How did the innate immune system evolve?

Sexually Antagonistic Male Signals Manipulate Germline and Soma of C. elegans Hermaphrodites Abstract excerpt: Why would a system exist that reduces the vigor of potential mates prior to mating? Addressing this question could provide insights into mechanisms and evolution of sexual conflict and reveal sensory inputs that regulate aging. Highlights excerpt: An unknown signal accelerates larval … How did the innate immune system evolve?