In 2015, the Smithsonian's National Zoo and Conservation Biology Institute keepers, scientists and researchers took to social media to give the public a behind-the-scenes look into the world of saving giant pandas.

Chapter 1: Sperm on a Plane

Let’s talk about panda sex (or perhaps lack thereof). Panda breeding season is a race against the biological clock. It only comes once a year for 24-48 hours, and our giant panda team must be ready. Our female giant panda Mei Xiang should enter estrus before the end of May. The panda team will artificially inseminate her with frozen-thawed semen. This year for the first time, our panda team may use semen collected from a male panda living in China. With only 2,256 pandas on the planet, 392 of which live in human care, genetics play a big role in breeding season. The best genetic match for Mei Xiang happens to be in China. So, what’s a scientist to do when the best genetic match for your female panda is on the other side of the world? Fly frozen semen to the intended female. For the next 24 hours we’ll bring you a behind-the-scenes look at the trip. SBCI scientist Caitlin Burrell is making the trip from the Bifengxia panda base with the cargo. #PandaStory #InstaScience

A post shared by Smithsonian's National Zoo (@smithsonianzoo) on Apr 19, 2015 at 4:15pm PDT

Chapter 2: To the cryopreservation bank!

Let's Talk About (Panda) Sex

Chapter 4: Sperm Meets Egg, (Hopefully)