The Jesus Christ Lizard Is So Named Because It Can Run on Water

Deep in the lush rainforests of Central and South America, an incredible reptilian creature dwells that seems to defy the laws of physics – the Jesus Christ lizard. Also known as the common basilisk (Basiliscus basiliscus), this remarkable reptile (and also other members of its genus) has an almost supernatural ability that has earned it its rather fitting name – it can literally run across the surface of water.

At first glance, the Jesus Christ lizard may not seem all that extraordinary compared to other lizard species in the region. Their gaze holds no deadly power and their breath is not poisonous like the mythical basilisks of legend. However, these brown and olive-colored reptiles with distinctive light stripes have developed some truly remarkable traits over the course of evolution.

Reaching up to 75 cm (2.5 feet) in total length, these lizards typically make their homes along the riverbanks and lakeshores winding through the rainforests. Here they feed on a diet of insects, flowers, eggs, small vertebrates and more plucked from the leafy undergrowth.

To keep their cold-blooded bodies operational each day, the basilisks bask in the sun’s warming rays. But this also makes them extremely vulnerable to falling prey to the numerous hungry predators stalking the forest floors – bird, reptile or mammal.

It’s precisely to escape such threats that the basilisks evolved their incredible bubble-running skills and earned their biblical nickname. When a basilisk senses danger, it quickly flees to the nearest water source and simply keeps running across the surface rather than stopping at the bank. Here’s what it looks like in practice.

For years, scientists suspected this amazing feat was based on somehow exploiting water’s surface tension, but couldn’t fully explain how. That finally changed when BBC crews captured 2,000 frame-per-second footage of the brown basilisk species, allowing them to meticulously analyze the lizard’s movements in slow motion.

What they observed was the basilisk’s ability to create a pockets of air beneath its large, specialized hind feet as they slap down onto the water’s surface at rapid speed. The feet have fringed scales along the toes that splay out when the lizard hits the water, increasing their surface area to essentially run on the bubbles.

As producer Simon Blakeney described it, the basilisk moves so fast that its churning feet create new air cavities just before the previous bubbles pop. This cyclical slapping and stroking motion propels the lizard forward in a sprinting stride unlike anything else in nature.

Researchers have found that basilisks also create powerful sideways forces with their high-stepping strides, allowing them to remain upright while water-running rather than simply skimming across on all fours. Every aspect of their physicality and rapid movements appears uniquely adapted for this semi-aquatic talent.

To avoid sinking, the lizard must maintain breakneck speeds of around 5 meters per second. Younger basilisks can pull off astounding waterborne runs of 10-20 meters before becoming too heavy and eventually swimming. The lizards are skilled swimmers able to stay underwater for up to 30 minutes when necessary to evade pursuers that follow them into the water.

But it’s their bizarre bubble-running trick that has cemented the basilisks’ fame and incredible name. Like a real-life interpretation of the biblical miracle, these lizards appear to basically defy gravity for short bursts by running across the river or lake before their bodies plunge below the surface once more.

Sources: 1, 2