What Darwin Didn't Know: The Modern Science of Evolution Season 1 Episode 5 Geology and Genes: The Geography of Life

What Darwin Didn't Know: The Modern Science of Evolution season 1 episode 5, titled "Geology and Genes: The Geography of Life," explores the role that geography and geology have played in the evolution of life on Earth. Hosted by Dr. Niall Shanks, a philosopher of science, and Dr. Alison P. Galvani, an epidemiologist and evolutionary biologist, the episode looks at how the movement of continents, the formation of mountains, the changing climate, and the migration of animals have all shaped the diversity of life we see today.

The episode begins in the beautiful and diverse Galápagos Islands, where Charles Darwin first developed his theory of evolution by natural selection. Dr. Galvani explains how the isolation and unique geological history of the islands have led to the development of numerous endemic species. She also discusses how the islands' climate has changed over time, leading to the extinction of some species and the evolution of others.

Next, the show looks at the impact of continental drift on the distribution of life on Earth. Dr. Shanks takes viewers on a tour of the Museum of Natural History in New York City, where he explains how the movement of continents over millions of years has led to the separation and divergence of species on different parts of the planet. He also discusses how the history of life on Earth can be traced through the fossils found in different rock layers.

The episode then examines how mountains have influenced the evolution of life. Dr. Galvani travels to the Rocky Mountains in Colorado to talk about how the uplift of the mountains and the changing climate have created a wide variety of habitats, leading to the evolution of diverse plant and animal species. She also discusses how the formation of mountain ranges has acted as a barrier to the spread of some species, leading to the development of unique biotas in different regions.

Finally, the show looks at the role of migration in the evolution of life. Dr. Shanks discusses how the movement of animals and plants around the world has led to the intermingling of different genetic lineages, creating new species and new genetic combinations. He also talks about the impact that human migration has had on the distribution of life, including the spread of invasive species and the loss of biodiversity due to habitat destruction.

Throughout the episode, Dr. Shanks and Dr. Galvani emphasize the interconnectedness of the geology, geography, and biology of Earth. They explain how the history of our planet has led to the incredible diversity of life we see today, and how the continued study of evolution can help us better understand and protect the natural world. "Geology and Genes: The Geography of Life" is a fascinating exploration of one of the most important scientific ideas of our time.