From a South American frog to a Russian penal colony: How the poison epibatidine killed Navalny

This extremely powerful neurotoxin is secreted by a frog native to Ecuador. Although Western scientists discovered it in the 19th century, it wasn't synthesized until the 1990s. The neurotoxin appears to have particularly interested the Russian research institute responsible for synthesizing Novichok agents, used in poisonings.