Loh Down Script Archives

Browse Loh Down scripts since the show debuted December 5, 2005.

<< Sep 2 Friday, September 3, 2010

Frog Morphs

Dude looks like a lady?!?

This is Sandra Tsing Loh with the Loh Down on Science, and on how male frogs are morphing into Moms.

Tyrone Hayes, from UC Berkeley, studies how chemicals affect amphibians.

Hayes exposed boy tadpoles to the herbicide atrazine - the planet's most common weed killer. He kept them in ponds polluted with the pesticide at LOWER than EPA-permitted levels. Four years later, he gave each frog a physical.

And boy, or girl, did he get a surprise!

Because ten percent of the "male" frogs had lost all manliness. They had less testosterone and sperm, low sex drives, feminine croaks - they'd even sprouted ovaries!

In fact, some of the transformed frogs mated with unexposed males - AND PRODUCED YOUNG! Now THAT'S an extreme makeover.

Even weirder, while Born-Again males can reproduce like other mothers, chromosomally they're still guys. So every tadpole spawned will ALSO be male. Not good for species survival.

So lay off the atrazine, or in place of HER stories frogs will just be HIStory. Get it? History. All right.

 
<< Older   Scripts between Sep 3 and Aug 9            
 
  Sep 3    Frog Morphs
  Sep 2    Skinput
  Sep 1    Equality
  Aug 31    Cultural Explosions
  Aug 30    Microbe Viscosity

  Aug 27    Magnetic Glue
  Aug 26    Man Flu
  Aug 25    Tree Chimneys
  Aug 24    Seeing into Art
  Aug 23    Phonetic Drift

  Aug 20    AquaJelly
  Aug 19    Grooved Golf Balls
  Aug 18    Skull Mystery
  Aug 17    The Birth of Chardonnay
  Aug 16    Infectious Altruism

  Aug 13    Picture of Health
  Aug 12    Scolding Crows
  Aug 11    Hammerhead Heads
  Aug 10    Black Hole Jets
  Aug 9    Particle Flow

20 scripts shown