C. elegans, aka Caenorhabditis elegans, is a free-living, transparent nematode of about 1 mm in length, that lives in temperate soil environments. What makes this roundworm so interesting is that the adult hermaphrodite has a total of only 302 neurons. Those 302 neurons belong to two distinct and independent nervous systems: the largest being a somatic nervous system of 282 neurons and a smaller one being a pharyngeal nervous system of just 20 neurons. This makes C. elegans a great starting ground for those studying the nervous system as all 7,000 connections, or synapses, between those neurons have been mapped.
In 2011 a project called OpenWorm launched with the goal of giving people access to their own digital worm called WormSim to study on their computers through the OpenWorm project. The project produced a complete wireframe of the C. elegans connectome, recreating all 302 neurons and 959 cells of the tiny nematode to virtually simulate the actions of the real-life worm. When simulated inputs are delivered to the nervous system, the worm sim performs a highly realistic worm-like motion.
Assuming that the behaviour of the virtual C. elegans is in-line with that of the real C. elegans, at what stage might it be reasonable to call it a living organism? The standard definition of living organisms is behavioural; 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 behaviours, combined with realistic responses to its external environment, should we consider it to be alive?
This could depend on perspective. From 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. One could argue that 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 by an outer-world.
Here is a video of the OpenWorm: C. elegans simulation:
You can check out OpenWorm at http://openworm.org