30/09/2014 09:20 BST | Updated 29/11/2014 05:59 GMT

Five Heart Facts for World Heart Day

It's World Heart Day, so let's delve in to the animal kingdom and feast upon it's many wonderful varieties! From the hugely big, to the impossibly small, the fastest beating and the hardest working, animal hearts are amazingly varied. Check out these great animal heart facts!

How small?!

The smallest heart in the animal kingdom belongs to an insect. Insect hearts are narrow tubes located along their backs that pump blood towards their heads. The Alpatus Magnimius is a type of fruit fly and wins the award for the smallest heart, measuring a truly tiny 0.21mm!

Three is a magic number

Octopi are amazing creatures. As well as being known for their intelligence, clever camouflage, ink sprays and immensely complex eyes, octopi have three hearts. Yes, three! Two of their hearts supply blood to the gills for oxygenation, and the remaining heart pumps blood to crucial organs. What a great system!


Image courtesy of Feans

Long way up

Giraffe's have one of the most obvious and interesting adaptations in the animal kingdom: their long necks. To supply their neck muscles and brain with enough oxygenated blood, a giraffe's blood pressure is the highest of any mammal - a whopping 280/180mm mercury. They also have a clever valve system running the length of their neck to ensure blood reaches their head as efficiently as possible.


Image courtesy of Vaughan Leiberum

What the flap?

If you've ever sprinted when racing a friend on a beach for example, you will have experienced a big increase in your heart rate to possibly as high as 200 beats per minute. Now try to imagine your heart beating at 200 beats per SECOND... This is the kind of heart rate certain species of hummingbird experience when flying at top speed, darting between nest and nectar. Incredible!


Image courtesy of Curt Hart

How big?!

It may not come as much of a surprise to you that the biggest heart belongs to the biggest creature ever to inhabit the earth. Among myriad other facts and records the blue whale lays claim to, it also has the biggest heart of any living thing. The ventricles and atria could be crawled through by a person, as the heart is roughly the same size as a car and weighs well over a tonne.


Image courtesy of Kenny Ross 14

But wait

Surprisingly the final entry in our list is a humble friend and companion, for the animal with the largest heart by body mass of any mammal is in fact, a dog. Woof a surprise!


Image courtesy of Kitenutuk

So there we have it, your heart facts for the day on world heart day. Remember to look after the health of you heart!

Check out Frontier's blog 'Into the Wild' where you can read more articles like this! Happy reading!

- By Jack Plumb