Rethinking Mutualism Stability: Cheaters and the Evolution of Sanctions

Citations Over TimeTop 1% of 2013 papers

Abstract

How cooperation originates and persists in diverse species, from bacteria to multicellular organisms to human societies, is a major question in evolutionary biology. A large literature asks: what prevents selection for cheating within cooperative lineages? In mutualisms, or cooperative interactions between species, feedback between partners often aligns their fitness interests, such that cooperative symbionts receive more benefits from their hosts than uncooperative symbionts. But how do these feedbacks evolve? Cheaters might invade symbiont populations and select for hosts that preferentially reward or associate with cooperators (often termed sanctions or partner choice); hosts might adapt to variation in symbiont quality that does not amount to cheating (e.g., environmental variation); or conditional host responses might exist before cheaters do, making mutualisms stable from the outset. I review evidence from yucca-yucca moth, fig-fig wasp, and legume-rhizobium mutualisms, which are commonly cited as mutualisms stabilized by sanctions. Based on the empirical evidence, it is doubtful that cheaters select for host sanctions in these systems; cheaters are too uncommon. Recognizing that sanctions likely evolved for functions other than retaliation against cheaters offers many insights about mutualism coevolution, and about why mutualism evolves in only some lineages of potential hosts.

Related Papers

• → An emerging view of coevolution in the legume–rhizobium mutualism(2023)8 cited
• → Figs and fig pollinators: evolutionary conflicts in a coevoled mutualism(1997)165 cited
• → Coevolution in mutualisms(2015)16 cited
• → Mutual cheating strengthens a tropical seed dispersal mutualism(2021)12 cited
• → Grasses, Grazers, Mutualism and Coevolution: A Comment about Handwaving in Ecology(1983)27 cited