The second method of hunting also involves a venom-covered harpoon, but instead, the snail opens its mouth to catch fish and the harpoon is released within the mouth. Only a certain part of the cone does not protect from envenomation. This proboscis can extend to all parts of the shell and handling. Within the proboscis is a tooth or harpoon, coated with species-specific venom. The species that utilize the hook-and-line method use an additional appendage called a proboscis. Within piscivorous snails, two primary methods of hunting have been documented: hook and line versus net hunting. Unsurprisingly, envenomation occurs most often on the palms and fingers. Humans are not typical cone snail prey and envenomation is most likely to occur during handling. The geographic cone is the most toxic of the known species, and several human deaths have resulted from envenomation. Knowing these specific feeding patterns make differentiation of deadly Conus species easier though all cone snails are capable of envenomation. Some feed on worms (vermivores), others on mollusks (molluscivores), and those most toxic to humans feed on fish (piscivores). There is variability in the prey each Conus species tends to hunt. While some species do have eyestalks, the siphon provides a more sensitive method of locating prey, as well as performing additional respiratory functions. These snails sense prey within their environment using an appendage called a siphon. Cone snails range in size from a few centimeters up to 29 cm long. All members of the genus appear similar, but many different Conus species fall under this umbrella, some of which pose a greater threat to humans than others. As the snail continues to grow, it builds upon its patterned shell. The spiral shells of the snail are the life-long habitat for the indwelling predator. The Conus genus, within the Conidae family, is a group of predatory gastropod mollusks. The venom from one cone snail has a hypothesized potential of killing up to 700 people. The handful of humans that are stung by a cone snail is often subject to a venom potent enough to immediately paralyze and eventually kill its prey. While humans are not the intended prey for these mollusks, naive divers may inadvertently pick up cones with the intention of keeping them as souvenirs. One example is the Conus genus, which includes over 500 different species of predatory snails. Consequently, this system may be found in a large subset of diverse marine gastropods beyond just cone snails.Both experienced and novice scuba divers are drawn to warm, tropical seas, but when traveling to these areas, divers must practice additional cautionary measures to avoid predators specific to these environments. To determine if similar mechanisms exist in other members of the Conoidea superfamily, we studied Hastula hectica of the closely related Terebridae family to identify analogous structures critical to the ultrafast prey capture of C. We observed fast venom delivery following such high-speed prey strike, as the velocities of ejected venom dramatically dissipate prior to or during proboscis withdrawal. Subsequently, the radular harpoon reaches high accelerations-achieving velocities that mark this prey strike as the fastest in mollusks and one of the fastest in animals-before even more rapidly decelerating as the bulbous base travels to the end of the proboscis. Energy is stored as the radular harpoon is forced against a unique cellular latch within the proboscis, a distensible appendage, until adequate pressure exceeds the latch mechanism. In this biomechanical study, we studied the priming step, prey strike, and venom delivery of the prey capture. The fish-hunting Conus catus of the family Conidae hydraulically propels a hollow radular harpoon that tethers and injects venom into prey. 4 15:00 - 15:15 The Cone Snail Strikes Back: A Biomechanical Study of an Ultrafast Prey Capture JAN, I* SANGHA, G SCHULZ, JR Occidental College Occidental College Occidental College predatory cone snails have been extensively studied for their venom properties, their ultrafast prey capture mechanism remains relatively recondite.
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