Skip to main content

biology

Grand forces have shaped American biology across the past sixty-​six million years, from the Paleocene to now.

It was the lead-​up to a presidential election, an unsettling late summer for many Americans since the hugely popular incumbent, Theodore Roosevelt, was declining to run for president a second time.

Enjoy our work? Help us keep going.

Now in its 75th year, American Heritage relies on contributions from readers like you to survive. You can support this magazine of trusted historical writing and the volunteers that sustain it by donating today.

Donate