SciShow is supported by . Go to to get 20% off of an annual Premium subscription. When it comes to our blood-producing stem cells, biologists have learned that bigger is not better. And a study has taken a look at the accomplishments and obstacles of an in-progress attempt to restore a large belt of degraded land stretching across Africa. Hosted by: Hank Green SciShow is on TikTok! Check us out at @scishow ---------- Support SciShow by becoming a patron on Patreon: ---------- Huge thanks go to the following Patreon supporters for helping us keep SciShow free for everyone forever: Alisa Sherbow, Silas Emrys, Chris Peters, Adam Brainard, Dr. Melvin Sanicas, Melida Williams, Jeremy Mysliwiec, charles george, Tom Mosner, Christopher R Boucher, Alex Hackman, Piya Shedden, GrowingViolet, Nazara, Matt Curls, Ash, Eric Jensen, Jason A Saslow, Kevin Bealer, Sam Lutfi, James Knight, Christoph Schwanke, Bryan Cloer, Jeffrey Mckishen ---------- Looking for SciShow elsewhere on the internet? SciShow Tangents Podcast: Facebook: Twitter: Instagram: ---------- Sources: Images: : : : : :
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