Please, please, if you've never done so, watch this video of the common basilisk, aka the 'Jesus Christ lizard', running on water.
What you’ll witness is a scene from Looney Tunes played out in real life, with a lizard instead of the Road Runner, but seemingly just as immune to the laws of physics.
Common basilisks are native to Central and South America, where they live in rainforests, near rivers and streams. These are relatively small lizards with big tails, more than twice the length of their body.
Males can grow to a total length of around 75cm (about 30in) and have three distinct, sail-like crests: one on the head, one on the back and one on the tail.
They are territorial and use these large, dramatic crests to establish dominance and attract the smaller females.
Their defining feature, though, is their ability to run on water, which they do to avoid predation. This is an innate skill. Youngsters don’t need instruction. They hatch with the ability.
Over short distances of up to 20m (66ft), adults can run at speeds of around 5km/h (3mph), but younger, smaller, lighter basilisks can go faster still.
They run on their back legs with their forelimbs flailing like Kermit the Frog, prompting researchers to dispute the improbability of it all.
Enter, biologist Tonia Hsieh.
In 2003, while studying for a PhD at Harvard University, she used high-speed cameras to film 30 basilisks running on water in a 4.6m (15ft) tank. Then she compared their locomotion to that of ground-running lizards.
Common basilisks run in a very peculiar way.
On water, they sweep their feet more widely to the sides and extend their legs much farther behind their body than they do to the front. They also keep their legs relatively stiff, slapping their feet onto the water like a piston.
A follow-up study, the next year, showed that each footstep produces enough force to support the basilisk’s body weight and propel them forwards.
The strongest forces are generated during the first half of each stride when the foot moves vertically down into the water. This ‘slap’ pushes the water down and away, generating a pocket of air around the temporarily submerged foot, reducing drag.
This helps the basilisk to extract its foot from the water and keep on moving.
The common basilisk is a master of fluid dynamics, but alongside its locomotory adaptations, evolution has equipped it with physical adaptations too.
The hind legs are elongated and muscular, and the large hind feet have scaly fringes on the sides of the third, fourth and fifth toes.
These skin flaps are folded against the toes when the lizards walk on land, but on water, they open to provide the foot with extra surface area.
All in all, the Jesus Christ lizard is weird, but wonderful.
Other animals, including pond skaters, fishing spiders and some grebes (diving birds), may walk or run on water, but none do it with the flair of the common basilisk.
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