MoonlitSunshine

That's.... kinda the point. You understand the concept of Natural Selection? The scientists wanted to show that a usually uni-cellular organism could be forced to evolve into a predominantly multi-cellular organism, provided that it was "optimal" to do so. In order to show this, they "rigged" the experiment so that the multi-cellular version should thrive and dominate. This is exactly what happened.

The "removing" of the uni-cellular free floating yeast at intervals was used to emulate "dying out" in nature - think of it like a plant evolving in two strains, one which kills what eats it and the other which doesn't - the predators would learn over time to eat only the non-lethal one and thus the non-lethal one would eventually die out (or at least shrink vastly in population) over time, provided it didn't have other more profitable mutations like a faster propagation rate.

"Evolution" isn't just the random mutation of organisms. Mutation happens as a matter of course, everything mutates, Evolution is the combination of Mutation and Natural Selection, where the Mutations which survive more successfully naturally grow to form the dominant part of the base population.

To relate that to this experiment, the environment was set up so that multi-cellular life had a greater survival chance. Their method of doing so might have been rather crude, but it was as effective and essentially equivalent to the free-floaters "dying out" due to other more natural reasons.

Or at least, that's how I've come to understand it.

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