Sharks Have Survived All 5 Global Mass Extinction Events on Earth – But How?

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Sharks could be considered masters of survival given their long history. Spanning roughly 450 million years, they outlive trees, the rings of Saturn, and many other forms of life on Earth.

As a gamer, I’ve often found myself reborn in new worlds after catastrophic events that wiped out countless species. Just like that, Earth has faced five major mass extinction events since the first sharks swam the oceans around half a billion years ago. Each event was a brutal evolutionary filter, erasing life indiscriminately and resetting the ecosystem. But resilient sharks have always managed to survive these cataclysms.

Earth’s five mass extinction events

Major catastrophes, such as mass extinctions, rank among the saddest episodes in Earth’s history. Yet, these disasters also pave the way for dramatic evolutionary transformation, allowing room for novel species to arise and occupy empty ecological spaces.

Approximately 440 million years ago, towards the close of the Ordovician Period, sharks were making their debut in Earth’s oceans, coinciding with the first significant mass extinction event. The primary culprit behind the End-Ordovician extinction was a dramatic increase in global glaciation that triggered extreme climate shifts. As ice retreated, numerous marine species dwelling in shallow waters succumbed to these changes. Additionally, it’s believed that volcanic activity and oceanic oxygen depletion (anoxia) may have contributed to the event. Ultimately, roughly 85% of all species perished during this time.

Approximately 370 million years back, nearly 70% of all species became extinct during the End-Devonian extinction event. The reasons behind it aren’t fully understood yet, but researchers have found indications of volcanic eruptions, oxygen depletion in oceans, and swift global climate fluctuations. This catastrophe led to the disappearance of coral reefs, as well as many jawless fish and various marine creatures.

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252 million years ago, a catastrophic extinction event occurred, known as the “Great Dying” or End-Permian extinction, which wiped out nearly 90% of all species on Earth. Marine lifeforms like trilobites became extinct, while on land, synapsids (ancestors of mammals) were severely affected, but archosaurs (the group that includes reptiles and birds) flourished.

Approximately 201 million years ago, the Earth experienced a major extinction event known as the End-Triassic extinction. This catastrophe paved the way for the era of dinosaurs. The main causes were the splitting of the supercontinent Pangaea, extensive volcanic activities worldwide, and significant global climate shifts. This event marked the beginning of the Jurassic Period, during which around 70-75% of all existing species became extinct. This mass extinction created an opportunity for dinosaurs to dominate the terrestrial landscape.

66 million years ago, I stand awe-struck as a cosmic event unfolds, a space rock approximately 9 miles wide slams into what was once the Americas. This cataclysmic impact cast a shadow over our planet, effectively choking the light of the sun and bringing about an apocalyptic era. Roughly 75% of all species, including the majestic non-avian dinosaurs, were wiped out during this End-Cretaceous extinction. Yet, resilience prevails, as nearly 200 million years after the devastating End-Permian extinction, synapsids found their opportunity to flourish once more. The diversification and spread of mammals, including our own species, marked the beginning of a new chapter in Earth’s history.

Through all of this, sharks maintained their finhold on the world’s oceans.

Why sharks are such incredible evolutionary survivors

Sharks made their appearance on Earth roughly 10 million years prior to the End-Ordovician extinction, around 460 million years ago. At that early stage, sharks lacked teeth and may not have resembled modern sharks significantly. The characteristics we associate with sharks today, such as sharp teeth and streamlined bodies, didn’t fully develop until about 380 million years ago, coinciding with their second mass extinction event, which occurred approximately 10 million years later.

During the Devonian Extinction, a grand opportunity presented itself in the vast oceans, allowing sharks to flourish like never before. It was during this explosive growth period that we witnessed some of the most bizarre shark species ever known, such as the peculiar saw-toothed Helicoprion.

Sharks haven’t thrived due to a solitary factor or hidden advantage; quite the contrary, they’ve endured because of their remarkable diversity. It’s unpredictable where the next extinction risk will emerge, so being prepared for all possibilities has been key. Their unique differences serve as a sort of insurance policy, ensuring that at least some species can navigate even the tightest survival bottlenecks caused by mass extinctions.

Sharks inhabit every ocean globally, from shallow coastal areas to the darkest depths. Some species are aggressive predators, while others feed passively on plankton or seagrass. There’s at least one type that eats only seagrass. Sharks can be specialized eaters, focusing on specific prey, or generalists, consuming whatever they can catch. Remarkably, some shark species can reproduce without a mate. Sharks truly embody survival skills.

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2025-07-23 00:47