In the last 50 years, we have doubled the amount of fish we consume. Globally, billions of people rely on seafood as their primary source of protein. But the oceans can't keep up with so much demand. Around the world, fish stocks have plummeted and fisheries are crashing. People lost out. There was an industry just completely ravaged.
As the global fish supply dwindles, the industry faces a crisis on all sides - including crooked moguls, dubious imports and divisive regulations.

The fourth episode sees host Neil deGrasse Tyson exploring our eternal quest to end hunger and honoring Nikolai Ivanovic Vavilov, pioneer of modern plant breeding, who risked his life for a discovery that would change the history of science. Vavilov's story is marked by both the tenacity and creativity and is particularly tragic. Interwoven into Vavilov's somber narrative are warnings and treatments of science and its ethical implications, especially when science itself comes under attack from political forces.

Episode 7 focuses specifically on first contact and the search for intelligent life in the vastness of the cosmos. Are humans ready to make first contact with other intelligent beings? Is our technology even sophisticated enough to detect communication signals from another world? Who are we to search for alien intelligence when we can't even recognize or respect the consciousness all around us, or even beneath our feet.
Neil deGrasse Tyson reveals the hidden underground network that is a collaboration of four kingdoms of life, and a true first contact story between humans and beings who communicate in a symbolic language and have maintained a representative democracy for many tens of millions of years.

When Homo sapiens, which means 'wise ones,' discovered and controlled fire hundreds of thousands of years ago, everything changed. Fire allowed us to cook food and heat dwellings, and it served as a focal point for storytelling and sharing cultural identity among community members. We don't yet have established parameters for what it means to be 'distinctly human,' It would seem the only thing that separates us from other animals, Neil deGrasse Tyson ponders, is our neurotic need to feel 'special'. Against the backdrop of the Halls of Extinction, Tyson insists that there must be a clear distinction between ourselves and animals that justifies our eating them, wearing them and even bringing an end to their species.
From the birth of the devil in ancient Persia to a searing story of saintliness among macaque monkeys, this episode is an exploration of human potential for change. It concludes with the story of how one of history's greatest monsters was transformed into one of its shining lights.

At 11 o'clock on New Year's Eve of the Cosmic Calendar, Homo erectus stood up for the first time, freeing its hands and earning the species its name. They began to move around, to explore, daring to risk everything to get to unknown places. Our Neanderthal relatives lived much as we did and did many of the things we consider to be 'human.' More restless than their cousins the Neanderthals and Denisovans, our Homo sapiens ancestors crossed seas and unforgiving landscapes, changing the land, ocean and atmosphere, leading to mass extinction. The scientific community gave our age a new name, 'Anthropocene.'
Since the first civilizations we've wondered if there's something about human nature that contains the seeds of our destruction. Syukuro Manabe was born in rural Japan and took an intense interest in Earth's average global temperature. In the 1960's, he would assemble the evidence he needed to predict the increase of Earth's temperature due to greenhouse gases until it becomes an uninhabitable and toxic environment, leading to our extinction. 'This doesn't have to be,' says Neil deGrasse Tyson, 'it's not too late. There's another hallway, another future we can still have; we'll find a way.'

Immense shoals of fish throng our shallow seas. Small fish, in turn, sustain bigger ones. The rich coastal seas are the fishing grounds of our planet and can provide an abundance of food for wildlife and humanity. The seas fringing land make up less than a tenth of the world's oceans but 90 percent of marine creatures live in coastal waters, from fearsome sharks to lowly urchins. Protecting these habitats is a battle humanity must win.