This podcast is supported by the Icon School of Medicine at Mount Sinai,

the academic arm of the Mount Sinai health system in New York City,

and one of America's leading research medical schools.

What are scientists and clinicians working on to improve medical care and health for women?

Find out in a special supplement to Science magazine prepared by the Icon School of Medicine

and Mount Sinai in partnership

with science. Visit our website at www.science.org and search for Frontiers of Medical

Research-Women's Health. The Icon School of Medicine at Mount Sinai, we find a way.

Welcome to the Science Podcast for August 11, 2017.

I'm Sarah Crespi.

In this week's show, Lizzie Wade talks with us about the arrival of humans in America.

Could they possibly have come down the coast in boats?

And David Grimm gives us this week's hits from our online news site.

Now we have David Grimm, editor for our daily news site.

He's here to talk about some recent online stories.

Okay, Dave, the first story we're going to talk about is trees doing it for themselves.

The Amazon rainforest gets rained on a lot earlier than one would expect. About two to three months before seasonal winds bring in moisture-heavy air from the ocean,

the rains have been drenching the forest.

Now scientists think they know why.

The trees are making their own rain.

I know.

Oh, gosh.

...