The crown-of-thorns is a venomous starfish that lives in the Great Barrier Reef. Growing up to massive lengths of 80 centimetres and having a body entirely covered in toxic spikes, the starfish is almost indestructible and is a vicious predator. They eat coral, the building blocks of the Great Barrier Reef. It’s said that one adult starfish can eat up to ten square metres of coral every year.
Recently populations of crown-of-thorns starfishes have been exploding and as a result the corals are in more danger than ever. The starfish are responsible for causing 40 per cent of all coral damage, making them one of the biggest threats to the Great Barrier Reef today.
But hope is not lost for the coral reef. Scientists Matthew Dunbabin and Feras Dayoub created an autonomous robot called COTSbot to minimise crown-of-thorns starfish populations and rescue the reef.
The robot is equipped with a number of thrusters and stereoscopic cameras, allowing it to search for the venomous starfish and kill them. Matthew and Feras trained the COTSbot through various YouTube videos, as well as thousands of images of the starfish by divers currently doing manual injection of the starfish on the Great Barrier Reef.
The COTSbot was trained for six months, to the point where it can identify crown-of-thorns starfish on its own. Once the starfish has been identified, the robot then injects it with bile salts, a protein that kills the starfish. The COTSbot can inject up to two hundred starfish and remain in the water for up to eight hours. Scientists hope that the COTSbot will be able to help protect corals and save the Great Barrier Reef.
CSIRO Publishing now do children's books! Our first book is Phasmid: Saving the Lord Howe Island Stick Insect. With a captivating story by Rohan Cleave, invertebrate zookeeper at Melbourne Zoo, and stunning watercolour illustrations by renowned artist Coral Tulloch, Phasmid is about survival in a time of worldwide species decline. Sign up to our new children's book email alert to stay informed about all of our exciting projects.
Try this:Cool crystals
You will need
Cup or mug
½ cup Epsom salt
½ cup hot water
Food colouring (optional)
What to do
Put the Epsom salt and hot water in the cup.
If you want colourful crystals, add two drops of food colouring.
Stir the solution in the cup for five minutes until most of the Epsom salt has dissolved. It is okay if the salt has not entirely dissolved.
Once the salt has dissolved, place the cup into the refrigerator for three hours.
After three hours, you should be able to see crystals at the bottom of your cup. Carefully pour the water into the sink to get a better look at your crystals.
When you are finished, you can dispose of the crystals in the garbage and wash the cup well.
Epsom salts dissolve in hot water. In chemistry terms, our solvent is water and our solute is Epsom salt, also known as magnesium sulfate.
Once you place the cup into the cool environment of the refrigerator, the warm solution inside the cup gets colder. Cold substances have less energy than hot substances, so the salt molecules don’t move around as much and they start to connect. Magnesium sulfate joins together in an ordered pattern, causing crystals to form.
True or false? A lobster’s blood is blue when exposed to oxygen.
Which element makes up majority of air in our atmosphere?
Where are most of Earth’s active volcanoes located?
What is the name of Neptune’s largest moon?
What is the largest muscle in the human body?
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