Brought to you by Newscorp Australia

Indonesia’s fierce komodo dragons have the rare ability to produce young without male mates

Donna Coutts, March 11, 2020 7:00PM Kids News

Print Article
Komodo dragon on Rinca Island, Indonesia. Komodos are the biggest lizards in the world. Picture: iStock media_cameraKomodo dragon on Rinca Island, Indonesia. Komodos are the biggest lizards in the world. Picture: iStock

animals

Reading level: green

A female komodo dragon has produced three baby dragons without a male mate.

Komodo mum Charlie lives at Chattanooga Zoo in Tennessee, US and produced three brothers named Onyx, Jasper and Flint through a rare process called parthenogenesis. Only 70 known veterbrate* species can do this, which is 0.1 per cent of all known vertebrates, according to Scientific American.

The ability was first noticed in komodo dragons in 2006.

Charlie and a potential mate named Kadal were put together in an enclosure last year in the hope they would produce young dragons.

The hatchlings were born last August but because the zoo keepers couldn’t confirm whether Kadal and Charlie had mated, they turned to DNA testing to find out if the young were related to Kadal.

“Kadal, you are NOT the father!” Chattanooga Zoo announced on a Facebook post.

“Our staff is thrilled to play a part and to be able to witness this truly miraculous occurrence,” the zoo’s president and CEO Dardenelle Long said in a statement.

“As the Komodo dragon is listed as vulnerable to extinction, these hatchlings are even more special and represent a bright future for their species.”

In the wild, Komodo dragons live alone and are very aggressive (scaring off or injuring possible mates), so they need to be able to reproduce without a mate.

Komodo dragons can also reproduce with a mate.

The Komodo dragon. Scientific name: Varanus komodoensis. media_cameraKomodo dragons on Rinca Island, Indonesia. The species’ scientific name is Varanus komodoensis. Picture: iStock

KOMODO DRAGONS
They live on several volcanic Indonesian islands.

Males can grow up to 3m long and weigh 100kg.

They are fierce carnivores* eating everything from insects, monkeys, deer, dead animals of any sort and even other komodo dragons.

They are listed as vulnerable to extinction due to habitat loss, volcanic activity and poaching.

Source: Australian Reptile Park

A Japanese Komodo dragon prowling in the sand media_cameraKomodo dragons are fierce carnivores that even eat their young.

PARTHENOGENESIS
This is a normal way to reproduce for many plants and a few animals.

In bees, parthenogenesis produces drone bees.

In animals, it happens when an egg in a female is fertilised by another egg from the same female, rather than by a sperm cell from a male.

Female komodo dragons have sex chromosomes in their cells called WZ.

Chromosomes are threadlike structures in a cell in a living thing that carries DNA, which is genetic information.

Male komodos have ZZ sex chromosomes.

If a female and a male mate, they can produce either females (WZ chromosomes) or males (ZZ).

If a female komodo produces young by parthenogenesis, they can only make young with WW or ZZ chromosomes. WW eggs aren’t viable*, so only male dragons can be born by parthenogenesis.

A Komodo Dragon hatchling that's part of group of 22 that recently hatched last month at the Los Angeles Zoo, on September 23, 2010. Hatchlings are 14 to 20 inches long and weigh about three to four ounces. Komodos, the world?s largest lizard, can grow to approximately nine feet, weighing up to 200 pounds or more. Because Komodos are cannibalistic, readily eating the young and eggs of their own species, hatchlings are on their own from the start. In the wild, just after hatching the young scurry up nearby trees to avoid being eaten by the adults and remain in the trees, feeding on insects and small lizards, until they are too heavy to forage successfully up above. AFP PHOTO/Mark RALSTON media_cameraA komodo dragon hatchling born as part of a clutch of 22 in 2010 at Los Angeles Zoo, US. Because komodos are cannibalistic, they sometimes even eat their own young. Just after hatching they scramble up trees to avoid being eaten and stay there eating insects until they grow enough to look after themselves on the ground. Picture: AFP

GLOSSARY

  • vertebrate: has an internal skeleton
  • carnivores: eat meat
  • viable: don’t work well enough to survive

EXTRA READING

Australias surprising supermum skink

Last Galapagos tortoise helping humans

Mystery of the 7m python skin in the park

Fossilised ‘iron dragon’ found in the outback

QUICK QUIZ

  1. What did this komodo dragon do to make the news?
  2. Who or what is Kadal?
  3. What do komodo dragons eat?
  4. Why is this species listed as vulnerable?
  5. What are chromosomes?

LISTEN TO THIS STORY

CLASSROOM ACTIVITIES
 1. Design a poster
Write a list of the most important things about komodo dragons you have learned from this article. Then, design a poster that will help other kids understand why komodo dragons are so amazing. Use your list to help you to decide what to include in your poster

Time: allow 30 minutes to complete this activity
Curriculum Links: English, Science, Visual Communication Design.

2. Extension
Write a story that starts with these sentences: ‘Anybody can have a dog or a cat as a pet. My family wanted something different, so we decided to get a komodo dragon.’

Time: allow at least 25 minutes to complete this activity
Curriculum Links: English, Critical and Creative Thinking

VCOP ACTIVITY
 With a partner see if you can identify all the doing words/verbs in this text. Highlight them in yellow and then make a list of them all down your page. Now see if you and your partner can come up with a synonym for the chosen verb. Make sure it still makes sense in the context it was taken from.

Try to replace some of the original verbs with your synonyms and discuss if any are better and why.

HAVE YOUR SAY: What is your favourite reptile?
No one-word answers. Use full sentences to explain your thinking. No comments will be published until approved by editors.

Extra Reading in animals