North America

Diverse lines of evidence point to humans’ presence in the New World long before the dawn of Clovis culture. But rewriting this chapter of human history raises many questions about how these early people came to inhabit these continents.

Researchers excavated human footprints out of a small bluff next to a dried-up playa lake and radiocarbon-dated embedded seeds to around 23,000 years ago. Their results suggest that people entered the Americas thousands of years earlier than the accepted estimate.

In the book’s introduction, “Connections,” Suzanne Simard relates how her “perception of the woods has been turned upside down.”

The crania of individuals who lived in the Yucatán Peninsula during the late Pleistocene show a high degree of anatomical diversity among them, and their skull shapes differ from that of other North American populations of the time.

The animals have a smaller body mass, shorter legs, and longer wings than they did four decades ago.

Population reductions in species such as sparrows and blackbirds reflect a concerning pattern of declining biodiversity across the continent, researchers find.

Populations of the two-foot-long amphibians are declining across North America. Scientists are struggling to find out why, before it’s too late.

Dating back to 16,000 years, items from a dig site in Idaho point to the first settlers arriving by a Pacific coastal route rather than by an ice-free land bridge from Siberia.

Most of the 34 patients are under 10 years old, and almost all have been confirmed as unvaccinated against the virus.

Genetic information from dozens of individuals living 700 to 10,000 years ago reveals connections between Clovis and Native Americans and South Americans.