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Frankenstein's simulated worm is alive?


January 3, 2014

A view of the OpenWorm simulated nematode while swimming (Photo: OpenWorm)

A view of the OpenWorm simulated nematode while swimming (Photo: OpenWorm)

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The OpenWorm project is aimed at creating the first artificial lifeform – a bottom-up computer model of a millimeter-sized nemotode, one of the simplest known multicellular organisms. In an important step forward, OpenWorm researchers have completed the simulation of the nematode's 302 neurons and 95 muscle cells and their worm is wriggling around in fine form.

The C. elegans nemotode is one of the simplest multicellular organisms known. Its hermaphroditic form has only 959 cells, of which 302 are neurons. Despite this simplicity, the nematode is equal to the usual challenges of living, such as feeding, reproducing, and avoiding being eaten.

An organ-level view of a C. elegans nematode (Photo: OpenWorm)

To model the complex behavior of this organism, the OpenWorm collaboration, begun in May 2013, is developing a bottom-up description. This involves making models of the individual C. elegans cells and their interactions, based on their observed functionality in the real-world nematodes. Their hope is that realistic behavior will emerge if the individual cells act on each other as they do in the real organism. artificial animal

A coarse schematic of the cellular interactions leading to behavior of a C. elegans nemato...

At present, input-output models for the individual cells are being used. For example, the model of a muscle cell says "I am such a size and shape when relaxed, and the mechanical properties of my membrane and innards are such and such. I'm connected to the following list of cells through contact with certain portions of my cell membranes. Six neurons make contact with my structure, which produce the following list of behaviors when stimulated. My passive and active responses to cells surrounding me make up my model."

This approach is intended to see if both the homeostatic and dynamic behaviors of the nematode can be modeled without requiring a complete description of the underlying chemical reactions.

The complete connectome, or neural cell connections, for a C. elegans nematode (Photo: Ope...

The simulated nematode is being built of code packages corresponding to the various types of cells and interconnections found in a real C. elegans. Fortunately, we know a lot about these nematodes. The complete cellular structure is known, as well as rather comprehensive information concerning the behavior of a real C. elegans in reaction to its environment. Included in our knowledge is the complete connectome, a comprehensive map of neural connections (synapses) in the worm's nervous system.

At present, the model has grown to include the 302 neurons of the nervous system and the complete set of 95 muscle cells. When simulated inputs are delivered to the nervous system, the simulated nematode performs a highly realistic swimming motion (see video below).

Assuming that the behavior of the simulated C. elegans continues to agree with the real animal, at what stage might it be reasonable to call it a (very simple) living organism? The usual definition of living organisms is behavioral; they extract usable energy from their environment, maintain homeostasis, possess a capacity to grow, respond to stimuli, reproduce and, through natural selection, adapt to their environment in successive generations. If the simulation exhibits these behaviors, combined with realistic responses to its external environment, should we consider it to be alive?

One might argue for an altered version of the Turing test. In the Turing test, a computer is considered sentient and sapient if it can simulate the responses of a conscious sentient being so that well prepared and suspicious auditors cannot tell it isn't a person. The modified Turing test for life might say that a simulated organism is alive if a skeptical biologist cannot, after thorough study of the simulation, identify a behavior (or lack thereof) that argues against the organism being alive. As in the traditional Turing test, behavior that seems appropriate for a living being is considered strong evidence that the organism is, in fact, alive.

On the other hand, this criterion feels too easy to meet, suggesting that I at least have a number of basic prejudices about what life is. This, of course, was the purpose of the Turing test, to eliminate such prejudices by filtering the interaction through a machine (originally a teletype). So is something alive if it behaves alive? If not, why? If we made a nematode by putting a batch of artificial, but physical, cells together in the right order, would it be alive?

As humanity is traveling along various paths that seems on the verge of creating "artificial life" from several directions, it is probably time that we figure out how to differentiate the living from the nonliving. Structure? Behavior? DNA? Local reduction of entropy? Fortunately, this is a question whose answer is above my pay grade.

The following video shows the simulated worm strutting its stuff.

Source: OpenWorm

About the Author
Brian Dodson From an early age Brian wanted to become a scientist. He did, earning a Ph.D. in physics and embarking on an R&D career which has recently broken the 40th anniversary. What he didn't expect was that along the way he would become a patent agent, a rocket scientist, a gourmet cook, a biotech entrepreneur, an opera tenor and a science writer.   All articles by Brian Dodson

Is it alive? This depends on perspective.

In the outer-world perspective, the worm is obviously a non-living simulation that mimics life inside a computer.

In the inner-world perspective of the simulation, the worm is absolutely alive as it is obeying the laws of physics as presented by the simulation.

In comparison to the world in which we exist, there is nothing that can confirm for us that we too are not living in a world that is a simulation produced from some outer-world. More and more, physicists are declaring that the ultimate foundation of our world is information. Further, we haven't a clue as to what "energy" is composed of. As far as we know, energy might simply be some prescribed value granted from some outside source. Until we can state definitively what energy is, we can't rule out that we too are simulated. Regardless, simulated or not, we certainly feel that we exist and are real. By the same measure, so too would any creature that we validly create in our computer simulations.

Simulations like this are another step toward computer games that compute things from the cellular level and then eventually the subatomic particle level. Games/simulations fifty to one hundred years hence will be able to either be programmed at a particular state or programmed to evolve. Some will simulate our world while others will have completely different physics. By the reasoning expressed above, any cognizant intelligences created within them will feel that they are alive. Ongoing synthetic brain research will converge with world simulation technology, so virtual worlds with intelligent beings are certain to come, again whether fabricated or evolved.

6th January, 2014 @ 12:13 pm PST

The reason we care about the semantics is, presumably, because of associated sociological implications. Living things have natural rights so it's important to decide whether a simulated being is living or not. I agree with this but, as exciting as this development is, and it is exciting, I think the OpenWorm project is likely to muddle that question, rather than provide a catalyst for clarity.

The reason? Because even among "truly living" creatures, we naturally divide them into varying levels of "aliveness." Many people are content to let biologists call the neurotode worm alive, but will balk at giving that worm the same consideration they would a puppy.

The question of whether simulated creatures are alive won't really be put to us until we manage to simulate something to which we would, in the real world, universally ascribe rights and protections.

M. Scott Veach
6th January, 2014 @ 03:45 pm PST
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