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Sw-AMNH-SQUID Stav LIFE MOLLUSKS GIGANTICOne Mystery Scientists use clues to reveal the secretive life of the giant squid B Y P ATRICIA J ANES ast fall, word spread been considered one of the great Why are you, a paleontologist, around the globe at light- unsolved mysteries of science. That’s interested in studying the ning speed: Japanese because no one really knows where giant squid? scientists had snapped or how this elusive animal lives. “All Being a paleontologist, my chief photos of the elusive of our best preserved specimens have focus is on fossils—mainly the fossils giant squid swimming been hauled up accidentally by fisher- of mollusks (see Nuts & Bolts, p. 11). Ldeep in the Pacific Ocean. “Until then, men,” says Landman. When fishermen But if I am to understand the body no one had ever seen the creature in search of deep-sea fish retrieve structure and behavior of an ancient alive,” says Neil Landman, a paleontol- their nets, sometimes they inadver- mollusk, I have to look at modern ogist at the American Museum of tently scoop up the remains of a giant forms—including the giant squid. Natural History (AMNH) in New York. squid too. “As many as 300 giant Although the scientist spends most squids have been hauled up in the last of his time analyzing fossils, or traces 15 years,” he says. of ancient marine organisms, With the proper training, you can Landman studies the giant squid too. gather a surprising number of clues His goal: to unravel some of the ani- from a dead specimen. That’s where mal’s mystery and hopefully apply Landman’s paleontology background that knowledge to his studies of long- comes in. “As I study fossils, I’m con- extinct sea creatures. “I used to say stantly piecing together the puzzle of that it would be a quantum leap in how a certain animal once lived,” he our understanding of the giant squid says. “That training is useful when if anyone were to capture one on you’re looking at animals as remote film. Now they have,” he says. and elusive as the giant squid.” The giant squid, or Architeuthis So what have scientists deduced SQUID SLEUTH: Neil Landman, a dux (ar-keh-TOOTH-us duks), owes about Architeuthis dux? Landman paleontologist its nickname to its jumbo size— speaks with Science World about the at the American Museum of females can measure 18 meters (60 creature and comments on the signifi- Natural History. ILLUSTRATION: TIM GOLDMAN: LANDMAN: PHOTO BY DENIS FINNIN. COPYRIGHT AMERICAN MUSEUM OF NATURAL HISTORY. HISTORY. DENIS FINNIN. COPYRIGHT AMERICAN MUSEUM OF NATURAL TIM GOLDMAN: LANDMAN: PHOTO BY ILLUSTRATION: feet). The colossal creature has long cance of the recent giant squid photos. 8 March 6, 2006 Science World 9 Mollusks are invertebrates, or animals without a backbone, that have a soft, unsegmented body. The three major groups of mollusks are gastropods (such as snails), bivalves (such as clams), and cephalopods (such as squids). Most mollusks are protected by a hard outer Nuts shell. But a squid’s shell is a long, thin structure located within its soft outer body. & Bolts This structure helps to support the animal. Check it Out: The life-or-death struggle between WATCH OUT: two titans of the deep, a giant squid BEHIND THE Each arm and SCENES: AMNH and a sperm whale, is depicted in tentacle of a scientists pre- one of the 14 dioramas in the giant squid has serve a giant American Museum of Natural about 300 prey- squid specimen History’s Milstein Hall of Ocean catching suckers. inside a chemi- Life. The hall is also home to a 94- cal-filled tank. foot-long model of a blue whale. oxygen isotopes (the three different in the water column, living in different The Museum has been researching types of oxygen atoms that have the areas at various life stages. ISTORY (3) ISTORY That’s because older life forms are biggest eyes of any known animal; to search. There are probably thou- and celebrating the natural world same number of protons, or positively for more than 135 years and has also a part of the diversity of life on they can be as big as a soccer ball. sands of giant squids in the oceans, more than 30 million objects in its charged particles, but a different num- What was your biggest ques- Earth. There is no real dividing line but if scientists weren’t searching in extensive research collection. The ber of neutrons, or electrically neutral tion about the giant squid between living and extinct organisms. Why such big eyes? their main habitat, it