Why Russia may have turned to dart‑frog toxin epibatidine to poison Navalny

Two years after Russian opposition leader Alexei Navalny died in prison, five European countries claim they have identified the substance that killed him: epibatidine, an extremely lethal toxin produced by the South American poison dart frog. But why go through the trouble of using such a rare, exotic poison naturally found only on the other side of the world? Some experts believe Navalny may have been used as a lab rat.