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Why do blood vessels protect dolphins from brain damage?

By Joyce Lee

November 3, 2022


[photo credit:]

Would you believe the fact that the blood vessels of dolphins help to protect the dolphins from brain damage? surprisingly, Due to the unique structure called retia mirabilia, this is possible. retia mirabilia is an uncommon structure among the ocean species; only some mammals that live underwater contain this type of blood vessel. The veins and arteries are located very close to one another, allowing them to either conjugate or separate to adjust the blood pressure, protecting the brain from damage.

Dolphins are certainly speedy swimmers. When they swim, dolphins wag their tail up and down to increase speed. On average, dolphins swim around 5.4 to 6.14 km/h, and when preparing for a vertical jump, they speed up as fast as 40.38 km/h. This acceleration leads to a creation of blood pressure increase in their body, followed by potential brain damage. Humans, or creatures that live on the land, usually ease the pressure through exhaling; Since dolphins are mammals, meaning they are not capable of breathing underwater, researchers started to wonder about the reason dolphins can regulate the high blood pressure that is followed by a speedy acceleration. In addition, regarding the fact Dolphins are very genius underwater mammals, researchers wondered and even had assurance there would be a particular reason. The answer to their wonder was in the structure of retia mirabilia.

The structure of close placement of the vein and arteries of retia mirabilia allows the arteries and veins to combine and vice versa in order to regulate the risen blood pressure that can potentially lead to damage to the brain. The structure itself seems very different from what people usually expect. They are dense and may look like even clumps of just blood. This retia mirabilia can be also found in other underwater mammal such as the whales. Yet, because of the limited resources, researchers claim they did not 100% discover the interesting blood vessels.

Now when we see dolphins jumping out of the ocean, we can imagine their veins and arteries are working hard in order to keep their brains from damage.


Staff, Science. Why Whales Don’t Get Brain Damage When They Swim. 22 Sept. 2022,

Just a Moment... Accessed 16 Oct. 2022.

All About Bottlenose Dolphins - Adaptations | SeaWorld Parks and Entertainment. Accessed 16 Oct. 2022.

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