Tue, Mar 31, 2009
Thirteen thousand years ago a great tragedy in North American history caused the extinction of 35 species of large mammals. Scientists are divided on whether the cause was climate change or human predation. Nova follows the investigation of the evidence supporting a third controversial hypothesis; comet impact.
Tue, Oct 20, 2009
This program reviews the monitor lizard genus which, dispute the incredible diversity between species, share common traits such as the ability to count, that lead biologists to peg them as the most evolutionarily advanced of the lizards. Dr. Eric Pianka, who studied lizards for forty years in Australia, serves as guide. Program concludes with the customary, trite comment on human impact on climate change and the environment.