Diggester (2492316) writes "How Many Heartbeats Does Each Species Get in a Lifetime? An interesting theory claims that a lifespan for every living creature is equivalent to about 1 billion heartbeats (in average). The theory is based on the correlation between metabolic rate (heart rate) and size of the species. Thus, referring to this claim, animals including humans have about 1 billion heartbeats to use up before they expire."
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