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	<title>Nature &#187; cloning</title>
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		<title>The Vanishing Lions: Cloning the King of Beasts</title>
		<link>http://www.pbs.org/wnet/nature/episodes/the-vanishing-lions/cloning-the-king-of-beasts/543/</link>
		<comments>http://www.pbs.org/wnet/nature/episodes/the-vanishing-lions/cloning-the-king-of-beasts/543/#comments</comments>
		<pubDate>Tue, 30 Jun 2009 17:32:35 +0000</pubDate>
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				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[cloning]]></category>
		<category><![CDATA[conservation]]></category>
		<category><![CDATA[endangered species]]></category>
		<category><![CDATA[genetics]]></category>
		<category><![CDATA[lions]]></category>
		<category><![CDATA[technology]]></category>

		<guid isPermaLink="false">http://www.pbs.org/wnet/nature/2008/06/19/cloning-the-king-of-beasts/</guid>
		<description><![CDATA[
Can the King of Beasts be copied? That is the question some conservationists are pondering as lion populations dwindle worldwide. They say cloning -- using advanced biological techniques to create genetic duplicates of existing lions -- could become part of the effort to save the big cats. Other experts, however, are skeptical. Cloning lions would [...]]]></description>
			<content:encoded><![CDATA[<p style="text-align: center"><a href="http://www-tc.pbs.org/wnet/nature/files/2008/06/590_vanlions_cloning.jpg"><img class="alignnone size-medium wp-image-551 aligncenter" title="lions laying in the grass" src="http://www-tc.pbs.org/wnet/nature/files/2008/06/590_vanlions_cloning.jpg" alt="lions laying in the grass" width="590" height="300" /></a></p>
<p>Can the King of Beasts be copied?<strong> </strong>That is the question some conservationists are pondering as lion populations dwindle worldwide. They say cloning &#8212; using advanced biological techniques to create genetic duplicates of existing lions &#8212; could become part of the effort to save the big cats. Other experts, however, are skeptical. Cloning lions would be difficult and expensive, they argue, adding that it won&#8217;t really solve the major problems facing the big cats, such as habitat loss. For the moment, they say, the money would be better spent on more traditional conservation efforts.</p>
<p>It&#8217;s a debate that couldn&#8217;t have even occurred a decade ago. Cloning a mammal was beyond the reach of science until 1996, when researchers managed to create a cloned sheep named Dolly. Since then, scientists have learned how to clone a host of other mammals, including mice, sheep, cows, dogs, and small cats. In 2002, scientists in Texas announced that they had cloned a domestic cat. They named the genetic replicate kitten &#8220;CC,&#8221; for &#8220;carbon copy.&#8221;</p>
<p>The breakthrough got some cat conservationists thinking. Cloning, they realized, could be a way to preserve the gene pool of dwindling cat populations, and perhaps create robust animals that could eventually be returned to the wild. In theory, genes could even be taken from the frozen tissues of dead animals, then reintroduced into populations through cloning. In essence, the dead could &#8220;walk again.&#8221;</p>
<p>In 2003, one conservation center began to follow through on these ideas. In New Orleans, the Audubon Center for Research of Endangered Species succeeded in cloning the first African wildcat, the bigger, wilder cousin of the common domestic cat. Eventually the team produced seven clones. Then, in 2005, the researchers went a step further. Two of the clones were allowed to mate, producing eight kittens. The births confirmed the idea that maybe, someday, cloned animals might be used to repopulate endangered species.</p>
<p>&#8220;We couldn&#8217;t be happier with these births,&#8221; Audubon researcher Betsy Dresser said at the time. &#8220;By improving the cloning process and then encouraging cloned animals to breed and make babies, we can revive the genes of individuals who might not be reproductively viable otherwise, and we can save genes from animals in the wild.&#8221;</p>
<p>Ultimately, she said, similar techniques might be used to reinvigorate populations of endangered small cats, such as Asia&#8217;s fishing cats and India&#8217;s rusty spotted cat, the world&#8217;s smallest feline. &#8220;The goal is to use whatever tools we can to help boost these populations,&#8221; explained Dresser. She cautioned, however, that while cloning could help conservation, &#8220;no single approach is going to solve the incredibly complex problem of disappearing wildlife.&#8221;</p>
<p>That complexity has helped spark controversy in India, where in 2004 scientists announced ambitious plans to clone the highly endangered Asian lion. Fewer than 300 are believed to exist, and the small group of Indian researchers said they wanted to spend $1 million to clone and restore the big cats.</p>
<p>The announcement drew criticism from conservation groups, who said the project raised false hopes. One problem, they noted, is that even if scientists succeeded in cloning the lions, their natural habitat is rapidly being lost to farms and development. &#8220;We spend millions of rupees trying to clone&#8230;lions, but where will we put them?&#8221; Belinda Wright of the Wildlife Protection Society of India asked reporters.</p>
<p>In addition, experts predict that cloning a lion won&#8217;t be easy. The vast majority of cloning experiments end in failure, they say, noting that it took more than 300 tries to create Dolly the sheep. Adding to the challenge is the fact that every mammal species has its own biological quirks when it comes to reproduction. Cloning a dog proved far more difficult than cloning a cat, for instance, because of some details of its reproductive biology.</p>
<p>In India, lion cloning advocates predict those technical problems will be overcome. So far, however, no scientist has succeeded in cloning one of the big cats. For the moment, weighing the potential risks and benefits of making copies of the King of Beasts remains a mostly hypothetical debate.</p>
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		<title>Obsession with Orchids: Flower Power</title>
		<link>http://www.pbs.org/wnet/nature/episodes/obsession-with-orchids/flower-power/1938/</link>
		<comments>http://www.pbs.org/wnet/nature/episodes/obsession-with-orchids/flower-power/1938/#comments</comments>
		<pubDate>Mon, 10 Apr 2000 18:00:49 +0000</pubDate>
		<dc:creator>admin</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[cloning]]></category>
		<category><![CDATA[orchids]]></category>

