We’re living in a period where the gap between rich and poor is dramatic, and it’s continuing to widen. But inequality is nothing new. In a new study published in the journal PNAS, researchers compared house size distributions from more than 1,000 sites around the world, covering the last 10,000 years. They found that while inequality is widespread throughout human history, it’s not inevitable, nor is it expressed to the same degree at every place and time.

The India-Asia continental collision and the uplift of the Tibetan Plateau have long been attributed to continuous Cenozoic convergence with two generic assumptions: the ongoing India-Asia collision and the underthrusting of the Indian continent beneath the Tibet hinterland. This study presents a challenge to the two assumptions through an integrative analysis of geological, geophysical and geochemical data, concluding that the two generic assumptions do not stand under close scrutiny and thus are essentially specious in previous studies. The conclusions have great bearing on the formation and evolution of the Himalaya-Tibet tectonic collage.

In a cave overlooking the ocean on the southern coast of South Africa, archaeologists discovered thousands of stone tools, created by ancient humans roughly 20,000 years ago. By examining tiny details in the chipped edges of the blades and stones, archaeologists are able to tell how the tools were made-- which revealed that people were sharing crafting techniques over wide distances.