Here’s why some snakes are deadlier than others

Washington: It turns out that some snakes are deadlier than others, according to a new study. Snakes are infamous for possessing powerful venom, however, some species, such as cobras, rattlesnakes and boomslangs, have far more venom than they apparently need.

In a study was conducted by an international collaboration led by scientists from the National University of Ireland, Galway, The University of St Andrews, Trinity College Dublin and the Zoological Society of London scientists tried to figure out why venoms vary so much in their ability to kill or incapacitate potential prey animals.

The study has been published in the international journal Ecology letter.

The study, tackled this puzzle by comparing records of venom potency and quantity of over 100 venomous snake species.

The team found evidence that the venoms have evolved according to what species the snake commonly eats.

Speaking about the study, lead author Dr Kevin Healy said, “These results make sense from an evolutionary viewpoint as we expect that evolution will have shaped venoms to be more efficient at killing the prey animals they are most often the target of the venom. You won’t find many mice in the sea so we wouldn’t expect a sea snake to evolve venom that is more effective at killing mice than fish.”

The study also went on to show that the amount of venom a snake has depends on both its size and the environment it lives in.

Associate Professor in Zoology at Trinity College Dublin, Dr Andrew Jackson added that like all substances, venom is dosage-dependent and that even alcohol, coffee and water can be toxic at high enough volume. Thus the researchers needed to consider how much venom different species of snake produce and store in their venom glands.

He added, “We found that big terrestrial species have the most venom, while smaller tree dwelling or aquatic species had the least. This difference may be due to how often a snake encounters its prey in these different environments, with terrestrial species requiring a larger reserve of venom to take advantage of the rarer opportunities to feed.”

The results of the study also have potential to aid in the understanding when it comes to human snakebites.

Commenting on it, Dr Chris Carbone said, “Understanding how venom evolves may help us better identify the risks to humans from different snake groups, and also potentially from other venomous animals such as spiders, scorpions, centipedes and jellyfish.”

The approach used in the study may also help researchers predict the potency of venoms in species that have yet to be tested, and even pinpoint potentially useful healthcare-related applications.