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The Immortals

   2014    Science
This episode covers the nature of how life may have developed on Earth and the possibility of life on other planets. Tyson begins by explaining how the human development of writing systems enabled the transfer of information through generations, describing how Princess Enheduanna ca. 2280 BCE would be one of the first to sign her name to her works, and how Gilgamesh collected stories, including that of Utnapishtim documenting a great flood comparable to the story of Noah's Ark. Tyson explains how DNA similarly records information to propagate life, and postulates theories of how DNA originated on Earth, including evolution from a shallow tide pool, or from the ejecta of meteor collisions from other planets. In the latter case, Tyson explains how comparing the composition of the Nakhla meteorite in 1911 to results collected by the Viking program demonstrated that material from Mars could transit to Earth, and the ability of some microbes to survive the harsh conditions of space. With the motions of solar systems through the galaxy over billions of years, life could conceivably propagate from planet to planet in the same manner. Tyson then moves on to consider if life on other planets could exist. He explains how Project Diana performed in the 1960s showed that radio waves are able to travel in space, and that all of humanity's broadcast signals continue to radiate into space from our planet. Tyson notes that projects have since looked for similar signals potentially emanating from other solar systems. Tyson then explains that the development and lifespan of extraterrestrial civilizations must be considered for such detection to be realized. He notes that civilizations can be wiped out by cosmic events like supernovae, natural disasters such as the Toba disaster, or even self-destruct through war or other means, making probability estimates difficult. Tyson describes how elliptical galaxies, in which some of the oldest red dwarf stars exist, would offer the best chance of finding established civilizations. Tyson concludes that human intelligence properly applied should allow our species to avoid such disasters and enable us to migrate beyond the Earth before the Sun's eventual transformation into a red giant.
Series: Cosmos: A Spacetime Odyssey

The Imposter

       History
In 1994, a thirteen year old boy disappeared from San Antonio, Texas. Three and a half years later, he is found alive and well thousands of miles away in a village in southern Spain with a story of kidnapping and torture. His family is overjoyed to bring him home. But all is not quite as it seems.
The boy bears many of the same distinguishing marks he always had, but why does he now have a strange accent? Why does he look so different? Any why doesn't the family seem to notice these glaring inconsistencies? It's only when an investigator starts asking questions that this strange tale takes an even stranger turn.

The Incredible Human Journey: Australia

   2009    History
Dr Alice Roberts looks at our ancestors' seemingly impossible journey to Australia. Miraculously preserved footprints and very old human fossils buried in the outback suggest a mystery: that humans reached Australia almost before anywhere else. How could they have travelled so far from Africa, crossing the open sea on the way, and do it thousands of years before they made it to Europe? The evidence trail is faint and difficult to pick up, but Alice takes on the challenge. In India, new discoveries among the debris of a super volcano hint that our species started the journey much earlier than previously thought, while in Malaysia, genetics points to an ancient trail still detectable in the DNA of tribes today. Alice travels deep into the Asian rainforests in search of the first cavemen of Borneo and tests out a Stone Age raft to see whether sea travel would have been possible thousands of years ago, before coming to a powerful conclusion.
Series: The Incredible Human Journey

The Lost Tribes of Humanity

   2017    History
Alice Roberts explores the latest discoveries in the study of human origins, revealing the transformation that has been brought about in this field by genetics. Traditional Palaeoanthropology, based on fossils, is being transformed by advanced genome sequencing techniques. We now know that there were at least four other distinct species of human on the planet at the same time as us - some of them identified from astonishingly well-preserved DNA extracted from 50,000-year-old bones, others hinted at by archaic sections of DNA hidden in our modern genome. What's more, we now know that our ancestors met and interacted with these other humans, in ways that still have ramifications today. Alice uses these revelations to update our picture of the human family tree.

The Persistence of Memory

   1980    Science
The idea of intelligence is explored in the concepts of computers (using bits as their basic units of information), whales (in their songs and their disruptions by human activities), DNA, the human brain (the evolution of the brain stem, frontal lobes, neurons, cerebral hemispheres, and corpus callosum under the Triune Brain Model), and man-made structures for collective intelligence (cities, libraries, books, computers, and satellites). The episode ends with speculation on alien intelligence and the information conveyed on the Voyager Golden Record.
Series: Cosmos

Through the Wormhole Season 6: Are We Here for a Reason

   2015    Science
Evolution tells us that all life exists for only one purpose: to reproduce. But is that all there is? How could such a simple imperative lead us to create great art and civilizations? A new theory suggests that instead of passing on genes, our ultimate purpose is to process and pass on information. We are the universe figuring itself out. Scientists dig deep into DNA, chemistry, technology and engineering to find the meaning of life. One thing is certain: living is easier if you find a reason for living.
Series: Through the Wormhole Season 6