Ever wondered which animal’s heart is the largest in the world? The blue whale’s heart. Its heart alone can weigh about 450 kg. It’s said that its blood vessels are wide enough for a baby to crawl through.
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.
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.
Credit : Practically
Picture Credit : Google
