A team of researchers in Australia have imaged fossilized soft organs of early jawed vertebrates for the first time, finding that our ancient fish ancestors’ hearts, livers, and stomachs are strikingly similar to ours.
New techniques have shown that people reached the New World far earlier than the long-standing estimate of 13,000 years ago, but scientists still debate exactly when humans arrived on the continent—and how.
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.
A new analysis of fossil footprints suggests that the 2-meter-tall, 4- to 5-meter-long carnivores that left them could run nearly 45 kilometers per hour, bolstering the evidence that at least some dinosaurs were speedy, agile hunters.