'Wonderful net' of blood vessels helps keep whales safe
- Published
Do you know how whales' bodies work to keep them safe in the ocean?
Scientists looking at whales think they have found a special way whales look after their blood pressure.
Blood pressure is the amount of force your heart uses to pump blood around the body.
When whales dive in the sea, they can't breathe to regulate their blood pressure like other animals do.
Scientists discovered that whales use special blood vessels around their brain so they stay safe.
Whales are fantastic divers, and can swim down hundreds of metres!
What does this mean?
Whales are extremely large animals - possibly the biggest ever in the world!
Most large animals - like horses - have pulses through their bodies when they use a lot of energy by moving around.
This is caused by their blood pressure rising and falling as they move.
Horses can regulate these blood pressure pulses by breathing - but because whales don't come up to the surface to breathe very often, they have to do it a different way.
Although they live in the water, whales don't have gills to breathe like fish.
They come up to the surface and take air in through nostrils, which are on the top of their bodies.
This is called a blowhole.
Did you know the longest a whale has been recorded holding its breath is 222 minutes?
Can you see the blowhole?
So how do whales keep themselves safe?
Because whales are so big - if their blood pressure changes too much too quickly they could become very unwell.
When blood pressure quickly changes - when whales move up and down in the sea - it could lead to brain damage from blood moving in and out of the brain.
Luckily, whales have a special system in the blood vessels around their brains, called the retia mirabilia, or wonderful net, which keeps the pressure the same going in and out.
The veins- which carry blood into the heart - and the arteries - which carry blood away - sync up to stop the pressure from changing too much.
Some whales - like the sperm whale - have brains that weigh up to 9 kilograms!
How did scientists find this out?
Because whales are so big - they can be quite difficult to study.
Scientists looked at the blood pressure in 11 different whales, dolphins and porpoises.
They took this information and put it into a special computer, to try and work out if their theory was correct.
Some whales are endangered
However, the scientists say they need to do more research to make sure they're definitely right.
They have to be very careful with their studies - as they don't want to hurt whales in their research.
- Published8 June 2022
- Published28 July 2022
