The saiga antelope walked alongside woolly mammoths and survived the Ice Age, yet in 2015 more than 120,000 of them dropped dead in a matter of weeks. This episode explores one of the most resilient and bizarre survivors on Earth, an animal that is simultaneously classified as critically endangered and treated as an agricultural pest, and how its rollercoaster history reveals the fragility of modern ecosystems.

We examine the saiga's strange proboscis and its dual role filtering summer dust and warming winter air, then trace its near-extinctions, its exploitation under the Soviet system, and the conservation blunder that painted a target on its back. We unravel the mystery of the 2015 mass die-off and the species' astonishing recovery to over a million animals.

• How a ban on rhino horn led conservationists to promote saiga horn as ...