Few
actions in nature inspire more fear and fascination than snake bites. And the
venomous reptiles have to move fast to sink their fangs into their prey before
their victim flinches, which may be as little as 60 ms when hunting rodents.
Until recently, video technology was not sufficiently sophisticated to capture
the deathly maneuvers in high definition, but recent improvements have made this possible, so
Alistair Evans and Silke Cleuren from Monash University, Australia, decided to
get to the heart of how venomous viper, elapid and colubrid snakes sink their
fangs into their dinner.
Publishing their research in the Journal of Experimental Biology, the
researchers reveal how vipers sink their fangs into their victims before
walking them into position to inject venom. Elapids squeeze venom into their victims by biting
repeatedly. And colubrids sweep their jaws from side to side to tear a gash in
their victim and deliver maximum venom.
But instead of staying in Australia, to
reveal the fine detail of how each family of snakes bites, Cleuren traveled to
the outskirts of Paris, France, home of Venomworld, where Remi Ksas collects
venom from some of the world's most dangerous snakes for medical and
pharmaceutical uses.
There, Cleuren, Anthony Herrel (Museum national d'Histoire naturelle CNRS, France) and Ksas tempted 36 species of snake—from western diamondback rattlesnakes (Crotalus atrox) and west African carpet vipers (Echis ocellatus) to the rough-scaled death adder (Acanthophis rugosus)—to lunge at a cylinder of warm muscle-like medical gel resembling a small animal, recording the encounters with two cameras at 1000 frames/s to recreate the lightning-fast maneuvers in 3D.
Credit: Journal of Experimental Biology (2025).
DOI: 10.1242/jeb.250347
Cleuren recalls that annoying
a venomous snake with a piece of gel attached to a stick was an
incredible adrenaline rush. "I flinched a couple of times," she
admits, but adds that it was worthwhile to get the amazing footage.
After capturing more than 100 snake
strikes in minute detail, the team saw the vipers embed their fangs in the fake
prey within 100ms of launching a smooth strike—with the blunt-nosed viper
(Macrovipera lebetina) accelerating up to 710m/s2 and landing its bite within 22ms; the elapid snakes bit their victims
as quickly as vipers.
In addition, the vipers moved the
fastest as they struck, with Bothrops asper—sometimes known as the ultimate
pit-viper—reaching speeds of over 4.5m/s after hitting accelerations of more
than 370m/s2, although the fastest elapid—the rough-scaled death
adder—only reached speeds of 2.5m/s.
Focusing on the vipers' fangs, the team saw the needle-like teeth sink into the fake prey, but if the viper wasn't happy with the position of a fang, it pulled it out to reinsert it at a better angle, effectively walking the fang forward. Only when the fangs were comfortably in place did the vipers close their jaws and inject venom into their catch.
Credit: Journal of Experimental Biology (2025).
DOI: 10.1242/jeb.250347
In contrast, the elapid snakes,
such as the Cape coral cobra (Aspidelaps lubricus) and the forest cobra (Naja
melanoleuca), used a stealthier strategy, creeping closer to their victim
before lunging and biting repeatedly as their jaw muscles tensed to squeeze the
venom into their dinner.
Meanwhile, the two colubrid snakes,
with fangs further back in their mouths, lunged over the greatest distances
before clamping their jaws around their meal, sweeping their jaws from
side-to-side to tear a crescent-shaped gash in the victim to deliver the
maximum dose of venom. And on one occasion, a blunt-nosed viper misjudged the
distance to its prey, hitting the right fang and breaking it off. But the team
suspects that this occurs more than you'd think, with fangs turning up in snake scats after being swallowed.
Venomous snakes use dramatically
different strategies to deliver their deadly bites. Vipers and elapids strike
elegantly before victims are even aware of their presence and colubrid bites
inflict the maximum damage. These creatures don't pull any punches when they
mean business.
Source: Snakes' biting styles revealed in fine detail for the first time

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