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Another team of scientists at the University of California, Santa Barbara grappled with that issue just a few weeks ago and discovered that squid beaks possess various gradations of stiffness, depending on the amount of a certain type of protein. The protein-filled beak tip is quite stiff and hard, with little water around its molecules, while the area around the base contains more water and less protein. It is therefore more flexible. "Here you have a cutting tool that's extremely hard and stiff at its tip and is attached to a material -- the muscular buccal mass -- that has the consistency of Jell-O," said co-author Frank Zok. "You can imagine the problems you'd encounter if you attached a knife blade to a block of Jell-O and tried to use that blade for cutting," he added. "The blade would cut through the Jell-O at least as much as the targeted object. In the case of the squid beak, nature takes care of the problem by changing the beak composition progressively, rather than abruptly, so that its tip can pierce prey without harming the squid in the process. "It's a truly fascinating design!" Plans are already in the works to apply the findings to human hip replacements and other medical applications. Giants Under Human Pressure Although a colossal squid is thought to be able to sever nerve cords of other animals with a single bite, paralyzing them for later consumption, such skills are little match for the overwhelming pressures brought forth by human activities. Even its recent capture proves that people are encroaching more into its habitat. No one knows exactly how many colossal squid exist now, but their suspected main predator, sperm whales, are listed as being "vulnerable" on the latest World Conservation Union's IUCN Red List of Threatened Species. While the New Zealand fishermen who captured the squid were legally approved to fish for Antarctic toothfish in the Ross Sea, the illegal capture and sale of Patagonian toothfish has led to numerous arrests and fines over the years. Toothfish are very slow-growing. Patagonian toothfish, a.k.a. Chilean sea bass, only reach maturity when they are between 10 and 12 years of age, so recovery from overfishing is difficult to near-impossible. Long-line fishery operations also result in by-catch, killing multiple other species, such as seabirds, whales and other types of squid. According to the Monterey Bay Aquarium's Seafood Watch Program, people can do their part by avoiding purchase and consumption of Chilean sea bass. "Scientists estimate that more than half of all the Chilean sea bass sold are caught illegally," said Tim Fitzgerald, an Environmental Defense Fund marine scientist who helps to develop the Seafood Watch list. He added that Environmental Defense has also "issued a health advisory for Chilean sea bass due to high levels of mercury," so avoiding the fish could potentially benefit humans as well as squid.
Jennifer Viegas' blog: Born Animal |
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