11. Opossum

The largest order of marsupials in the Western Hemisphere, the Opossum is known to be immune to some snake venoms. In lab experiments with mice, a team discovered the exact molecule, called a peptide, in the Opossum’s blood that can neutralize snake venom. The peptide worked against several venomous snake species, including the western diamond back rattlesnake and the Russell viper. The Opossum is also immune to ricin and botulinum toxin.