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The Mastery of Flight

   1998    Nature
The second programme deals with the mechanics of flight. Getting into the air is by far the most exhausting of a bird's activities, and Sir Attenborough observes shearwaters in Japan that have taken to climbing trees to give them a good jumping-off point. The albatross is so large that it can only launch itself after a run-up to create a flow of air over its wings. A combination of aerodynamics and upward air currents (or thermals), together with the act of flapping or gliding is what keeps a bird aloft. Landing requires less energy but a greater degree of skill, particularly for a big bird, such as a swan. Weight is kept to a minimum by having a beak made of keratin instead of bone, a light frame, and a coat of feathers, which is maintained fastidiously. The peregrine falcon holds the record for being fastest in the air, diving at speeds of over 300 km/h. Conversely, the barn owl owes its predatory success to flying slowly, while the kestrel spots its quarry by hovering. However, the true specialists in this regard are the hummingbirds, whose wings beat at the rate of 25 times a second. The habits of migratory birds are explored. After stocking up with food during the brief summer of the north, such species will set off on huge journeys southwards. Some, such as snow geese, travel continuously, using both the stars and the sun for navigation. They are contrasted with hawks and vultures, which glide overland on warm air, and therefore have to stop overnight.
Series: The Life of Birds

The Fukushima Lights

       Technology
Documentary about the Fukushima catastrophe.

The Irrational Health Service

       Medicine
Richard Dawkins examines the growing suspicion the public has for science-based medicine, despite its track record of successes like the germ theory of disease, vaccines, antibiotics and increased lifespan. He notes a fifth of British children are currently not immunised against measles, mumps and rubella, attributing it to fears arising from a highly controversial report linking the vaccine with autism. Dawkins criticizes the growing field of alternative medicine which does not pass the same objective and statistical rigour as scientifically derived treatments using controlled double-blind studies. Without verifiable evidence, alternative therapies must rely on biased anecdotes and word of mouth to perpetuate. Dawkins observes these treatments have fanciful rationales and rituals behind them, with many alternative treatments employing pseudoscientific jargon such as "energy", "vibration" or "quantum theory" to give themselves greater credence to patients.
Series: Enemies of Reason
Everything and Nothing
Everything and Nothing

   2011    Science
A Traveler Guide to the Planets
A Traveler Guide to the Planets

   2010    Science
The Human Body
The Human Body

   1998    Medicine
Wonders Of The Universe
Wonders Of The Universe

   2011    Science
The Sky at Night
The Sky at Night

   2015    Technology
Bible's Buried Secrets
Bible's Buried Secrets

   2011    Culture
The Climate Wars
The Climate Wars

      Nature