Examines the impact of racism in the 20th century. By 1900 European colonial expansion had reached deep into the heart of Africa. Under the rule of King Leopold II, the Belgian Congo was turned into a vast rubber plantation. Men, women and children who failed to gather their latex quotas would have their limbs dismembered. The country became the scene of one of the century's greatest racial genocides, as an estimated 10 million Africans perished under colonial rule.

The final episode begins with a description of the extreme cold conditions that characterized the beginning of the Holocene period, and how species like the bison and the wolf adapted to survive in these hostile environments. We will witness the majesty of the woolly mammoth and the fierce cave lion, with a vivid reconstruction of their struggles for survival. We'll see the impact of climate change during this period, from the expansion of the deserts to the transformation of the tropical rainforests of Africa into grasslands, deeply affecting primates and other animals. It highlights how these changes forced primates to adapt to life on the ground, facing new challenges and predators.
A crucial turn occurred with the emergence of humans as dominant predators and their influence on the extinction of large mammals. The documentary describes humanity's transition from hunter-gatherers to farmers, a change that radically altered the landscape and biodiversity of the planet. Finally, it poses a reflection on the current challenges of climate change and the sixth mass extinction, inviting viewers to consider humanity's crucial role in shaping the future of the Earth.

The universe began with a massive expansion, billions and billions of years ago, and it continues to expand with every passing second. The idea that the universe, and man's very existence, began with a "Big Bang" is no longer a topic of debate among most scientists--it is essentially taken as fact.

This episode explores the wave theory of light as studied by mankind, noting that light has played an important role in scientific progress, with such early experiments from over 2000 years ago involving the camera obscura by the Chinese philosopher Mozi. Tyson describes the work of the 11th century Arabic scientist Ibn al-Haytham, considered to be one of the first to postulate on the nature of light and optics leading to the concept of the telescope, as well as one of the first researchers to use the scientific method. Tyson proceeds to discuss the nature of light as discovered by mankind. Work by Isaac Newton using diffraction through prisms demonstrated that light was composed of the visible spectrum, while findings of William Herschel in the 19th century showed that light also consisted of infrared rays. Joseph von Fraunhofer would later come to discover that by magnifying the spectrum of visible light, gaps in the spectrum would be observed. These Fraunhofer lines would later be determined to be caused by the absorption of light by electrons in moving between atomic orbitals when it passed through atoms, with each atom having a characteristic signature due to the quantum nature of these orbitals. This since has led to the core of astronomical spectroscopy, allowing astronomers to make observations about the composition of stars, planets, and other stellar features through the spectral lines, as well as observing the motion and expansion of the universe, and the existence of dark matter.

25 years ago, NASA launched one of the most ambitious experiments in the history of astronomy: the Hubble Space Telescope. In honor of Hubble's landmark anniversary, know the remarkable story of the telescope that forever changed our understanding of the cosmos and our place in it". But amazingly, when the telescope first sent images back to earth, it seemed that the entire project was a massive failure; a one-millimeter engineering blunder had turned the billion-dollar telescope into an object of ridicule. It fell to five heroic astronauts in a daring mission to return Hubble to the cutting edge of science. Hear from the scientists and engineers on the front line who tell the amazing Hubble story as never before. This single telescope has helped astronomers pinpoint the age of the universe, revealed the birthplace of stars and planets, advanced our understanding of dark energy and cosmic expansion, and uncovered black holes lurking at the heart of galaxies. For more than a generation, Hubble's stunning images have brought the beauty of the heavens to millions, revealing a cosmos richer and more wondrous than we ever imagined. Join us for the story of this magnificent machine and its astonishing discoveries.

As tuition rates spiral beyond reach and student loan debt passes $1 trillion (more than credit card debt), IVORY TOWER asks: Is college worth the cost? From the halls of Harvard, to public colleges in financial crisis, to Silicon Valley, filmmaker Andrew Rossi assembles an urgent portrait of a great American institution at the breaking point. Through interviews profiled at Arizona State, Cooper Union, and Sebastian Thrun's Udacity-among several others-IVORY TOWER reveals how colleges in the United States, long regarded as leaders in higher education, came to embrace a business model that often promotes expansion over quality learning. Along the way we also find unique programs, from Stanford to the free desert school Deep Springs to the historically black all women's college Spelman, where the potential for life-changing college experiences endure.