This is the fifth episode in our series on predator-prey interactions. In this episode, we explore two real-world examples of coevolution that didn’t just shape species-but transformed ecosystems and economies.
First, we follow the story of Rodolia cardinalis (Vedalia beetle) and Icerya purchasi (cottony cushion scale)-a predator-prey relationship that kept the scale insect in check for millennia in Australia. But when the scale was accidentally introduced to California in the 1870s, it wreaked havoc on citrus orchards, causing an 80% decline in yields. Enter biological control pioneer Charles Valentine Riley, who sent entomologist Albert Koebele on a mission to find the scale’s natural en...