The physiology of deciduous trees (start time: 11:09) For many people living in places with four distinct seasons, such as here in Colorado, a favorite pastime at this midpoint in autumn is watching the faded leaves fall from their branches, and listening to the crackling sound while raking up the dried leaves. In this week’s How On Earth show, we explore questions like, Why do the leaves of aspen, ash and other deciduous trees “change” color in the fall? (Spoiler alert: They actually reveal their true colors.) Why do they shed their leaves every fall? And what happens to the naked trees in the winter? Host Susan Moran interviews Dr. Stephanie Mayer, a senior instructor emerita in the Department of Ecology and Evolutionary Biology at the University of Colorado Boulder.
-Resources for winter watering:
Colorado State University Extension
Denver Botanic Garden
-Resources for citizen science opportunities:
The National Phenology Network
Host/ Show Producer: Susan Moran
Cohost/Engineer: Joel Parker
Executive Producer: Beth Bennett
Headline Contributors: Lorraine Healy, Max Hebebrand, Shelley Schlender
Listen to the show here:
Podcast: Play in new window | Download (Duration: 25:55 — 59.3MB)
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Baseball Vision (starts at 5:42): The major league baseball season is now in full “swing.” Fans may take it for granted that these professional athletes are in top physical condition. What’s less known is how important it is for baseball players to have perfect eyesight. Batters in particular have some of the best vision in the world. To find out how scientists know this, and study it, and even make it better, How on Earth’s Shelley Schlender last month headed down to spring training in Arizona. There, she caught up with two of the nation’s top experts on the science of vision, and sports.