| |
The Skeptics' Guide To The Universe - Podcast 140 - 3/26/2008
|
|
|
|
|
<<< Back to Podcast Archive
|
|
The Skeptics' Guide To The Universe
The Skeptics' Guide to the Universe is produced by SGU Productions, LLC - dedicated to promoting critical thinking, reason, and the public understanding of science through online and other media. The first episode of the SGU podcast went online on May 4th, 2005. It soon became a popular science/skeptical podcast, and remains one of the most popular science podcasts on iTunes.
SGU Podcasting Awards: SGU on XM: You can listen to the SGU on America's Talk XM 166 every Saturday night from 8-9pm Eastern.
|
Podcast
140
-
March 26, 2008
|
|
Interview with Eugenie Scott; News Items: Rebecca's Asteroid, Airborne Lawsuit, Pregnant Man, Hypnotist Robber; Your Questions and E-mails: Robin Migration, More on Soap; Science or Fiction
|
|
|
|
Segment: News Items
|
|
|
Segment: Questions and E-mails
|
|
Follow up on Robins
|
Dr. Novella,
On the most recent edition of the SGU you mentioned seeing your first robins of the spring. You also stated that you had recently learned that they were non migratory and that they just move from their summer lawn/yard habitat to another habitat in winter. This is not accurate. American Robins are highly migratory. A quick look at a field guide range map shows that they vacate the entire northern half of their breeding range in the winter and that they winter in many areas of the south where they do not occur in the summer. I think where the confusion is coming from is that most people in the northeast, midwest, etc., are used to seeing robins arrive in the spring and spend the summer hopping about their lawns, only to disappear every fall. However, as you were told, robins do winter much farther north than many people are aware of as they do in your area. You were correct that these birds spend the winter in heavier cover such as areas that have evergreens, so people do not generally see them. But, these wintering birds are almost certainly not your local breeders; your local breeders migrate south and a much smaller number of northern birds arrive in the fall to spend the winter in your area. This is actually a fairly common pattern among widespread bird species such as robins, Red tailed Hawks, Horned Larks, and Song Sparrows, the local birds leave for the winter and are replaced by members of the same species (though often a different subspecies) arriving from further north. As a last point, the scientific name for the American Robin is Turdus migratorius. I think the meaning is pretty clear even to those who don't speak Latin.
Thanks for a great podcast and blogs. Keep up the good work.
Sincerely,
Aaron Brees
Des Moines, IA
|
|
More on Soap
|
Yes, the basic idea of a surfactant is a hydrophobe head group and and a hydrophilic tale. One end sits in the water and the other end likes the oily side. However, there is a huge number of different surfactants. They come in anionic, cationic, nonionic and amphoteric varieties. Using these surfactants in a formulation can do all sorts of different things.
If you use one type you can really dry out your skin as it will strip away the natural oil and grease on your skin. Another surfactant could be much milder and leave more of the grease. Baby bath soaps use this kind usually.
These things depend on the active ingredient levels but mostly on the formulation used. It is not a case that if somebody came up with something new everybody wouyld copy it. These formulations can be patent protected and often are. We carry over 11 patents, all on surfactant formulations. Most of these do something pretty unique even though the individual ingredients are the same as others are using.
Mark
From the SGU Boards
|
|
Segment: Interview
|
|
|
Segment: Science or Fiction [ Click Here to Show the Answers ]
|
Question #1  Science
|
Falling coconuts kill more people each year than shark attacks.
|
Question #2  Fiction
|
Astronauts in orbit cannot burp.
|
|
Question #3 Science
|
DNA was first discovered and isolated by Swiss biologist Johan Friedrich Miescher in 1869.
|
|
Question #4 Science
|
Sweden boasts a working hotel sculpted entirely from ice, which has to be rebuilt from scratch each winter.
|
|
Segment: Skeptical Quote of the Week
|
|
Skeptical Quote
|
“It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn’t feel like a giant. I felt very, very small.” - Neil Armstrong
|
|
|
|
|
|