The secrets of venom
Ngā mea huna a te paitini
Venomous bugs use stings, bites, and injections in attack and defence. They hurt, paralyse, and kill. But how might we use them in medicine?
Dondale's water spider
Dondale’s water spider rests its feet on the water’s surface, feeling for vibrations. When it senses a small fish, it runs across the water and pounces, paralysing its prey with venom.
Then it drags the fish out, injects it with digestive enzymes, and begins its long feast.
New Zealand giant centipede
Secret: Deadly limbs
Venom isn’t always delivered with a sting or bite. Centipedes use a pair of pincer-like limbs to inject their prey with venom.
The New Zealand giant centipede can grow up to 16 centimetres long. How many legs does it have? That depends on its age, but it’s never 100!
Chilean rose tarantula
Secret: Medicinal venom
The Chilean rose tarantula uses its venom to paralyse its prey. But that venom might come in handy for you humans.
In some damaged human hearts, small channels let calcium through, triggering spasms. The tarantula’s venom can block these channels, making it a potential heart medicine.
Secret: Hair attacks
A venomous bite isn’t the only weapon available to the Chilean rose tarantula. It can release hairs from its abdomen too. They have tiny barbs that irritate the skin and cause swelling. Any predator getting a noseful backs off quickly!
Secret: Paralysing parent
The female tarantula hawk has the second-most-painful sting in the insect world. After mating, she uses her venom to paralyse a tarantula – much bigger than her, and deadly to most bugs.
She buries the tarantula with a single egg. When it hatches, the larva uses the tarantula as a living food supply!
Malaysian forest scorpion
Secret: Tail-tip stinger
Scorpions use their stingers to defend themselves and paralyse their prey. The Malaysian forest scorpion can deliver a powerful venomous sting – but for most of its attacks, it prefers to use those large pincers.
Secret: Ultraviolet glow
Scorpions glow blue-green under ultraviolet light. Scientists aren’t sure if they benefit from this, or if it’s just a quirk of nature.
It certainly helps them to be found in the dark with an ultraviolet lamp though!
Secret: Long stinger
The velvet ant isn’t actually an ant – it’s a wasp.
The female’s bright colours warn predators about her sting, which isn’t very toxic but is extremely painful. Her stinger can be half as long as her body!
Secret: Long-lasting venom
Who has the most painful sting in the bug world? Scientists think it’s the bullet ant. Its venom causes shaking, paralysis, and up to 24 hours of pain.
It’s an excellent defence against predators, but the ant rarely uses its venom on prey – it feeds mostly on sugar-rich nectar.
Eastern cicada killer
Secret: Meals on wings
The female eastern cicada killer uses her venom to paralyse cicadas. She doesn’t eat them though. Instead, she airlifts these heavy bugs to her nest.
If she plans to lay a male egg, one cicada is enough to feed the larva – females get up to three.
King baboon spider
Secret: Bark before bite
The king baboon spider’s venom is powerful enough to kill birds and snakes.
When it’s threatened, it rears up and makes a hissing sound by rubbing its first and second legs together. Any creature that ignores the warning could get a nasty bite.
Secret: Stinging bristles
Before the Io moth looks like this, it’s a bright-green caterpillar with bristles all over its body. They release venom at the slightest touch, causing pain and swelling. Not so cute!