What took so long for humans to appear on Earth? The Earth is 4.6 billion years old, and life began about 4 billion years ago, yet humans—the only intelligent, technological species we know of in the ...
Cumulative culture -- the accumulation of technological modifications and improvements over generations -- allowed humans to adapt to a diversity of environments and challenges. But, it is unclear ...
Long before vertebrates walked on land, millipedes had the place to themselves. Hundreds of millions of years before dinosaurs arrived, these early decomposers were helping establish Earth's ...