NOVA Mystery Beneath the Ice airs on WSKG TV at 9pm. The population of krill has crashed since the 1970s for reasons that continue to baffle the experts. These delicate, transparent, shrimp-like creatures are crucial to the Antarctic ecosystem and, maybe, to the future of all our oceans. Could the krill’s life cycle be driven by an internal body clock that responds to the waxing and waning of the Antarctic ice pack? As climate change alters the timing of the ice pack, their life cycle is disrupted—or so the theory goes.