Many species exhibit cooperative survival strategies — for example, sharing food or alerting other individuals when a predator is nearby. However, there are almost always freeloaders in the population who will take advantage of cooperators. This can be seen even among microbes such as yeast, where “cheaters” consume food produced by their neighbors without contributing any of their own.
Among yeast, cooperative members of the population actually have a better chance of survival than cheaters when a competing species is introduced into an environment.
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