Why Do Lizards Do Pushups? 7 Strange Facts You Didn't Know About the Reptiles

Lizards, with their extraordinary variations, have helped transform what ecologists thought possible in a single species.

Boasting more than 7,000 different types, the reptiles are found around the world and range widely in size, scale and—often bizarre—abilities.

Martin Whiting, professor of animal behavior at Sydney's Macquarie University, gave Newsweek his thoughts on why lizards are of enduring interest to experts.

He said: "Lizards have long been a source of fascination to naturalists and scientists alike because of their extreme variation in body size, form, behavior, and the remarkable ways they have adapted to their environments.

"More recently, scientists have used them to understand key life processes, including natural selection. From studies of lizards, we have a far greater understanding of how animals respond to significant changes in their environment, which is a big issue in an era of global warming and urbanization."

Why do lizards do pushups and can they swim? Read on to learn some fascinating facts: from their weird rituals to their hidden talents.

1. Why Do Lizards Do Pushups?

Grabbing another's attention can always be tricky, especially from a distance.

However, lizards have evolved a successful head-turning technique to do just that.

Dr. James Stroud, Postdoctoral Researcher at Washington University in St. Louis, said many lizards have developed an exhausting ritual as they "cannot make noise to communicate."

He told Newsweek: "Some lizards, such as tropical iguanas or American fence lizards, instead do pushups.

"This behavior conveys information about that individual, like how strong and fit they are, as both a warning to potential competitors and to attract potential mates."

2. Some Lizards Wave 'Flags'

One young bearded dragon in a terrarium
One young bearded dragon in a terrarium Shinedawn/Getty Images

Owners of lizards such as the Bearded dragon, will know its name bellies its gentle and relaxed nature, which is known for occasionally giving onlookers an apparently cheerful "wave".

Dr. Stroud said: "Instead of doing pushups, some lizards have evolved a more elaborate way to visually communicate.

"These species are able to extend flaps of skin under their chin, throat fans known as 'dewlaps', and perform beautiful display patterns, advertising their attractiveness to other lizards."

3. Some Lizards Have Sticky Toes

Young crested (Caledonian) gecko on leaf
Young crested (Caledonian) gecko on leaf Cavvy01/Getty Images

Anyone who has witnessed a reptile scale a wall, building or tree with unnerving ease knows lizards possess some unbelievable climbing skills.

Dr. Stroud states this seemingly gravity-defying ability is because lizards have evolved special anatomy.

He said: "Some lizards, like geckos and Anole lizards, have evolved sticky toes that enable them to hold on better to slippy surfaces high in the treetops, such as the smooth sides of leaves.

"My own research has explored how these sticky features have evolved more than once in different types of lizards."

4. Some Lizards Can 'Fly'

Draco lizards flying or gliding in rainforests
Draco lizards flying or gliding in rainforests in Thailand NeagoneFo/Getty Images

Life is perilous in the jungle, meaning animals unable to fight back against predators must evolve clever new methods of escape.

Dr. Stroud said one lizard has taken the term "fight or flight" to a literal level.

He said: "In the rainforest of southeast Asia, there is a peculiar group of lizards with a unique ability: they can "fly".

"The flying dragon lizards, known as 'Draco', have flaps of skin between their front and hind legs that can be opened out like a parachute, enabling these lizards to glide from tree to tree in the rainforest."

5. Some Lizards Have Green Blood

Why Do Lizards Do Pushups
Some lizards (note: not the one pictured) have green blood running their veins, although the evolutionary advantage this gives remains unclear Viktoryia Voinakh/Getty Images

Like most animals, nearly all lizards have red blood. However, Dr. Stroud points one "peculiar" lizard living deep in the rainforest of Papua New Guinea is an anomaly: its blood runs green.

He said: "The Latin name given to this species represents this weird fact: Prasinohaema [means] Green (Prasino-) blooded (-haema)."

And a study published in 2018 suggests this bizarre lime-green blood has evolved independently several times in lizards.

Experts hope by understanding how these weird reptiles might benefit from green blood may eventually offer insights into human illnesses such as jaundice and malaria.

6. Some Lizards Can Swim Underwater

monitor lizard swimming
A Monitor lizard swimming in Queen Sirikit Park in Bangkok Lillian SUWANRUMPHA / AFP/Getty Images

Dr. Stroud states while most lizards live on land, everywhere from searing deserts to the most humid rainforests "some lizards have evolved to specialize for a wet life."

He said: "In the Galápagos, marine iguanas swim in the sea and dive underwater to feed on algae growing on submerged rocks.

"While in the rainforest of Costa Rica, the aquatic Anole lizard is able to re-breathe air in its lungs like a scuba diver, allowing it to hide underwater when escaping from predators."

7. Some Lizards Can Extend Their Tongues to Catch Food

Chameleons' tongues are longer than their bodies
Chameleons' tongues are often longer than their bodies and can fire from their mouths at astonishing speeds CathyKeifer/Getty Images

Standing at the apex of extraordinary animals is the Chameleon, a lizard species able to change its color as a remarkable form of social signalling.

But if that was not incredible enough on its own, the reptiles can also famously flick their long, sticky tongues to catch their meal as it eventually lands.

Dr. Stroud describes this as "a really cool feature", adding: "They are able to shoot out their tongue to catch insects from afar, allowing them to stay hidden and be much more successful hunters."

A 2016 study found this is achieved by the chameleon releasing its tongue muscles, in turn allowing its tongue to spring forward and capture its insect.