When it comes to protecting the biodiversity of Planet Earth, there is no greater failure than extinction.  Thankfully, only a few dozen species have been officially declared extinct by the US Fish and Wildlife Service in the half century since the passage of the Endangered Species Act.  But, hold on. Aren’t we in the middle of the sixth mass extinction? Shouldn’t the list of extinct species be… way longer?  Well, yeah. Maybe. Producer Taylor Quimby sets out to understand why it’s so difficult to officially declare an animal extinct. Along the way, he compares rare animals to missing socks, finds a way to invoke Lizzo during an investigation of an endangered species of crabgrass, and learns about the disturbing concept of “dark extinctions.”  Featuring Sharon Marino, Arne Mooers, Sean O’Brien, Bill Nichols, and Wes Knapp.   SUPPORT Outside/In is made possible with listener support. Click here to become a sustaining member of Outside/In.  Subscribe to our FREE newsletter. Follow Outside/In on Instagram or Twitter, or join our private discussion group on Facebook   LINKS Check out this 2005 feature from the CBS Sunday Morning archives: In search of the Ivory-billed Woodpecker…  …and this one from 60 minutes, also from 2005, pulled from the archive and rebroadcast after the proposed delisting. Nate’s favorite ivory-billed story came from NPR, and featured songwriter Sufjan Stevens. Watch the US Fish and Wildlife Service virtual public meeting about the proposed delisting of the ivory-billed woodpecker on January 26, 2022. Read this 2016 paper that outlines, among other things, the consequences of being wait-listed under the ESA: “Taxa, petitioning agency, and lawsuits affect time spent awaiting listing under the US Endangered Species Act.” From Simon Fraser University, “Lost or extinct? Study finds the existence of 562 animal species remains uncertain.” More on the unknown status of Cambodia’s national mammal, the kouprey. Wes Knapps’ paper on “Dark Extinctions” among vascular plants in the continental United States and Canada. Read about the extinction of smooth slender crabgrass, the first documented extinction in New Hampshire.   CREDITS Host: Nate Hegyi Reported and produced by: Taylor Quimby Mixer: Taylor Quimby Editing by Rebecca Lavoie and Nate Hegyi, with help from Justine Paradis, Felix Poon, and Jessica Hunt. Rebecca Lavoie is our Executive Producer Special thanks to Noah Greenwald, Jonathan Reichard, Tom Martin, and the Cornell Lab of Ornithology. Music for this episode by Silver Maple and Blue Dot Sessions. Our theme music is by Breakmaster Cylinder. Outside/In is a production of New Hampshire Public Radio Learn more about your ad choices. Visit megaphone.fm/adchoices