What's A Meaningful Eco-Evo Interaction?

Answer: one that describes a causal loop from ecological state to selective milieu to new ecological state to new selective milieu.  Defined this way, eco-evo interactions are less widespread than claimed but more interesting than is often appreciated.  These interactions are based on successful genotypes that, through their effects on the environment (defined broadly), sow the seeds of their own eclipse at the hands of different genotypes.  An interaction that doesn’t traverse the entire loop ought not be labeled as an “eco-evo interaction” lest the concept become trivial. An introduction experiment with guppies illustrates this point.