Soap in Your 

 Vegetables? 



Worried about germs? To calm your fears, 

 modern corporations have added antimi- 

 crobial compounds to many household 

 products, including cosmetics, soaps, and 

 toothpastes. One such compound is tri- 

 clocarban (TCC). About a million pounds 

 of it are manufactured each year in the 

 United States, and at high doses, it's toxic 

 to people. Once used, the compound 

 gets flushed down your plumbing. Where 

 does it go from there? 



To understand the fate of TCC, 

 Jochen Heidler, Amir Sapkota, and Rolf 

 U. Halden, environmental health scien- 

 tists at Johns Hopkins University in Balti- 

 more, monitored the chemical's journey 

 through a large wastewater treatment 

 plant in the eastern U.S. They've got 

 both good news and bad news to tell. 



The good news is that the plant re- 

 moved 97 percent of the TCC from the 

 wastewater it received, and released only 

 3 percent directly into local bodies of 

 water. The bad news is that the TCC re- 

 moved from the water gets 

 trapped in the plant's reservoirs 

 of sludge, where it seems impervi- 

 ous to degradation by bacteria. 

 All told, the chemists detected in 

 the sludge about 76 percent of 

 the TCC that had originally en- 

 tered the plant. That could be 

 problematic: sludge is often recy- 

 cled as fertilizer, and that could 

 lead to the accumulation of TCC 

 in agricultural fields. From there, 

 the antimicrobial might enter the 

 food supply. TCC in the environ- 

 ment might also give rise to anti- 

 biotic-resistant bacteria. 



The same team recently developed a 

 test for environmental traces of TCC, 

 then sampled waters upstream and down- 

 stream of nine wastewater treatment 

 plants across the country. All of the down- 

 stream and more than half of the up- 

 stream bodies of water showed traces of 

 the chemical. But it's still not clear whether 

 the stuff accumulates and eventually 

 reaches harmful levels in nature. {Environ- 

 mental Science & Technology, doi:10. 

 1021/es052245n, 2006; Environmental 

 Research, in press, 2006) — S.R. 



Death Zone 



In a remote tract of the 

 southwest Pacific, thirty 

 miles east of the eastern- 

 most island in the Samoan 

 archipelago, a volcanic 

 seamount rises nearly 

 15,000 feet from the ocean 

 floor, higher than Mt. Shasta 

 in California. At the center 

 of the seamount is a cav- 

 ernous crater, from which, Cutthroat eels 

 in just the past four years, a 

 towering, thousand-foot-high cone of hard- 

 ened lava has emerged. 



The crater floor is a death zone, accord- 

 ing to Hubert Staudigel, a marine geogra- 

 pher at the Scripps Institution of Oceanog- 

 raphy in La Jolla, California, and his col- 

 leagues. Recently they've been visiting the 

 seamount, 3,300 feet below the ocean's sur- 

 face, and have observed numerous car- 

 casses of crustaceans, fish, and squid on the 

 crater floor. The investigators think that 

 strong currents circulating around the 

 seamount wash hapless midwater creatures 

 into the crater's depths; once there, the ani- 



swarm near their deep-sea volcanic abode. 



mals perish because of toxic emissions from 

 hydrothermal vents. 



But one creature's hell can be another's 

 paradise. Bright red sea worms inhabit the 

 crater, feeding on the bacteria that thrive 

 on the rotting remains. Near the cone's 

 summit lives an army of cutthroat eels, 

 Dysommina rugosa, a species previously 

 known only from trawled specimens. The 

 eels gorge on shrimp carried in by the same 

 currents that occasionally wash some of 

 their comrades into the toxic trap below. 

 (PNAS 103:6448-53, 2006) 



—S.R. 



Keas: nosy by nature 



Avian Einsteins 



To test the intelligence of birds, etholo- 

 gists often present them with a piece of 

 food dangling from the end of a string. To 

 get the food, a bird perched on a branch 

 must reach down, grab the uppermost 

 segment of string in its beak, pull the 

 string up, pin it between foot and branch, 

 reach down, grab the next segment, pull 

 that up, and so on. Devilish variations of 

 the test include forcing the birds to choose 

 between two strings, which may be 

 crossed or pulled to one side by wire. For 



the past decade, the champion string- 

 pullers have been ravens. But recently, 

 keas have taken over the lead. 



Keas are inquisitive, olive-green parrots 

 that live in the mountains of New Zealand. 

 (They occasionally strip windshield wipers 

 off cars, seemingly just for the fun of it.) 

 Seven keas reside in captivity at the Konrad 

 Lorenz Institute for Ethology in Vienna. This 

 septet never saw a string in their lives until 

 Dagmar Werdenich and Ludwig Huber of 

 the University of Vienna submitted them to 

 the string-pulling task. Yet the keas figured 

 out the problem in a matter of seconds on 

 their very first try, faster than ravens ever 

 have. Only one fledgling, which was still 

 developing its beak-foot coordination, 

 failed the test. 



In birds, feats of intelligence often occur 

 in species that use tools or cache food, as 

 ravens do. Keas, however, do neither. But 

 they're gregarious, and intelligence seems 

 to be useful to animals that operate within 

 social networks. Known as the "social func- 

 tion of intellect," that hypothesis has so far 

 been applied mainly to primates. Could it 

 also be valid for birds? (Animal Behaviour 

 71:855-63,2006) —S.R. 



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NA'IUHAI HISTORY July/August 2006 



