"It's alive!" Since Dr. Frankenstein spoke those famous words, we've been alternately enthralled and terrified by the idea of creating life in the lab. Now, a revolution in genetic engineering and thrilling innovations in synthetic biology are bringing that dream—or nightmare, as the case may be—closer to reality. New tools allow researchers to use cells to create their own DNA and edit it into existing genomes with more ease and less cost than ever before. Along with renewed hopes for treating some genetic diseases, there's serious talk of using the newest technologies to bring long-extinct animals back from the dead – like the team hoping to resurrect the woolly mammoth. Science fiction is quickly becoming science fact. NOVA Wonders explores the benefits and the burden of risk surrounding the controversial new technology
How the passing of time on Earth affects life on a variety of levels, from the daily opening of a flower's petals to the evolution of the horse. A swift journey through the seasons demonstrates how caribou spend most of their time on the move, while the flying squirrel's body clock, attuned to the rhythms of the Earth, is revealed to be the most accurate in nature.