The ocean is billions of years old. The Pacific Ocean, which is the world’s largest and deepest, is the oldest ocean basin on earth — dating back to about 200 million years ago.

The ocean is home to some of the oldest species on Earth, including frilled sharks (150 million years old), tadpole shrimp (200 millions years old), and sturgeons (200 million years old). Many of these ancient species still look very much the same as they did hundreds of millions of years ago.

The ocean is also home to another very ancient organism called coral. These marine invertebrates live in large colonies known as “coral reefs.”

Coral reefs are among the world’s oldest living things. The world’s largest reef is the Great Barrier Reef in Australia. A crucial part of the ecosystem, it is somewhere between half a million to one million years old. 

How Climate Change Affects the Ocean

While the ocean is indeed ancient and beautiful, it is also in grave danger. Climate change and pollution are making the ocean increasingly hostile to the more than 700,000 species that live in it. According to the United Nations, 90% of large fish populations are disappearing and half of the coral reefs are dead. In 2022, the Australian government reported that over 90% of the Great Barrier Reef was bleached due to warming waters. While bleaching does not kill coral, it puts them under significant stress that could potentially lead to death. It also makes it more difficult for the species that depend on coral to find food.

This shows just how fragile and interconnected our ocean is. When one system is harmed, it causes a domino effect that harms many other systems, which can lead to species becoming endangered or even extinct. A great way to get involved in the fight to save the ocean is to join World Oceans Day.

What is World Oceans Day?

The goal of World Oceans Day is to educate the public about how humans are impacting the ocean, develop an international movement that advocates for our oceans, and to inspire and unite people around the world to take action to save them. The theme of this year’s World Oceans Day is Revitalization: Collective Action for the Ocean. Learn more and get involved here!

Plus, if your students are interested in ocean engineering, introduce them to the field on our Ocean Engineering Career Pathways page!