A strange fact regarding heart beats relative to size.

I had once heard that interestedly enough, a mouse compared to an elephant will have the same amount of heart beats in its life.
I was'nt sure if there was any truth to it but did some searching and found this.

The heart of a 1-ounce mouse beats roughly 600 times per minute. The mouse lives an average of three years. An elephant's heart beats just 30 times per minute, but a 5-ton elephant will likely live 60 years or more.

In both cases, if the animals' pulse rate is scaled inversely as the quarter-power of the animal's mass, this notable fact is produced: The total number of heartbeats in a mouse's and an elephant's average life span will be roughly the same, about 946 million times. Used this way, the quarter-power law can be used to estimate life span.

But even odder is the fact that in relation to humans that goes out the window.

But other species, such as people, mess up the equation. A human heart, beating a normal 65 times per minute, hits the 946 million mark somewhere around the 27th year of life, far short of the average human life span.

Why is that?
Do animals, excluding humans, have a "roughly" set amount of heartbeats?
Where as, maybe humans have evolved past this??

Source for link.
www.signonsandiego.com...


[edit on 23-11-2006 by Denied]

I've heard this before, it is an interesting factoid.

I think humans are an exception because of our technology, intelligence, agriculture, and healthcare has greatly extended our lives.

To add.

I wanted to find out, on average how many heartbeats a mammals heart would beat in "its" lifespan.

Every mammal's heart will beat about one billion times in its lifetime.

biology.plosjournals.org.../journal.pbio.0020440

And a humans heart, on average is 2.5 billion times.

In a 70-year lifetime, an average human heart beats more than 2.5 billion times.

www.americanheart.org...

Obviously medical care has vastly improved, so maybe many, many years ago, there was a blueprint to how many beats a mammals heart would beat, including humans.
And for mammals it has stayed the same.

Bumping this.

Any thoughts or logically explanations for this oddity.

I'm not sure it's an sbsolute measurement, because of the way that animals change in environments controlled by humans. For example, the lifespan of the average cat in the 1950's was about 10-11 years. Now it's not unusual to see a cat that's 15 or older (even 22-23), which certainly would blow the "billion heartbeats" theory out of the water.

Same with dogs.

And so on and so forth. It may be a reflection of the average time a creature can survive in the wild, but I don't think it holds up elsewhere.

I used to say this jokingly..about a "fixxed" number of heartbeats.
The reason I say fixxed, is because of this guy

en.wikipedia.org...

He was an inspiration to millions of runners..But dropped dead at a young age after his daily run. Of a Heart attack. the cause was Cholesterol blockage..probably an inherited trait.

Although the health care side affect, which includes pets, obviously has an effect.
My point is, has nature had an obvious hand in this, to say an elephant compared to a mouse, outside of man's environment, will have the same amount of heart beats amazes me, no matter how big or small you are, you have a set amount of beats....

And probably at some point, humans were the same?

[edit on 25-11-2006 by Denied]

Originally posted by spacedoubt
I used to say this jokingly..about a "fixxed" number of heartbeats.
The reason I say fixxed, is because of this guy

en.wikipedia.org...

He was an inspiration to millions of runners..But dropped dead at a young age after his daily run. Of a Heart attack. the cause was Cholesterol blockage..probably an inherited trait.

Funny you should say that, i only watched a programme on him the other day.
He was a fitness fantic, involved with the new running craze, yet dropped dead of it.

i believe our healthcare and diets play a huge part in our life expectancy.

We might have once had a relative heartbeat to animals. Wasn't the average life expectancy of early humans somehwere in the 25-30 range.

Originally posted by djohnsto77
I've heard this before, it is an interesting factoid.

I think humans are an exception because of our technology, intelligence, agriculture, and healthcare has greatly extended our lives.

so, before aspirin, people dropped dead a few days after their 27th birthday? say it ain't so.


edit: to clarify, the average lifespan was of course much lower than today, but native, tribal cultures had their share of old people and they were effectively living in the stone age. wasn't that long ago, was it?

[edit on 29-11-2006 by Long Lance]