FACT SNACK

August 7

Be Still My Beating Heart...

How fast is a heartbeat? Depends on the heart. The human heart beats about 70 times per minute, and up to 150 times per minute if a person is frightened or doing a strenuous activity.

All Creatures Great and Small. In all creatures, the size of the heart is proportional to body mass, and usually the smaller the heart, the faster the heartbeat.

Ya Gotta Have Hearts... One of the most primitive vertebrates, the hagfish, has four types of hearts.

Smaller! Faster! Consider the tiny hummingbird, the helicopter of the bird world. A hummingbird's heart can beat up to 1,300 times per minute.

Northern Short-tailed Shrew ~ Blarina brevicauda

That's Funny. You Don't Look Shrewish. The shrew, who is a lot smaller than your average human, has a heart that beats about 600 times a minute.

Bear With Me... A black bear's heart may only beat 40 to 50 times per minute,
A Whale of a Big Heart. The blue whale has a heart about the size of a Volkswagen. It can weigh up to 2,000 pounds, pumps 10 tons of blood through its body, and beats only about 10 times a minute. The aorta of a blue whale's heart is so big a person could crawl through it. The blue whale is the largest mammal in the world, and possibly the largest that ever lived.

Blue Whale Photo Credit: NOAA Photo Library

Link for More.

Blue whale tales.

Online exploration of the human heart.

Care, feeding, and observation of hummingbirds.