Radio Show

JOEL:  When deformed frogs in lakes and ponds around the United States caught the attention of the public a decade ago, puzzled scientists speculated that pesticides were responsible, UV radiation, or maybe, infection. Now, CU-Boulder Assistant Professor Pieter Johnson has led a study, published in the Proceedings of the National Academy of Sciences, showing that that modern agriculture methods are playing an unexpected role: high levels of nutrients used in farming and ranching fuel frog deformities, by enhancing snail populations that spread infectious parasites, called “trematodes,”.  Here’s Professor Johnson:

QUOTE:  Our question really was, what is it that drives the abundance of those parasites.  Nutrient pollution, from fertilizers, construction sites and cow grazing can promote those parasites.  

Johnson says that frogs end up with deformed legs after trematodes burrow into the limbs of developing tadpoles.  This makes the adult frogs easier for birds to catch, which benefits the parasite, because life inside a bird is part of the tremadodes’ lifestyle.  These days, frogs are more scarce throughout the world.  Habitat loss, pesticide contamination and global warming some of the reasons why.  But Johnson says that nutrient pollution from fertilizers, feedlots and construction make a difference, too.  He adds that similar high levels of nutrient pollution increase the chance of other diseases, even in humans, such as cholera and some forms of malaria.

[SUSAN  ] 1: Roughly 1 percent of Neanderthals May Have Been Red-Heads. That’s according to scientists who have been studying DNA samples from Neanderthal remains in Spain and Italy.  Neanderthals lived in Europe and Asia 230,000 years ago.  They disappeared from fossil records 20,000 years ago.  But bone analysis indicates that in some of this now extinct branch of humans, the genes that express the pigment “melanin” were suppressed.  Melanin is the pigment that protects us from the damaging effects UV rays.  Melanin is a key to giving skin and hair its darker tones.  In people who have less of it, pale skin and hair colors ranging from dark red to strawberry blonde are more common.  As for why some Neanderthals were redheads, researchers speculate that if some lived in cooler, cloudier parts of Europe and Asia, the need for melanin may be been reduced.  In fact, having less melanin may have helped their survival, since paler skin has an easier time synthesizing Vitamin D from sunshine . . . sunshine that is scarce in many northern climes.  

In modern humans, redheads are most common in cloudy countries, such as Scotland, where nearly 15 percent of the population is red-headed.  World wide today, red heads are rare . . . about as rare as they probably were among Neanderthals . . . between 1 and 4 percent of the population.

As for other species, Holger Rompler, a Harvard scientist who led the study about Neanderthals, reports that they’ve seen similar mutations in the remains of other extinct species.  For instance, there’s a mutation that may mean there were blond wooly mammoths and may explain, why, today, some mice are lighter colored.

Tonight, you can learn more about Governor Ritter’s Energy Policy’s when Regional Representative Mona Newton speaks at the Boulder Café Scientifique.  That event takes place at Boulder’s Redfish Café and Brewpub, starting at 6 PM.  Also this evening, at the Denver Café Scientique, you can learn about the power of “Computational Thinking,” Clayton Lewis, CU professor of Computer Science, will lead the discussion.  He says it’s not about trying to get humans to think like computers.  It’s about using the skills being gained in Computer Science to solve human problems.  That Denver discussion starts at 6:30 tonight at the Wynkoop Brewery.



[MUSIC BUMPER—NOT THE THEME]

[  J   ] 2: [Intro feature 1] The most power-packed energy particles in the Universe are probably Cosmic Rays.  While they seem to be everywhere, even the world’s best astronomers have puzzled over just how they got there, and where they’ve come from.  Now, using a powerful particle accelerator in South America, a team of researchers from 17 countries has determined that cosmic rays are coming from supermassive “black holes.”   Major contributors to this research effort include CU-Boulder scientists.  


For more on the story, up next,  How on Earth’s Shelley Schlender talkes with CU professor Uriel Nauenberg