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In this information, there is a discussion about the interaction between killer yeast, sensitive yeast, and resistant yeast. Killer yeast dominate sensitive yeast, but sensitive yeast can evolve resistance and become unaffected by killer toxins. However, sensitive yeast can still win against resistant yeast. The reasons for this are debated, but one theory is that resistant cells lose their advantage and become sensitive again. Another theory is that resistance consumes energy, making it harder for resistant cells to grow. Sensitive yeast may appear weak, but they have hidden advantages that allow them to coexist with other yeast cells. The interaction between these different types of yeast is a cycle with no clear winners. Now we call the victims of the killer yeast, sensitive yeast, because as you might have guessed, they're sensitive to the toxin. But there's a third player in this evolutionary chess game, and this arises as resistance to the killer toxin can evolve spontaneously. Resistant yeast can actually counteract killer toxins and remain unaffected. When they all interact with each other, we end up with a game of rock-paper-scissors. Let's break it down. Killer cells first dominate the landscape against sensitive cells, as they possess the killer factor crucial to taking over. However, as time passes, sensitive cells can evolve resistance, and resistant cells possess the antidote to killer toxins, so they remain unaffected. This makes it so that the killer toxin is quite worthless, and in fact, costly. And to complete the cycle, sensitive yeast win the game against resistant yeast. Why this happens is a hot topic of debate for yeast scientists everywhere, but they have two theories. When resistant cells take over, killer numbers dwindle, but so does the advantage of resistance. What point is there to be resistant if there's nothing to be resistant to? Cells will start to lose their resistance, evolving to become sensitive cells again. That may be why sensitive yeast dominate resistant yeast. The second theory is that resistance is energy-consuming. A yeast cell may waste a lot of effort maintaining its own resistance to killers, so it doesn't have as much energy left to grow. A sensitive cell can just devote all of its energy to gaining resources and growing. Put these two theories together, and you now have a solid idea of how they interact. Sensitive yeast may look weak, but they have a hidden advantage which allows them to coexist with others. The resulting cycle shows us that there are no winners, and whoever comes out on top is dependent on the circular interactions between neighbouring yeast cells.