BEAUTIFUL BUT DEADLY
Famous for being some of the world's deadliest animals, blueringed octopuses are usually quite docile and spend most of their time hiding in rubble and shells. There are between 4 and 10 species in the Hapalochlaena genus, living in shallow seas from Australia to Japan. They are all less than a handspan in size, and each has around 60 bright blue rings which flash as a warning when the octopus feels threatened. The rings contain multilayer reflectors, arranged to reflect blue-green light. The flashing is controlled by muscles that pinch in a surrounding layer of black pigmented chromatophore cells that cover the blue iridescence. When the muscles relax the blue iridescence is exposed. The warning flashes come before the octopus deploys its deadly defensive bite. Bacteria living in their salivary glands make tetrodotoxin, TTX, the same toxin that makes pufferfish deadly to eat. Female blue-ringed octopuses cover their eggs in TTX to protect them from getting eaten.
SPECTACULARLY SEE-THROUGH
Denne historien er fra November 2021-utgaven av BBC Focus - Science & Technology.
Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.
Allerede abonnent ? Logg på
Denne historien er fra November 2021-utgaven av BBC Focus - Science & Technology.
Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.
Allerede abonnent? Logg på
CHANGE THE (BODY) CLOCKS
Why the end of British Summer Time can be a wake-up call for our circadian health
ARE OCTOPUSES SENTIENT?
If you've watched the Netflix documentary My Octopus Teacher or been lucky enough to encounter an octopus in the wild, you'll know there's something special about them.
THE MEXICAN MOLE LIZARD
Imagine what would happen if an earthworm, a lizard, a snake and a mole went on a night out, had too much too much tequila and let their guard down.
Do we finally know how the Egyptian Pyramids were built?
A number of breakthrough studies are beginning to paint a picture of how these wonders of the world were built, but much of the story still remains a mystery...
ECLIPSES ON DEMAND
Inside an unassuming building, behind a damp car park in Antwerp, Belgium, scientists are teaching two spacecraft to be dance partners for a performance that will take place in front of the Sun.
How light's 'secret code' reveals the story of the cosmos
The starlight we can see tells us alot about the Universe, but it's the parts we can't see that contain the biggest revelations
An artificial heart inspired by plumbing
Mechanical circulation could revolutionise transplant design and reduce waiting lists
Major Stonehenge discovery deepens mystery around ancient monument
New findings suggest a key six-tonne stone came from over 450 miles north of the circle
THE UNEXPECTED RETURN OF PNEUMATIC TUBES
Once a pioneering technology that revolutionised deliveries, pneumatic tubes had all but disappeared. Now they're back and enjoying a resurgence
LIVING FOSSILS
FOR SOME CREATURES ALIVE TODAY TIME HAS ALMOST STOOD STILL. MEET THE 'LIVING FOSSILS' THAT GIVE US A GLIMPSE INTO LIFE IN THE DISTANT PAST
