Original: Venom has been known in the families Caenophidia , Anguimorpha , and Iguania and has been shown that it evolved a single time along these lineages before the three families diverged because all lineages share nine common toxins .
Simplified: Venom in the families Caenophidia , Anguimorpha , and Iguania evolved once , then the three families diverged . All three lineages share nine common toxins .