Our pals, the pigments

On the October 21st show, we learned about why leaves change color during the fall in a temperate deciduous forest. Leaves are important sites of photosynthesis during the spring and summer months. The light-absorbing pigment, chlorophyll, gives leaves their green color. Deciduous trees lose their leaves in the winter in part because there is less water available for photosynthesis during the winter because of freezing temperatures. As the leaves senesce, the green pigment cholorphyll is broken down for its nitrogen, thus revealing accessory pigments such as carotenoids (oranges and yellows). Red is also often revealed, although these pigments (i.e. anthocyanins) are thought by some to be produced during the chlorophyll breakdown in order to protect tissues against the harmful rays of the sun - just like sunscreen!  It has also been proposed that red colors may help make plants less susceptible to attack by insects.

As for the news...

• The Ida fossil now thought to be only a distant relative instead of "the link"
• Music benefits exercise
• Vegetarian spider discovered

For the animal sound quiz, we heard from some bird species that spend their winters in the southeast United States, including the Yellow-rumped Warbler, Ruby-crowned Kinglet (pictured right), Yellow-bellied Sapsucker, Dark-eyed Junco, and White-throated Sparrow.

Music featured included The Twilight Sad, Azure Ray, Vivaldi, Olivia Tremor Control, Can, Radiohead, Joan Baez, Talking Heads and more.