Anomalcaris was the very first apex predator. Before Anomalcaris appeared, the ecosystem was probably in mass chaos. With no apex predators around to eat the animals, populations likely went above the limits. But as the Precambrian came to a close, the curtains to the Cambrian opened and Anomalcaris came to the scene. Now that the apex predator came along, all Anomalcaris had to do first was to lower the animal populatation a little. The ecosystem was finally balanced. Because Anomalcaris was an apex predator, there nothing around tough enough to attack him except his own kind. What this meant was life in the Cambrian always had someone around the block to keep the ecosystem healthy.