How does cooperation evolve?

If you find this animation helpful, consider supporting our work at http://statedclearly.com/contribute/ Lichen is a combination of algae and fungus (and in many cases, a third species of yeast) living together. This relationship allows the intertwined organisms to survive in locations they could never live on their own. If evolution is all about "survival of the fittest", how does cooperation evolve? Living things form cooperative relationships all the time. Research done by applying mathematics to biology is helping us understand the evolution of cooperation. Cooperation has caused some of the major evolutionary steps in the history of life, including the step from single celled creatures to multi-cellular plants and animals. Scientists used mathematical models to find scenarios in which natural selection will actually favor cooperation. Sources: Many species of fungus feed on lichen: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4047527/ Kin selection combined with budding can give rise to cooperation: Demography, altruism, and the benefits of budding: http://onlinelibrary.wiley.com/doi/10.1111/j.1420-9101.2006.01104.x/abstract Mathematical Models of cooperation: Kin Selection: http://www.sciencedirect.com/science/article/pii/0022519364900384 Direct Reciprocation: http://www.ncbi.nlm.nih.gov/pubmed/8316296/ Indirect Reciprocation: http://www.ncbi.nlm.nih.gov/pubmed/10797005/ Network Reciprocation: http://www.nature.com/nature/journal/v433/n7023/full/nature03204.html Five Rules for the Evolution of Cooperation: http://www.ncbi.nlm.nih.gov/pubmed/17158317 New Discovery of a 3rd partner (yeast) in many Lichen: http://theconversation.com/lichens-may-be-a-symbiosis-of-three-organisms-a-new-order-of-fungus-named-63334