Part 4 of the TED Radio Hour episode Repair, Repurpose, Reimagine.

Each year, one cow can belch 220 pounds of the greenhouse gas methane. Animal scientist Ermias Kebreab experimented with alternative cow diets and found a surprising solution: seaweed.

About Ermias Kebreab

Ermias Kebreab is a professor and the associate dean of global engagement at the University of California Davis College of Agricultural and Environmental Sciences. He is also the director of the UC Davis World Food Center.

Kebreab was a contributing author to the Intergovernmental Panel on Climate Change 2019 update on livestock-related emissions and he chaired a Food and Agricultural Organization of the United Nation's task force on feed additives and methane. He has contributed to over 250 scientific articles on the climate impacts of livestock.

Kebreab grew up in Eritrea and earned his bachelor's degree from the University of Asmara. He received his PhD in ecological modeling from the University of Reading. He served as the editor on numerous books on agriculture and animal nutrition.

This segment of the TED Radio Hour was produced by Rommel Wood and Rachel Faulkner and edited by Katie Simon. You can follow us on Twitter @TEDRadioHour and email us at

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