Jeff Corwin was huge today for Amphibian Ark. On “Ellen” this afternoon, he showed a Panama Golden Frog — extinct in the wild, but brought to the show courtesy of the St. Louis Zoo — and explained how chytrid fungus is killing off amphibian species.  He encouraged viewers to go to www.amphibianark.org (yes, he spelled out the url!) to learn how to help.  He offered to let Ellen hold the toad, but she said she didn’t want to be responsible for losing “the last frog.” A “golden” moment for the cause.