After a deadly fungus spread through the rainforests in southern Chile, conservationists embarked on a rescue mission to save Darwin's frog.

Sixty-two years after Attenborough's long-beaked echidna was last scientifically recorded, Expedition Cyclops went on a mission to find out whether the species still exists in the Cyclops Mountains.

Having roamed since the Ice Age, Saiga Antelope are no stranger to harsh conditions. But as mass mortality events leave their population extremely vulnerable, how have they managed to make countless comebacks?