This week’s Cosmos has host Neil deGrasse Tyson playing with dogs and bears, telling us how are eyes are not at their evolutionary peak, taking extinctions personally, and visiting Saturn’s moon Titan.
This week’s excursion into the Cosmos universe deals with evolution. We learn about how dogs domesticated us (not a typo), the quirkiness of DNA, the development of eyes, mass extinctions, and how to compare and contrast Saturn’s moon Titan with Earth. Oh, and Neil deGrasse Tyson is committing to the doofiness of the Starship of the Imagination, so…yeah.
DOGGIES! The episode opens with NdGT fighting off wolves near a campfire by swinging a torch as the beasts approach. That was unexpected. Anyway, this leads into a history of how dogs domesticated humans rather than the other way around. Way back when, during an interlude in the ice age, wolves learned that by making nice-nice with the human folk, they might get some food in return. It was almost presented as a “Gee, this is a nice store you have here mister. It would be a shame if something happened to it,” situation. This led to a conversation about selective breeding based on the most vital abilities of a dog: hunting, gathering, and cuteness.
DNA: The Building Blocks of a Bear’s Fallopian Tubes. The Starship of the Imagination becomes The Magic Schoolbus so we can take a trip through a bear’s circulatory and reproductive system. This is so we can see the inner workings of the creature’s DNA. After NdGT summarizes the plot of Gattaca, we learn about how mutations happen almost randomly, sometimes to a species’ detriment. Other times, these mutations are fortuitous, such as a bear in arctic regions developing white hair. No explanation is offered as to how these mutations occur, but we see that beneficial mutations lead to the evolution of species. Polar bear cuteness is not explicitly discussed, but it is implied.
You can’t spell “Evolutionary Development” with “eye.” NdGT treats us1 to the history of the eye, using a side-by-side comparison of what a camera sees and what a given creature actually sees. Eye evolution has been completely water-based over millions of years since that’s where all life was for the longest time. However, when the transition to land happened, evolution still has not caught up with the transition. Maintaining light and focus in a medium such as air is wildly different than in a liquid medium. Perhaps several hundred million years down the road our eyes will improve and adapt.
Field Trip to the Hall of Extinction. NdGT brings the room down a bit by visiting the imaginary Hall of Extinction, which highlights the five great extinctions known to Earth. First, I would love to visit this museum, so somebody should make it happen. Second, as we tour the Permian wing (about 250 million years ago) we learn that volcanoes in Siberia were the cause of greenhouse suffocation and overheated oceans. NdGT has to sit down a couple of times, making this seem more like an episode of Cosmos: SVU. Stop taking it so personally, dude.
Titan: mAybE. The last trip of the Starship of the Imagination (in the picture above) is to the surface of Saturn’s moon Titan. Unlike any other object in our solar system, Titan has liquids flowing on its surface and a discernible rain cycle. The liquids here are methane and ethane, so don’t get too excited. The cloud cover on the moon is so dense that heat can’t get in, meaning the planet is at a temperature so cold these gases have moved to a different state of matter. Since there is liquid on Titan, there is speculation as to whether life could exist there. Perhaps in four billion years we’ll know the answer.
- Real talk: Eyes gross me out, so this is a loose definition of “treat.” ↵