David Christian

An introduction to a new way of looking at history, from a perspective that stretches from the beginning of time to the present day, Maps of Time is world history on an unprecedented scale. Beginning with the Big Bang, David Christian views the interaction of the natural world with the more recent arrivals in flora and fauna, including human beings.
Cosmology, geology, archeology, and population and environmental studies—all figure...

In the last millennium, the pace of change accelerated sharply and decisively. Since then, humankind has experienced a number of astonishing changes, including accelerating innovation, the formation of larger and more complex societies, the integration of the four world zones, and the growing human impact on the biosphere.

Although early agrarian societies left behind no written record, there is evidence of many important new developments during this period. Here, we explore the lifeways of these societies, and question whether agriculture meant the early farmers lived better than their forager ancestors.

In this episode, we examine the various kinds of evidence Darwin used to establish his theory of natural selection, including the fossil record, similarities among species, and the geographic distribution of species. We also review modern evidence of natural selection.

After surveying 13 billion years, can we resist peering into the future? We take a tantalizing glimpse into speculations about which historic trends may continue into the next century.

In this episode, we examine the hallmark events of the 20th century, including major worldwide wars, two waves of innovation, huge population growth, and an enormous surge in energy use.

Why should we trust the claims of modern science about events in the distant past? This episode lays some ground rules about evidence for proving scientific claims and describes how new dating techniques have allowed scientists to peer further back into the past than previously thought possible.

In the final episode of this series, we pause to ask some fundamental questions about meaning: What is the place of human beings in the Universe? Are we, perhaps, the only creations of the Universe that have consciousness?

Stars created the preconditions for crossing a third threshold of complexity: the formation of chemical elements. As stars collapse and die, they fuse to create new atoms that are the building blocks of all the complex chemicals that make up our Earth.

To construct the story of hominine evolution, scientists rely on three kinds of evidence: archaeological evidence, evidence based on the study of modern primates, and evidence based on genetic comparisons between modern species of primates, including ourselves.