Wearing little more than sneakers, a horde of activists recently dashed through the London Zoo to raise funds and awareness for the endangered Sumatran tiger. The streakers—one for each of the 300 rare cats still remaining in the wild— earned 60,000 pounds (nearly $100,000) for the Zoological Society of London’s work to protect the species. And do you know what a group of tigers is called? A streak! For more information or to see what you can do to help, go to ZSL.org.