific functions like overcoming host organism defenses or causing the host to do things like cough that will increase the virus' chances of getting to a new host. But no viruses do those "life" functions (energy production, waste excretion, independent movement), they're just prions with some accompanying structures. That is why biologists have decided that viruses are non-living, they're life-dependent chemical structures.
4) One step up are bacteria, simple plants, etc. The simplest of those are little more than viruses that have structures for energy production (mitochondria, or photosynthetic structures, or structures for making energy in other ways). They are capable of little independent movement, but they're classified as life because of energy production and waste excretion. Most reproduce on their own, but a few have to have help from other organisms to do so. It's surprising the number of one-celled organisms that require the help of viruses or other one-celled organisms, such as bacteria-virus combinations that can do things neither can do alone. This may be how bacteria and plants gained energy-producing organelles to begin with (mitochondria have their own DNA and replicate on a schedule not determined by the cell's reproduction).
The cells of multi-celled organisms are similar to bacteria (OK, they are eukaryotic, and some have specific capabilities, which bacteria don't). But basically each of us is just a community of trillions of bacteria that decided to get together and divide up the labor. If intelligence, self-awareness and a human "soul" seem qualitatively different from that, you should see some of the remarkable work neurobiologists and biopsychologists are doing to describe the biochemical processes that bring these about. It's pretty revolutionary stuff, even if demystification of that final mystery leaves us feeling somewhat less miraculous in our essence.

To me this completes the picture of increasing complexity, from chemical to "life", that leaves little doubt about the origins of life, and the essentially chemical nature of all living things.

Brad W.

___

Windows Live: Keep your life in sync.

Brad,

The information you have provided is interesting. Since I am not a biologist
I cannot fully comment on it.

On the other hand, logically speaking the scene you have unfolded is a
natural one and one that can be anticipated. Everyone knows that living
matter is formed from non-living atoms and molecules.

0......................P....................................................................100

Non-living...........................................................................Living

The point is, at some point 'P'(not at the level of ordinary
crystallisation), intelligence of a different kind will have to enter the
picture to account for the complexity of life.

Selvaraj

P.S: The genome of an Amoeba is larger than the genome of humans.

http://www.genomenewsnetwork.org/articles/02_01/Sizing_genomes.shtml

On 01/05/2009, Brad Walsh wrote: