Really Big Hearts

February 11, 2011 at 11:28 am

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By Billie Rubin, Hemoglobin’s Catabolic Cousin, reporting from the labs of Stanford Blood Center

When your heart is all aflutter, who do you resemble most? Romeo & Juliet? Lady Chatterley? Anais Nin and half of Paris? Or possibly a hummingbird if you are really feeling verklempt.

While our heart rate may go up to slightly more than 100 beats per minute when in the presence of our beloved, a hummingbird’s resting heart rate is 615 beats per minute! Their athletic fluttering uses up quite a bit of energy and they need the extra oxygen that their big hearts pump out. Their hearts are about 2.5% of their body weight, whereas ours is just 0.45%. They have the really big hearts of the world with some major blood circulation going on. Imagine blood collection from them… they would need a very, very small needle (butterfly needle, perhaps?) and taking their pulse would be a marathon!

Happy (early) Valentine’s Day ☺