POD RACERS

TWICE A MONTH, on Thursday mornings, Tad Yankoski listens for a doorbell. A priority package that left Costa Rica three days earlier is due at the Butterfly House in Chesterfield by 10:30 a.m. When it arrives and the FedEx driver presses the button to trigger the buzzer, Yankoski, a senior entomologist, hurries to the delivery door, retrieves a 2-foot cube shipping box, and rushes it to his laboratory’s quarantine space. “It’s very much a race against time,” he says.

That’s because the approximately 200 blue morpho butterflies inside are in their chrysalis stage