ナショナルジオグラフィックさんのインスタグラム写真 - (ナショナルジオグラフィックInstagram)「Photo by Cristina Mittermeier @Mitty | A crabeater seal snoozes in the sun in Antarctica. Despite its name, this toothy marine mammal feeds on krill, a small shrimplike crustacean, which is the keystone species of the Antarctic food chain. The krill population in Antarctica has declined 80% since the 1970s, a direct consequence of both climate change and overfishing. In architecture, the keystone is the last piece placed in the construction of a vault or an archway. Placed at the top, it locks all other stones into position and holds them in place, enabling the arch to bear the weight of heavy loads. If you take the keystone away, the archway fails, and the walls they were built to support come crumbling down. Without a healthy and sizable krill population, the Antarctic ecosystem as we know it will fall apart. Follow me @Mitty to learn more about the ways that we can work together in 2020 to establish more marine protected areas in the Antarctic Peninsula. #MPA #CCAMLR #TurningTheTide #ExtinctionEndsHere」12月22日 16時40分