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To: Road Walker who wrote (272681)	2/7/2006 4:11:19 PM
From: Jim McMannis	Respond to of 1575480

Sharks' Sixth Sense Related to Human Genes Ker Than LiveScience Staff Writer LiveScience.com 1 hour, 6 minutes ago The same genes that give sharks their sixth sense and allow them to detect electrical signals are also responsible for the development of head and facial features in humans, a new study suggests. The finding supports the idea that the early sea creatures which eventually evolved into humans could also sense electricity before they emerged onto land. The finding is detailed in the current issue of the journal Evolution & Development. Sixth sense Sharks have a network of special cells that can detect electricity, called electroreceptors, in their heads. They use them for hunting and navigation. This sense is so developed that sharks can find fish hiding under sand by honing in on the weak electrical signals emitted by their twitching muscles. The researchers examined embryos of the lesser spotted catshark. Using molecular tests, they found two independent genetic markers of neural crest cells in the sharks' electroreceptors. Neural crest cells are embryonic cells that pinch off early in development to form a variety of structures. In humans, these cells contribute to the formation of facial bones and teeth, among other things. The finding suggests that neural crest cells migrate from the sharks' brains to various regions of the head, where they develop into electroreceptors. Glenn Northcutt, a neuroscientist at the University of California, San Diego, who was not involved in the study, said the finding was interesting, but that more studies are needed before a direct link between neural crest cells and electroreceptors can be established. "It still requires a definitive experiment, where the developing neural crest cells are marked with dye, the embryo develops and the dye clearly shows up in the electroreceptors," Northcutt said. In the new study, the researchers found snippets of genetic material associated with neural crest cells in the electroreceptors. They did not dye the neural crest cells and trace their development. Our electrical ancestors Scientists think that all primitive animals with backbones, including the early ancestors of humans, could sense electricity. As they evolved, mammals, reptiles, birds and most fish lost the ability. Today, only sharks and a few other marine species, such as sturgeons and lampreys, can sense electricity. "Our fishy ancestors had the anatomy for it," said study team member James Albert, a biologist from the University of Louisiana. The ability to sense electrical signals is useful in aquatic environments because water is so conductive. On land, however, the sense is useless. "Air doesn't conduct electricity as well," Albert said. "When it happens, it's called a lightning bolt and you don't need special receptors to sense it." The development of the electroreceptors is believed to mirror the development of the lateral line, a sense organ in fish that allows them to detect motion in surrounding water. Similar processes are thought also to be involved in the development of the inner ear, the organs which help humans keep their balance. The electroceptors are also believed to behind many sharks' ability to detect changes in the Earth's magnetic field. Other studies indicate that like sailors, sharks can also navigate by celestial cues. Scientists think that these two abilities are what allow some sharks to swim straight lines across vast distances of featureless ocean. One recent study found that a great white shark, nicknamed Nicole, swam nearly 7,000 miles between South Africa and Australia in just under 100 days. Sharks Everywhere: Vote for Your Favorite Great White Shark Sets Ocean-Crossing Record Without Sharks, Food Chain Crumbles The Myth of Tsunami Survivors' Sixth Sense Visit LiveScience.com for more daily news, views and scientific inquiry with an original, provocative point of view. LiveScience reports amazing, real world breakthroughs, made simple and stimulating for people on the go. Check out our collection of Amazing Images, Image Galleries, Interactive Features, Trivia and more. Get cool gadgets at the new LiveScience Store, sign up for our free daily email newsletter and check out our RSS feeds today!

To: Road Walker who wrote (272681)	2/7/2006 4:13:13 PM
From: tejek	Read Replies (2) \| Respond to of 1575480

This is the same butthole who said at the beginning of the war, the war may take six days, six weeks but no more than six months. That was three years ago. What a butthole! Washington digs in for a 'long war' as Rumsfeld issues global call to arms Simon Tisdall Tuesday February 7, 2006 The Guardian The Bush administration's re-characterisation of its "global war on terror" as the "long war" will be seen by critics as an admission that the US has started something it cannot finish. But from the Pentagon's perspective, the change reflects a significant upgrading of the "generational" threat posed by worldwide Islamist militancy which it believes to have been seriously underestimated. The reassessment, contained in the Pentagon's quadrennial defence review presented to Congress yesterday, presages a new US drive to rally international allies for an ongoing conflict unlimited by time and space. That presents a problematic political, financial and military prospect for many European Nato members including Britain, as well as Middle Eastern governments. continued........... guardian.co.uk

To: Road Walker who wrote (272681)	2/8/2006 3:46:08 PM
From: tejek	Read Replies (3) \| Respond to of 1575480

re: This is no time for anyone to be intimidated by bullying tactics. Speaking of which--- Cheney resistant to change in spy program By Steve Holland Vice President Dick Cheney on Tuesday resisted bipartisan appeals for changes in a hotly disputed warrantless eavesdropping program, saying he believed "we have all the legal authority we need." You know what he's saying.....put your money where your mouth is. He's calling everyone's bluff and no one is responding to the dare. Democrats and some Republicans have urged the Bush administration to work with Congress to revise a law already on the books in order to end questions about whether the spy program, initiated after the Sept 11, 2001 attacks, was constitutional. Why urge? They are paper tigers. The presidency is winning and accumulating power in the process.