- June 5th is World Environment Day - an annual celebration of our environment meant to encourage people to protect it.
- Human activities like carbon emissions and deforestation are threatening Earth's flora and fauna in unprecedented ways. Many species are resilient - but only to a point.
- These photos, some of them from National Geographic's docu-series "Hostile Planet," reveal the ways Earth's inhabitants are fighting to survive.
- Visit Business Insider's homepage for more stories.
June 5 marks the 35th annual World Environment Day - a global event spearheaded by the United Nations that aims to increase worldwide action to protect our environment.
Every year, the UN campaigns to raise awareness about environmental issues like marine pollution, increasing carbon emissions, and overpopulation. In 2019, the focus is addressing air pollution.
Air pollution causes some 8.8 million deaths annually worldwide. Currently, 91% of the world's population lives in places where the air quality does not meet the standards for safety set by the World Health Organization.
Read More: 19 types of pollution you might encounter every day that could hurt your health
Humans pollute the air, land, and sea by burning fossil fuels, overusing chemicals and pesticides, and creating sewage run-off.
The human health consequences of pollution aside, the degradation of our natural environment is forcing hundreds, if not thousands, of species down a path to extinction.
As news on the environmental front gets more dire - oceans are warming, Arctic and Antarctic ice melt is increasing, 5 trillion pounds of plastic have entered the seas - it's all the more important to remember that our planet is filled with species and habitats worth protecting.
In honor of World Environment Day, we've compiled some of the most beautiful - and heartbreaking - images of our planet and its flora and fauna.
Here are 30 images that illustrate our planet and its species' fragility and resilience.