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How fast does the heart of a blue whale beat?

July 07, 2020    7 min read

Can you believe that the biggest animals to have ever lived on Earth are not some prehistoric monsters, but animals that are on the planet even today? The Blue Whale is without a doubt the biggest creature that ever lived on the planet, in terms of size and weight. Even the biggest known dinosaurs were less than half the size of an average blue whale. Once there were over 200,000 blue whales in the oceans, but sadly, there are between 10,000 - 20,000 of these majestic creatures left today. Let’s learn some new things about these colossal underwater mammals.

The blue whale is the true behemoth of the animal kingdom

Blue whales have the distinction of being the largest mammals ever to have existed on Earth. On average, blue whales can grow upto 30 metres (100 feet), and around 4.5 metres (15 feet) in height. Blue whales can weigh as much as 200,000 kilograms. Picture three busses, end to end, and that’s how long a blue whale can be. Just to give you an idea of how big blue whales are, their tongue weighs as much as an elephant, and you can probably accommodate 50 people standing comfortably on it. According to some legends, their blood vessels are so wide that a small person can swim through them!

The biggest babies on the planet

Even at birth, blue whales are a force to be reckoned with. Blue whale calves can measure almost 8 metres in length and can weigh as much as 4,000 kilograms! This makes whale calves bigger than most other full-grown animals. Blue whales also have the fastest growth rate in the animal kingdom, and in the first few months, they can grow by almost 100 kgs every day.

A mighty heart for a mighty creature

To power their humongous bodies, blue whales are equipped with a huge heart as well. The whale’s heart is about 5 feet in length, 4 feet in width and 5 feet in height, and can weigh as much as 175 kilograms, which is the same as some cars. A blue whale's heartbeat is so loud that it can be heard from almost 2 miles away. But that’s not the only interesting thing about a blue whale’s heartbeat. On average, when it is at the surface of the water, the blue whale's heartbeat is around 25 - 35 beats per minute. However, when it dives deep underwater for food, a blue whale’s heartbeat can drop to almost 4 - 8 beats per minute, and sometimes even 2 beats a minute. This effectively allows the blue whale to minimise the amount of work its heart does while continuing to distribute blood evenly around the body, even at extreme depths and cold underwater temperatures.

Whales sleep with their brains awake

Despite being comfortable underwater for upto 30 minutes, whales are mammals, like humans, and must come up to the surface regularly to breathe. Humans however, are involuntary breathers, which means that they don’t need to make a decision whether to breather or not. Breathing is an automatic process for humans and most other mammals. Whales,on the other hand, are conscious breathers, and have to take an active decision, when to breathe. As a result, they never fall asleep completely. Even when they are sleeping, one half of the brain remains awake, to ensure that they don’t drown, while the other half stays awake and alert.

Blue whales have a hidden talent

In addition to being the largest animals on the planet, the blue whales are also the loudest. Whales communicate with each other by 'singing' to each other in super-loud vocal notes, which have been measured as loud as 188 decibels. This is higher than the roar of a jet engine. In fact, the ‘songs’ of the blue whales can travel over 1500 kilometres and can be heard by other whales. Talk about free long-distance calling!

If you liked these fun facts about blue whales, challenge your friends to a trivia contest! Keep visiting www.practically.com for more interesting trivia and fun facts.

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