July 14th was Shark Awareness Day and I want to celebrate these ancient keystone species!
Sharks have existed for millions of years. They are even older than trees. Sharks emerged around 450,000 million years ago, whereas trees emerged approximately 350 million years ago. Human existence pales in comparison to sharks, as modern humans appeared about 300,000 years ago.
Throughout their existence, sharks have played a crucial role in supporting and maintaining the ecosystem in which they live. Sharks are apex predators, which means they prey on sick and weak fish to maintain a healthy overall marine life population. Without them, the food chain and the health of the ocean are thrown off balance.
Sharks also help to mitigate climate change. By consuming dead matter on the ocean floor, sharks play a vital role in maintaining the ocean's carbon cycle. Sharks and other large marine life, such as whales, sequester large amounts of carbon. But when sharks and other large marine life are hunted, this disrupts the ocean’s carbon cycle.
However, despite their importance to the ocean ecosystem and the health of the planet, nearly 77% of shark species are threatened with extinction due to climate change, overfishing, poaching, and habitat loss. According to Marine Megafauna Foundation, each year, approximately 1.5 million tons of sharks are caught by humans and often they are caught in fishing nets meant to catch fish like tuna. If sharks are caught in fishing nets, they usually cannot survive long as they need to swim continously to get oxygen.
According to National Geographic, if the world increased its marine protected areas by just 3%, it could save 99 of the most imperiled shark species, which help to keep the ocean ecosystem in balance.
To take direct action to protect sharks, do not buy or eat products containing shark and avoid eating tuna or only buy sustainably caught tuna, since sharks can often become bycatch of fishing nets.
Learn more about how to help sharks visit Shark Guardian, Save Our Seas, and Shark Stewards.
References:
1. Hoseck, Nicky. 2022, April 21st. “Are Sharks Older than Trees?” Dutch Shark Society. https://www.dutchsharksociety.org/are-sharks-older-than-trees/. www.dutchsharksociety.
2. University of Cambridge. 2025, March 18th. “Genetic study reveals hidden chapter in human evolution.” https://www.cam.ac.uk/research/news/genetic-study-reveals-hidden-chapter-in-human-evolution. www.cam.ac.uk.
3. McKeever, Amy. 2021, July 27th. “The surprising ways sharks keep the ocean healthy.” https://www.nationalgeographic.com/animals/article/surprising-ways-sharks-keep-the-ocean-healthy?loggedin=true. www.nationalgeographic.com
4. Shark Stewards. www.sharkstewards.org
5. Marine Megafauna Foundation. “Human Threats to Sharks and Rays.” https://marinemegafauna.org/human-threats-sharks-rays. www.marinemegafauna.org
6. Gibbens, Sarah. 2019, September 25th. “Less Than 3% of the Ocean is ‘Highly Protected’.” https://www.nationalgeographic.com/environment/article/paper-parks-undermine-marine-protected-areas. www.nationalgeographic.com
