Plasma blobs hint at new form of life

New Scientist ^ | 09/17/03 | David Cohen

[bedolido]

Physicists have created blobs of gaseous plasma that can grow, replicate and communicate - fulfilling most of the traditional requirements for biological cells. Without inherited material they cannot be described as alive, but the researchers believe these curious spheres may offer a radical new explanation for how life began.

Most biologists think living cells arose out of a complex and lengthy evolution of chemicals that took millions of years, beginning with simple molecules through amino acids, primitive proteins and finally forming an organised structure. But if Mircea Sanduloviciu and his colleagues at Cuza University in Romania are right, the theory may have to be completely revised. They say cell-like self-organisation can occur in a few microseconds.

The researchers studied environmental conditions similar to those that existed on the Earth before life began, when the planet was enveloped in electric storms that caused ionised gases called plasmas to form in the atmosphere.

They inserted two electrodes into a chamber containing a low-temperature plasma of argon - a gas in which some of the atoms have been split into electrons and charged ions. They applied a high voltage to the electrodes, producing an arc of energy that flew across the gap between them, like a miniature lightning strike.

Sanduloviciu says this electric spark caused a high concentration of ions and electrons to accumulate at the positively charged electrode, which spontaneously formed spheres (Chaos, Solitons & Fractals, vol 18, p 335). Each sphere had a boundary made up of two layers - an outer layer of negatively charged electrons and an inner layer of positively charged ions.

Trapped inside the boundary was an inner nucleus of gas atoms. The amount of energy in the initial spark governed their size and lifespan. Sanduloviciu grew spheres from a few micrometres up to three centimetres in diameter.

Split in two

A distinct boundary layer that confines and separates an object from its environment is one of the four main criteria generally used to define living cells. Sanduloviciu decided to find out if his cells met the other criteria: the ability to replicate, to communicate information, and to metabolise and grow.

He found that the spheres could replicate by splitting into two. Under the right conditions they also got bigger, taking up neutral argon atoms and splitting them into ions and electrons to replenish their boundary layers.

Finally, they could communicate information by emitting electromagnetic energy, making the atoms within other spheres vibrate at a particular frequency. The spheres are not the only self-organising systems to meet all of these requirements. But they are the first gaseous "cells".

Sanduloviciu even thinks they could have been the first cells on Earth, arising within electric storms. "The emergence of such spheres seems likely to be a prerequisite for biochemical evolution," he says.

Temperature trouble

That view is "stretching the realms of possibility," says Gregoire Nicolis, a physical chemist at the University of Brussels. In particular, he doubts that biomolecules such as DNA could emerge at the temperatures at which the plasma balls exist.

However, Sanduloviciu insists that although the spheres require high temperature to form, they can survive at lower temperatures. "That would be the sort of environment in which normal biochemical interactions occur."

But perhaps the most intriguing implications of Sanduloviciu's work are for life on other planets. "The cell-like spheres we describe could be at the origin of other forms of life we have not yet considered," he says. Which means our search for extraterrestrial life may need a drastic re-think. There could be life out there, but not as we know it.

David Cohen

[Dataman]

How do they know this?

In this brave new world, wild guesses evolve into facts whenever a postmodernist declares them so.

[aruanan]

Why?

Because philosophical predispositions control where, how, and why one looks for something. One may have the means by which something could be discovered and yet never discover it because one's philosophical predispositions have already ruled out the possibility.

[ChadGore]

I, for one, welcome our new Plasma Blob overlords.

[RightWhale]

one looks for something

That's important. One already has an idea of what to look for, an idea of what it is or at least the domain it belongs to so that one may formulate the proper question.

[RightWhale]

wild guesses evolve into facts

Then there come so many facts that science organizes them into categories so they may be dealt with in groups.

[Junior]

Self-organizing complexity bump.

[Junior]

Ah, but you miss the point. Here we have spontaneously-arising self-organizing complex systems.

[Arthalion]

In this brave new world, wild guesses evolve into facts whenever a postmodernist declares them so.

1) We know that there used to be far more lightning in the atmosphere because we can SEE the fused rocks and stones in the exposed surface rock layers from that time period. Most of the earths topsoil has been created over billions of years by dying plant life (both through decomposition and the breakup of surface rocks). In the time period before life was created here, most of the Earth's surface was bare rock...with "soil" only existing in river basins and along the coasts. Since stone lasts a long time, and the telltale lightning fusing on impact points lasts just as long, we are able to gain a basic understanding of the frequency of ligtning strikes in primordial times. Lightning used to be a LOT more common than it is today (probably because primordial Earth had no continents or mountain ranges to block weather systems, which allowed monsoonal storms from the equator to travel nearly to the poles).

2) We know the chemical makeup of the atmosphere at that time by examining the same rocks. We know that certain rock properties can only be created when certain gasses are present or absent. While it's not an exact science, it can, for example, tell us that there was very little oxygen on the early Earth, and that other gasses (like CO2 and Argon) used to be in much greater abundance.

[Junior]

The definition of life does become fuzzy the further down you go. For instance, are self-replicating molecules alive?

[Ahban]

C'mon. You don't seriously believe this had any role in biogenisis?

[onedoug]

Some geochemistry: ratios of isotopes and oxidation in Precambrian limestones, for example, and their rates of change relative to later, similarly placed sedimants. Extrapolation. Guesses, though not necessarily uneducated ones.

[Junior]

Maybe not directly, but it points to spontaneous self-organization being a fact of nature. That implication alone is extremely important.

[BlazingArizona]

If these guys try to sell you property in Florida...

...Conditions on it would probably be ideal for breeding those things. You could grow your own lawyers whenever needed.

[Arthalion]

Because philosophical predispositions control where, how, and why one looks for something. One may have the means by which something could be discovered and yet never discover it because one's philosophical predispositions have already ruled out the possibility.

Exactly. A real world example: I couldn't find my wedding ring this morning. I didn't look on my dresser because I knew that I NEVER put it there, so it would be impossible for it to be located there. I had a predisposition to believing that the ring couldn't be located there which was supported by prior research and historical patterns. I searched my clothes, bathrooms, and car for nearly 20 minutes before my wife finally found it...on my dresser.

Science is the same way. You can't walk into an experiment with a solid understanding of what you're looking for, because that type of science only yields obvious, predictable results. Some of the greatest scientific discoveries in mankinds history started with the thought, "I wonder what would happen if...". Most of the time, random experimentation is a waste of time. Occasionally it gives us things like penicillin. Directed science has a place, but it's certainly no more important that pure research and experimentation.

[Diogenesis]

This is nonsense. Otherwise, rock candy is a new species.

Rock salt will be defended by the ACLU.

And expect feldspar to demand its civil rights.

MORAL: Take nothing for granite.

[Junior]

Why do you take off your wedding ring? Mine's fused to my hand over the years...

[Arthalion]

Why do you take off your wedding ring? Mine's fused to my hand over the years...

I take mine off when I'm sleeping, working on the car or the house, washing or showering...that sort of thing. You never take your ring off?

[11B3]

It would only violate the 2nd Law if it were capable of energy output greater than that which it was composed of. Positive energy output like that would indeed seem to indicate a living process.

[PatrickHenry]

Belated PING. [This ping list is for the evolution side of evolution threads, and sometimes for other science topics. FReepmail me to be added or dropped.]