Late Ordovician Extinction Mystery Solved

"Familiar Culprit May Have Caused Mysterious Mass Extinction":

It has long been our planet’s greatest and oldest murder mystery. Roughly 445 million years ago, around 85 percent of all marine species disappeared in a geologic flash known as the Late Ordovician mass extinction. But scientists have long debated this whodunit, in contrast to clearer explanations for Earth’s other mass extinctions.

My money was on Colonel Mustard in the kitchen with the candlestick.