Sequoia, Mammoth, Rainier, Teton, and Mesa were born on March 30. Denali National Park and Preserve/NPS Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. Four words: sled dog puppy cam. The Puppy Cam at Denali National Park and Preserve in Alaska is back for the season, and viewers can now watch five future canine rangers in action. Named after various national parks, sled dogs Sequoia, Mammoth, Rainier, Teton, and Mesa were born on March 30 . Another pup named Acadia will soon join the team from a partner kennel. Viewers can watch them grow, play, learn, and bond with their human ranger counterparts. Denali’s sled dogs are actual working rangers, carrying on a tradition of helping protect the park’s wilderness that goes back 104 years . They haul supplies and patrol two million acres of land in one of the most wild places in the United States.…