Lifesaving insulin used by Fish-Eating Snails as venom

Fish-eating snails have been found to use insulin to drug their prey before snagging them when they’re going into the equivalent of diabetic shock. The snails can’t move quickly – so they obviously need something to equalize their hunting – and this particular thing does the trick. The cone snail stuns and kills the fish they will eventually eat by overdosing them with insulin. A study published in the Proceedings of the National Academy of Sciences found that plummeting blood sugar levels shock the fish, and then ultimately cause their demise.

Once the fish is not moving, the cone snail injects a second round of toxins into the fish – before pulling it into its mouth. That ensures that the fish is paralyzed. At that point, the cone snail uses a “false mouth” to eat its prey. A cone snail specialist at the Smithsonian pointed out that “It looks like the fish is completely narced.” However, this isn’t the only toxin that has this effect, and in actuality, this would appear to be the cone snail’s typical course of action.


The first round of toxins are rarely to kill, and rather they are meant to daze, confuse, and make the prey immobile before actually making them dinner. Cone snails though have actually been known to kill humans as well. And while they have a good number of kills under the belt on humans – the point of the study was to show just how effective they are at hunting, even though they do not necessarily contain the typical means to hunt. Interestingly though, while some have said that the fish who are targeted by the snails look “drunk,” they don’t actually inject anything to their prey. Rather they spew the toxins out into the water around them.

“We already knew that these animals make hundreds of neurotoxins in their venom and compounds that cause tissue degradation and affect cardiovascular function. Now we can add yet another mechanism to this list: the disruption of the prey’s energy metabolism,” said Helena Safavi, of the University of Utah, and co-author of this particular study. The research on the subject proves just how versatile these creatures are in their natural habitat.