Watch: Tracking the monarchs to Mexico

April 19, 2019

Before the 1970s, where monarch butterflies overwintered was a mystery. Then researchers succeeded worked with Mexicans to trace the migration to the hills of ...

Border wall could harm endangered animals

February 2, 2017

Biologists are worried that a border wall would cut off dozens of species that migrate between Mexico and the United States. Penn State University biologist Jesse ...
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