A team led by biologist Henk-Jan Hoving at the Monterey Bay Aquarium Research Institute (MBARI) has examined several videos of these vampire squids taken in natural surroundings at MBARI between 1912 and 2012. They have also conducted experiments to study other elements of these squids like sticky filaments and arm suckers, which help understand their diet system, reported Discovery News.
Scientists were puzzled over the vampire squids as they lack feeding tentacles seen in other cephalopods belonging to the molluscan class like octopus or cuttlefish. The latest study has revealed that the squids have long tendrils called filaments that can extend up to 8 times more than their own body size. When they spread out their filaments, marine detritus like dead crustaceans, eggs and larvae stick to filaments.The arm suckers in the squids did not actually have any sucking capacity. Instead, they release mucus, a kind of fluid secretion that the squids use to wrap their food.
"The suckers on the distal parts of the arms release mucus and they probably wrap the collected food in mucus, forming a food bolus, which is transported via fingerlike projections on the inside of the web to the mouth. Then the food bolus is ingested by the beak," Hoving told Discovery News.
This is the first time such a behavior has been noticed in a cephalopod. Experts pointed out that the vampire squids are the first in the molluscan class, which are not predatory carnivores. This type of eating habit has helped the squids live in oxygen-depleted areas, which in turn, facilitated them to adjust themselves to changing conditions while several other species faced mass extinction over the period.
Researchers hope the study will help in understanding the growth and lifespan of the squids.