Biological Negotiation
There is a theory that there is a negotiation between species, the extremes are parasites and beneficial life forms. There are parasitic lifeforms that start as a disease with a high fatality and eventually "learn" to not kill the host before finding another host and eventually becoming a minor ailment or even adapt to the host in a way that is beneficial to the host and the parasite.
We have E. Coli in our intestines, a beneficial group that helps digest food for us. There are other E.Coli that contaminate food in outbreaks of food poisoning.
The best example of biological negotiation are flowering plants and pollinators that co-evolve together. Bees thrive through gathering nectar from flowers, plants thrive because the bees pollinate the plants.
