Science News shares a nightmare scenario from the ocean. The lights are low, there’s slow music playing, and look, there’s someone sexy over by the bar who doesn’t seem to want to be drinking alone. You sit together, flirt for a while, things start getting heated, and then the club manager suddenly grows a spike-tipped tentacle that he plunges into both of your skulls, paralyzing you instantly so that he can feed at his leisure:
Conus imperialis venom contains two molecules that mimic bristle worm pheromones and can stimulate mating behaviors, researchers report March 12 in Science Advances. The find raises the possibility that the cone snails are “weaponizing the worms’ own pheromone as a sort of lure,” says Joshua Torres, a medicinal chemist at the University of Copenhagen. “It’s really wild.”
To Torres’ surprise, these small molecules didn’t seem to target neuromuscular pathways and impair their function, like many venom constituents. But the molecules were remarkably similar to some bristle worms’ mating pheromones. Chemically, the snail’s mimics are actually more stable than the worm’s natural pheromones, which degrade relatively quickly after release, Torres says. The match seemed too perfect to be coincidental.
While venom usually does its dirty work via injection, there are some examples of cone snails releasing chemicals into the water column. To test the lure hypothesis, the researchers exposed Platynereis dumerilii worms in petri dishes to the pheromone mimics and watched. When hit with the snail chemicals, 13 of 16 males in the experiment released sperm, and seven of 11 females began swirling around in tight circles — a precursor to mating. While C. imperialis isn’t known to eat this specific worm, the researchers found the DNA of close relatives in the guts of some snails, suggesting that the compounds could be used against more common prey, such as fireworms.
You can read the Science Advances paper here.