Episode 186 – Komodo Dragon: A Toxic Debate

“…and today we’re talking about the closest thing to a traditional fire breathing dragon we’re going to get.”

Reptilians once dominated the food chain as the largest animals in their ecosystems until some natural checks and balances relegated them to smaller bodies that were better at sneaking under rocks and bushes. But nature’s memo failed to reach one island in Oceania. The Komodo dragon is a giant that lives at the top of their ecosystem, capable of taking down even large prey animals. But these unique lizards may have a tool up their sleeve besides their size. But pairing a high weight class with some unique talents is the best way to rule in Life, Death, and Taxonomy.  

Description of the Komodo Dragon

  • The Komodo dragon is the largest lizard alive today.
  • And, in fact, it looks like a giant version of the lizards you might find sunning themselves on your front porch.
  • They have long bodies and necks with short legs tipped with sharp claws for digging and tearing. 
  • Their tales are thick and muscular like a crocodile’s and end at a point for maximum whipping potential.
  • Their heads look like they were the direct inspiration for Godzilla with rounded snouts, beady black eyes, and a wide mouth filled with sharp, serrated teeth and a forked tongue that I wish Grima Wormtongue had.
    • Just like the tuatara, the Komodo dragon also has a third eye (the pineal eye) to potentially sense certain types of light. But this one is virtually invisible.
  • Their black/grey/rust-colored skin is made up of these hardened scales called osteoderms. As the name suggests, it has bone skin. The scales are reinforced with tiny bones.
    • These scales appear during adulthood and grow harder with age like a fine whiskey or Sam Elliot

Measure Up

Welcome to the beloved Measure Up segment. The official listener’s favorite part of the show! The part of the show when we present the animal’s size and dimension in relatable terms through a quiz that’s fun for the whole family. It’s also the part of the show that’s introduced by you when you send in audio of yourself saying, singing, or chittering the words Measure Up into ldtaxonomy at gmail dot com. We don’t have a new Measure Up intro!

  1. Texel Sheep
  2. Giant Panda
  3. Gila monster
  4. Giraffe


  • 2.59 m (8.5 ft)
  • How many komodo dragons go into the length of the longest ever monster truck?
  • Hint: The truck is called the Sin City Hustler and it boasts a 750-hp engine. It was built by Brad and Jen Campbell to be a novel limousine for tourists in Las Vegas.
  • 3.7 komodo dragons. The truck is 9.8 m (32 ft) long.


  • 70 kg (150 lb)
  • How many Komodo dragons go into the combined weight of soldiers treated by Marie Curie’s mobile radiology units (called petites Curies) in World War I.
    Hint: Marie Curie is the first woman to receive a nobel prize and the only woman to have the prize in two different fields. During the first world war she realized that soldiers needed surgery as soon as possible and pioneered field surgical centers with X-ray machines. Assume the soldiers weighed 170 pounds. 
  • 1,133,333 komodo dragons. The combined weight of a million soldiers is around 170,000,000 pounds.

Komodo Dragon Fast Facts

  • Range: the islands of Indonesia, particularly Komodo, Rinca, Flores, and Gili Motang. 
  • Diet: They mainly eat a species of Indonesian deer called Javan Rusa. They also will eat just about any scavenged corpse they find and will sometimes even eat the young of other dragons. They’ll also eat eggs, birds, monkeys, goats, boars, and even large animals like horses and water buffalo.
  • Behavior: 
    • They can live for up to 30 years
    • It will eat up to 80% of its body weight in one meal and then sits in the sun to digest.
      • They have a slow metabolism which allows them to eat as little as once a month, but they need to warm up or the food will rot in their stomachs and poison them (again, like crocodiles in winter)
    • They can be aggressive toward humans and have fatally wounded or possibly eaten several people according to reports.
  • Under certain circumstances where females are isolated, they can actually reproduce asexually – much like the mourning gecko.
    • So they can lay eggs without knocking any boots. 
    • This is called parthenogenesis and only males are produced in this way.

Major Fact: Toxic Drool

Komodo dragons are the largest lizards in the world. They’re thought to reach that size because of something called insular gigantism, which is when an isolated species grows larger than their wider-world kin.

Their large size makes them unable to sustain high speeds for long, but they are built for ambush. Dragons wait at ambush sites and spring on victims and overwhelm them with lacerating bites. 

In most cases, they kill prey in 30 minutes. In some cases, larger prey can shake off a dragon and get away. But reports say that escaped prey often dies within a few days, and then they are swarmed by hungry dragons.

You may have heard komodo dragons can do this because their bite is toxic. Legend has it that a komodo dragon’s saliva contains deadly bacteria that comes from the rotting chunks of flesh in their teeth from former meals. Conventional wisdom suggests that a single bite can make an animal fatally sick from this bacteria. 

But that’s not true.  

Some studies did find dangerous bacteria in komodo mouths, but it probably isn’t due to poor oral hygiene. Dragons apparently spend a solid 15 minutes cleaning their mouths after a meal. They will lick their lips and rub their face on dried leaves to remove excess blood and meat.

So if that’s true, why does wounded prey die?

One of the simplest explanations is that they die from infected wounds because animals with open wounds often die from infections. Komodos attack prey by inflicting lacerations from bite, not by efficiently killing blows like lions or leopards. These deep wounds typically cause animals to bleed out, but if not, it could cause infections. CErtain prey, like water buffalo, run to water when threatened. Running into unclean water with open wounds can cause them to become infected. 

However, there is another potential explanation. 

In 2005, researcher Bryan Fry found venom genes in Komodo dragons, and then in 2009 an MRI on a dragon skull found glands that could contain venom. They later took the gland out of a sick komodo and found that it contained venom proteins that could stop blood clotting and lower blood pressure. This could increase the speed an animal bleeds to death, making the komodo at least slightly venomous. 

But critics of these findings suggest that there are many purposes these proteins could serve in a reptile mouth, and may not be used as a venom. 

Ending: So enjoy sunny days, keep your toxic spit to yourself, and only swallow your prey whole if you have a special tongue lung tube like the Komodo dragon here in Life, Death, and Taxonomy.