Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS
A Science Odyssey Title Earth and Life Sciences Activity Title

non-tabled version

For centuries, humans have asked: How was Earth formed? Where did we come from? What makes us human? This search for beginnings has led twentieth-century scientists on an astounding journey. From the arctic tundra to Africa's Olduvai Gorge to the ocean floor, paleontologists, biologists, and geologists find new clues to the origins of our planet, our species, and life itself. In their quest, they ignite a fierce contest between opposing interpretations of the evidence, a struggle that helps drive science.


Program Contents

The earthquake that shattered San Francisco, California, in 1906 opens a century of explosive discoveries and debates in the earth sciences. We see Earth through the eyes of Alfred Wegener, struggling to convince the scientific establishment of 1911 that continents do move, and watch as radiodating techniques increase Earth's estimated age -- sometimes inspiring skepticism if not outrage. Meanwhile, a parallel upheaval rumbles the life sciences, where new evidence of our primate ancestors and the discovery of DNA's structure stir up controversies of their own. Ancient fossils and living cells give up their secrets to change our view of our species and the mechanics of life.

Hour 1 subtitle Hour 2 subtitle

Prologue
San Francisco earthquake, 1906

Introduction
Earth remains mysterious and unpredictable
  • Earth's Origins?
  • New methods and astonishing ideas
  • What do we know about Earth?
  • Competing disciplines,
    conflicting results
  • Alfred Wegener's
    continental drift theory
  • Searching for proof
Genes and Evolution
The "what" and "how" of evolution
  • The view on Darwin
  • Gregor Mendel's work rediscovered
  • T.H. Morgan confirms genes' existence
    SIMULATION:Morgan's fruit fly experiments
Human Origins?
A bone of contention
  • The Taung skull -- a missing link?
  • The Piltdown Man hoax
  • The Scopes trial

Introduction
A journey to the ocean floor

Plate Tectonics
The earth moves!
  • Harry Hess finds deep sea trenches
  • Multiple proofs of continental drift
  • Eruptions mark the continental plates
  • Impact on evolution
Human Lineage
New branches on the family tree
  • Africa as the cradle of humanity
  • Who is our common ancestor?
Life's Origins?
Evidence, clues, and theories
  • Primordial soup
  • Discovering the structure of DNA
  • Using DNA to trace evolution
  • Sparking life from non-living material
    SIMULATION:Spark of life experiment
  • Meteoric theories
Conclusion

Activities Title

The Long View
Seeing and Believing
DNA "Fingerprinting"
In-Depth Investigation: The Dating Game

Appendix: DNA Findgerprinting




Home | Resources for Educators Menu | Educator's Guide Contents | Help

WGBH | PBS Online | Search | Feedback | Shop
© 1998 WGBH