Amazing Places

Snake Island Is Teeming With Nothing But Outrageously Venomous Snakes

Some names really say it all. You shouldn't have to do much research to decide if you'd like to go to "Gumdrop Mountain." Likewise, you wouldn't expect to have to warn people to stay away from "Snake Island." But if you manage to find your way there, you'll find a place where the most toxic bite rules.

A Hiss-tory of Vipers

According to some estimates, there's about one snake per square meter on Ilha da Queimada Grande (as it's properly called in Portuguese) and up to 4,000 of those are deadly golden lancehead vipers. Legends say that pirates brought the snakes themselves in order to protect the treasure they'd hidden on the island, but in reality, the snakes have been there for thousands of years.

In fact, the snakes of Snake Island have been there since before it was an island. 11,000 years ago, rising water levels turned a peninsula into an island, leaving the snakes stranded to evolve on their own. With no land predators to worry about, the snakes had it made. There was just one problem: They didn't have any land prey to eat, either. There were birds, and that fact shaped the evolution of the golden lancehead over the next few thousand years. Evolving to dine on their feathered neighbors gave the snakes one of the most toxic bites in the animal kingdom.

The Baddest Bite

The birds that land on Snake Island aren't giants, and they aren't particularly resistant to poison. So why did these snakes need to develop one of the strongest venoms on the planet? The answer is speed. While most venomous snakes can sink their teeth into their prey and then wait for the toxin to take effect, the golden lancehead's meals will fly back to the mainland if given half a chance. That's why their venom has to work so quickly — the fact that it's literally strong enough to melt human flesh is an unintended side effect.

Humans Keep Out

You might not expect a place that's literally crawling with deadly snakes to require a warning, but the government of Brazil has found it necessary to do so. It's not just for the people's sakes either — the golden lancehead is listed as critically endangered, and this is the only place in the world that it lives. That's why it's illegal for people to visit the island, with the exception of the herpetologists that study the wildlife from their on-site labs and the Brazilian navy's annual trip to keep the island's lighthouse in order.

You don't have to tell us twice. 

Get stories like this one in your inbox or your headphones: sign up for our daily email and subscribe to the Curiosity Daily podcast.

Ever wonder how venoms work, and how so many different kinds of animals have so many different kinds of toxins? Check out Christie Wilcox's "Venomous" to get up close and personal with the world's deadliest bites. The book is free with a trial membership to Audible. We handpick reading recommendations we think you may like. If you choose to make a purchase through that link, Curiosity will get a share of the sale.

Snakes ... Snakes Everywhere

Written by Reuben Westmaas March 30, 2018

Curiosity uses cookies to improve site performance, for analytics and for advertising. By continuing to use our site, you accept our use of cookies, our Privacy Policy and Terms of Use.