		<guid isPermaLink="false">http://www.pbs.org/wnet/nature/2008/09/08/flower-power/</guid>
		<description><![CDATA[

From corsages for the high school prom to showy centerpieces for formal dinner tables, colorful orchids are in big demand. As a result, orchid culture has taken off over the last few decades, as growers using new techniques have learned to scale up production, churning out millions of genetically identical plants through a process called [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://www-tc.pbs.org/wnet/nature/files/2008/10/na_img_obsession_flower.jpg"><img class="alignnone size-medium wp-image-4056" title="na_img_obsession_flower" src="http://www-tc.pbs.org/wnet/nature/files/2008/10/na_img_obsession_flower.jpg" alt="" width="610" height="310" /></a></p>
<p>From corsages for the high school prom to showy centerpieces for formal dinner tables, colorful orchids are in big demand. As a result, orchid culture has taken off over the last few decades, as growers using new techniques have learned to scale up production, churning out millions of genetically identical plants through a process called cloning.</p>
<p>As NATURE&#8217;s <em>Obsession with Orchids</em> shows, cloning allows breeders to turn one plant into thousands, by harvesting a few cells from root tips and growing them in carefully prepared petri dishes. As the clump of tissue grows, breeders can divide it into separate plants, dramatically reducing production costs. As a result, orchids that were once a sign of wealth have become available to almost everyone.</p>
<p>One beneficial side effect of the orchid boom is reduced pressure on wild populations from collectors, who once were primary suppliers to plant shops and collectors. That doesn&#8217;t mean overcollecting isn&#8217;t a problem in some cases: wild populations of Vietnam&#8217;s rare lady slipper orchid, for instance, may have recently succumbed to overzealous pickers. But in most cases the major threat to orchids comes from habitat destruction.</p>
<div class="captionRight">
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<td><a href="http://www-tc.pbs.org/wnet/nature/files/2008/10/286_obsession_flower.jpg"><img class="alignnone size-medium wp-image-4057" title="286_obsession_flower" src="http://www-tc.pbs.org/wnet/nature/files/2008/10/286_obsession_flower.jpg" alt="" width="159" height="157" /></a></p>
<p>Many researchers are cloning orchids.</td>
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<p>In the United States, for instance, the western prairie fringed orchid is threatened by the loss of intact prairies and pesticide use. The flower may grow up to four feet tall and have up to two dozen creamy white fringed flowers. Its pollinator, the long-tongued hawk moth, comes by night, attracted by an intoxicating scent. The moth &#8220;is unremarkable in appearance and coloration,&#8221; says Kathy Martin, a botanist with the U.S. Fish and Wildlife Service in Bismarck, ND. &#8220;What&#8217;s unusual about it is its uniquely evolved tongue for harvesting the orchid&#8217;s nectar.&#8221; As the moth hovers with its long tongue extended into the orchid, two specialized pollen-bearing structures brush pollen onto the insect&#8217;s eyes.</p>
<p>But today, only 2 percent of America&#8217;s tallgrass prairie remains, along with less than 40 percent of the original western prairie fringed orchid populations, Martin says. And pesticides drifting from nearby cropland pose a threat to hawkmoths. As a result, the orchid was listed as a threatened species under the Endangered Species Act in 1989 &#8212; making it one of nearly 2,000 endangered orchids worldwide.</p>
<p>Luckily, the growing interest in greenhouse orchids has also translated into greater interest in conservation. In the case of the prairie fringed orchid, conservationists are working to establish hawkmoth &#8220;corridors&#8221; of native prairie between orchid populations. And in isolated orchid preserves tens or even hundreds of miles apart, they are considering pollinating the flowers by hand. In the end, they hope that such human &#8220;flower power&#8221; will pay off with survival.</p>
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