Transcript for National Geographic's most moving pictures of the decade
with some of the most moving images of the decade. Not just of the year here, we are counting down to 2020, of course and national geographic is revealing the top photos but, Adrienne, they are the top photos they are looking out of 20 million to choose from. It's just remarkable. Let me tell you and these were voted on by, of course, fans and viewers of national geographic. These are the best photos and it's still proving a picture is worth a thousand words or more. These are just some of national geographic's best photos of the decade. Mysterious, haunting, Conservation is arguably one of the most important issues of our time. We need to think about how we save the animals, ourselves and the planet. Reporter: Whitney Johnson for national geographic says over the past ten years their photographers have taken more than 21 million pictures like this photo of a hummingbird eating from a microscopic dinner plate. Our photographer, in the case of this project slowed down way down and by doing that he reveals details that we are unable to see otherwise. Last month we set out to pick the best photographs of the decade. But because of advances in technology and because of the power of moving storytelling we had to include this video. Reporter: One of national geographic's most popular Instagram posts ever with nearly 2 million likes is Sudan, the last male of his species, a northern white rhinoceros being comforted by one of his protectors before passing away in 2018 leaving only two females in the world. One reason we chose this photograph, it helps remind viewers and our audience that we have a responsibility to care about animals to care about nature and our relationship with it. Reporter: These pictures taken by motion censored cameras or a camera trap took five months and 200,000 images to capture. Basically you set the stage but you don't know who is going to show up. Reporter: More than a year after camera traps were set up in Los Angeles this elusive mountain lion photographed in front of the iconic Hollywood sign shining a light on our proximity to wildlife. For me these pictures are the ones that delight, the ones that touch our hearts. I hope that these pictures raise awareness for people who really think about how they can make the world a better place.
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