Spider which uses spring trap to capture prey discovered in Australia
A new species of spider which weaves a catapult-like silk trap to snare a single type of ant has been discovered in the remote rainforests of northern Australia.
Researchers believe the nocturnal predator developed the unique hunting method to make meals of aggressive ants which are notoriously dangerous - and unusual - prey for arachnids.
The snare's "exceptionally high power" flings the ant into a bigger web at "15 times the most extreme g-forces experienced by jet pilots", said lead researcher Prof Ajay Narendra.
Though it is yet to be formally named, scientists have nicknamed the tiny spider "ballista", after the ancient weapon used to hurl stones in battle.
"The snare mechanism seems to have evolved as a highly specialised way of allowing the spider to 'pick off' potentially hazardous prey one at a time and transport them a safe distance away from ant trails and nests," researcher Dr Jonas Wolff said.
Ants have chemical defences, including the ability to sting in some species, and can recruit throngs of other ants rapidly as backup to overcome potential predators, Narendra explained.
Their team, from Australia's Macquarie University, spent 10 nights in the tropical rainforests of northern Queensland, capturing the spider's behaviour using high-speed and infrared cameras.
According to their findings, published in the journal Current Biology, the ballista spider resides on trees occupied by the aggressive and territorial green tree ant Oecophylla smaragdina, spending the day in webs hidden beneath the underside of leaves.
After nightfall, it drops down some 50cm to a leaf, a branch or the forest floor and creates an anchor point using a silk line.
It then spends hours creating a cone-shape "scaffold" of dozens of tension lines, around which it finally wraps a thinner type of silk before retreating upwards.
Within moments, scientists found green ants approached the trap and bit it - causing the snare to spring and the prey to be launched into the spider's web at "extreme" acceleration.
Read the full story at BBC ↗
Researchers from Macquarie University have documented a previously unknown spider species in northern Queensland rainforests that hunts green tree ants using a catapult-like silk mechanism. The spider constructs a tension-based trap by anchoring a silk line, building a cone-shaped scaffold of dozens of tension lines, then wrapping a thinner silk layer around it. When an ant bites the trap, it springs and launches the prey at high acceleration into the spider's main web. Scientists measured this acceleration at approximately 15 times the g-forces experienced by jet pilots. The researchers spent 10 nights in the field using high-speed and infrared cameras to capture the behaviour. The specialised hunting method appears suited to targeting ants that possess chemical defences and can rapidly summon colony reinforcements—making them dangerous prey for most predators. The findings were published in Current Biology.
Read the full story at BBC ↗
A new species of spider which weaves a catapult-like silk trap to snare a single type of ant has been discovered in the remote rainforests of northern Australia.
Researchers believe the nocturnal predator developed the unique hunting method to make meals of aggressive ants which are notoriously dangerous - and unusual - prey for arachnids.
The snare's "exceptionally high power" flings the ant into a bigger web at "15 times the most extreme g-forces experienced by jet pilots", said lead researcher Prof Ajay Narendra.
Though it is yet to be formally named, scientists have nicknamed the tiny spider "ballista", after the ancient weapon used to hurl stones in battle.
"The snare mechanism seems to have evolved as a highly specialised way of allowing the spider to 'pick off' potentially hazardous prey one at a time and transport them a safe distance away from ant trails and nests," researcher Dr Jonas Wolff said.
Ants have chemical defences, including the ability to sting in some species, and can recruit throngs of other ants rapidly as backup to overcome potential predators, Narendra explained.
Their team, from Australia's Macquarie University, spent 10 nights in the tropical rainforests of northern Queensland, capturing the spider's behaviour using high-speed and infrared cameras.
According to their findings, published in the journal Current Biology, the ballista spider resides on trees occupied by the aggressive and territorial green tree ant Oecophylla smaragdina, spending the day in webs hidden beneath the underside of leaves.
After nightfall, it drops down some 50cm to a leaf, a branch or the forest floor and creates an anchor point using a silk line.
It then spends hours creating a cone-shape "scaffold" of dozens of tension lines, around which it finally wraps a thinner type of silk before retreating upwards.
Within moments, scientists found green ants approached the trap and bit it - causing the snare to spring and the prey to be launched into the spider's web at "extreme" acceleration.
Read the full story at BBC ↗
A new spider species has been discovered in remote rainforests of northern Queensland The spider uses a spring-loaded silk trap to capture green tree ants The trap accelerates prey at approximately 15 times the g-forces experienced by jet pilots Researchers believe the nocturnal predator developed this unique hunting method to safely handle unusually dangerous prey for spiders The spider constructs its trap by anchoring a silk line, building a cone-shaped scaffold of tension lines, then wrapping thinner silk around it Green tree ants possess chemical defences and can rapidly recruit colony members as backup The researchers nicknamed the spider 'ballista' after an ancient stone-hurling weapon Macquarie University researchers spent 10 nights documenting the behaviour using high-speed and infrared cameras The findings were published in Current Biology
Read the full story at BBC ↗
- A previously unknown spider species discovered in Queensland rainforests uses a spring-loaded silk trap to capture aggressive green tree ants
- The trap accelerates prey at extreme g-forces (15 times that experienced by jet pilots) to incapacitate hazardous prey
- Researchers from Macquarie University documented the behaviour using high-speed cameras and published findings in Current Biology
- The specialised hunting method appears evolved to safely handle ants that possess chemical defences and can rapidly recruit reinforcements