Why do only some leaves turn red in the fall? Scientists can't agree on an answer
toggle caption Charlie Riedel/AP
This is the time of year when Nicole Hughes gets constantly distracted by the fall foliage as she drives around North Carolina.
"I'm always looking," says Hughes, a biologist at High Point University. "You know, just seeing what's turned colors when, and what hasn't turned."
Part of her brain is endlessly searching for clues about one of the biggest mysteries of autumn leaves: why the leaves of only some trees turn red.
"We still don't really know why some species turn red and others don't," she says.
Sponsor Message
She's made a career out of studying this, even though her interest in red leaves goes back even further. Growing up, she says, "my dad was always talking about his quest for the perfect red leaf."
Every autumn, trees break down the green chlorophyll in their leaves,
Continue Reading on NPR
This preview shows approximately 15% of the article. Read the full story on the publisher's website to support quality journalism.