was unlikely that Museum’s 200 scientists travel particles). By studying the ratio of before the Japanese scientists That’s one of the many questions they would find one alive. around the world on 100 field expe- these isotopes, we were able to tell captured it on film? ditions each year, studying every- What do scientists know—or we don’t know the answer to. The thing from fossilized insects to bio- what the temperature of the ocean I’ve always wondered if the giant think they know—about the giant squid that the Japanese scientists What clues have scientists luminescent fish and the universe. water was when the statolith formed squid just waits for a meal with its giant squid? photographed was hunting prey in used when deciding what over the lifetime of the animal. arms extended, or if it is a predatory Unfortunately, there are many very deep waters—roughly 900 meters depths to search? To learn more, ask your teacher, Then we compared the tempera- monster that hunts down and devours or visit www.amnh.org. more unknowns than knowns. (2,950 feet). There isn’t any light there. There was always this notion to ture information with ocean-depth its prey. The recent photos show the However, we do know that the giant So why would the squid need such look around 1,000 m (3,280 ft). data. For instance, deep water is squid enveloping the bait in a ball-like squid falls within the group of big eyes? There are some theo- WEB Researchers came up with that colder than shallower water that’s mass of tentacles. So for the first mollusks called cephalopods (SEH- ries: For instance, although the depth because people never warmed by sunshine. So we deduced time, the balance is tipping in the fuh-luh-podz). The amazing thing giant squid is believed to live EXTRA see giant squids in shallow that giant squids live at an average direction of it being a voracious, about giant squids and many other well below the area of the Visit waters. Plus, sperm whales depth of about 300 m (984 ft). active predator. That said, it is tricky cephalopods is that their mouths are ocean where light pene- Scholastic’s live at that depth—and to judge an animal that has been interactive site to surrounded by eight arms and two trates, they may use their experience how scien- sperm whales prey upon But the squid that was recently lured by bait, because the animal has tentacles. They use these muscular large eyes to spot ani- tists study the giant squid. giant squids. photographed was in much been placed in an artificial situation. Then, participate in a live tentacles, which are lined with circu- mals that phosphoresce, online interview with an But my colleagues deeper waters. Why is that? lar suckers, to capture food. or chemically produce American Museum of and I wanted to see if Since sperm whales feed on giant Do the latest photos take any Natural History scientist. Scientists also know that their own light. www.scholastic we could infer the giant squids, the scientists followed these of the mystery out of studying cephalopods are the most sophis- .com/squid squid’s habitat depth by large whales. Then, they lowered a the giant squid? ticated of the invertebrates Why did it take studying its statolith (STAH- baited line to attract the squid. There’s Not at all. It actually whets the (animals without a ALIVE! The first photo scientists so long toh-lith). This tiny structure is similar always a bit of bias when you put out appetite, raising more questions of a live giant squid. backbone); they are to spot a giant to an inner ear bone and helps the ani- GET SET: bait because the animals will come to about the animal’s behavior: What is Scientists very intelligent. squid alive? mal maintain its sense of balance. A at AMNH it. Also, my estimates were averaged its life cycle; how long does it live; is Additionally, we One challenge statolith contains a sort of record of prepare a over the animal’s lifetime. That means it the fastest growing animal in the giant squid know that giant was figuring out the surrounding conditions at the time specimen that over the course of its life, the world? The next step will be trying to for study in 9 squids have the at what depths it formed. It does this by locking in H AMERICAN MUSEUM OF NATURAL ALL OTHER PHOTOS: PORTIA ROLLINGS.COPYRIGHT SCIENCE MUSEUM/HO/AP WIDE WORLD; BOTTOM LEFT: NATIONAL giant squid may migrate up and down capture a giant squid on video. the lab. 10 March 6, 2006 Science World 11.
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