Leap frogs for Leap Day!

Posted by: Kirsten Pisto, Communications
Video and photos by: Jeremy Dwyer-Lindgren/Woodland Park Zoo

Every four years, Leap Day occurs on the 29th of February to round out our Gregorian calendars. With 6 extra hours accumulating each year, Leap Day serves as an “extra” day to make up for our not-exactly-even trips around the sun. 

To help fill your 24 leaping hours, we bring you a closer look at the anatomy of a leap. With a little help from some very special creatures, a slow motion camera and a lot of patience (have you ever tried directing a frog?) here is a closer look at what it takes to leap.

A frog’s leap can make the difference in its survival, the difference in becoming prey or catching prey. With a myriad of potential predators, including birds, fox, cats, snakes and people, as well as a host of elusive prey such as crickets, spiders, worms and fish—it’s no wonder frogs have mastered the art of a fast leap.

Whether in an attempt to elude a predator or catch a bite, frogs rely on their long legs and super-ability to launch themselves into the air. Some species can jump up to 50 times their body length. In comparison, a person with this ability would be able to leap across a football field without a running start.

Waxy monkey frog. Frogs typically shut their eyes right before they leap. This protects their eyes during the jump. Their back feet stay on the ground as long as possible to maximize the push-off.

Waxy monkey frog. The longer their legs stretch out during the leap, the more power is directed into the elastic tendons. At the same time, their front legs fold in towards their belly.

Depending on the species’ diet and environment, their jump may be more or less extreme. Although still impressive, a bullfrog might only jump 10 times its body length, while some species of tree frogs have been recorded jumping at 50 times their length. Toads and burrowing frogs rely less on jumping and instead camouflage themselves in mud or water. Similarly, a tree frog might jump really high vertically, but an aquatic frog will jump farther in length. 

Solomon Island leaf frog, Ceratobatrachus guentheri.

While not all frogs or toads jump, those that do can thank their tendons for their leaping ability. The secret to a proper leap is in the wind up. A frog’s long legs and powerful muscles are helpful, but the trick to leaping is hidden in elastic storage. When its leg muscles contract, the frog’s tendon is pulled tight much like when a rubber band is pulled tight between your fingers. When the tension is released, a trigger of energy is created. When a frog is crouching in its normal position, the energy is being stored, but when it shifts into a straight leg pose, the frog is catapulted forward as the tension is released.

Like a spring coiled and ready for release, a frog’s muscles transfer energy into their tendons right before they jump, which allows them to jump far higher than muscles alone. Of course, this all happens in less than a fifth of a second, sometimes faster, so seeing this movement without the help of a slow-motion camera would be difficult.

Denny's (or Chinese) flying frog. Leap Day has long been linked to folklore and superstition. Some considered it lucky and others avoided the day.

If you’d like to experience your own human elastic storage, try throwing a baseball overhand. Your ability to rapidly release your shoulder is using the same mechanics as a frog’s leaping legs.

Giant leaf frog, Phyllomedusa bicolor.

Giant leaf frog, Phyllomedusa bicolor.

Happy birthday to all the leaplings out there and here’s to a lucky Leap Day!

False tomato frog, Dyscophus guineti

For a closer look at leaping, visit the Day Exhibit or the Tropical Rain Forest for a chance to study this awesome amphibian adaptation for yourself. Frogs are beautiful, but unfortunately they are part of the most endangered group of land animals in the world—amphibians. Visit today and learn how you can help protect amphibians and their habitat from pollution, invasive species and infectious diseases. Each visit to the zoo helps to support our work with amphibian conservation in Madagascar and with other researchers around the world.